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Post by Bullshop on Apr 12, 2023 9:10:14 GMT -7
Gary what I would do with that load for the 300gn bullet data is first determine the percentage of difference between the starting load and the maximum load given for the 300 grain bullet, then drop the load that same percentage from the starting load given for the 300 grain to use as a starting load for the 330 grain bullet. I would feel pretty good with that. Unless due to bullet shape the heavier bullet is seated much deeper in the case thus reducing the internal volume pressures should be very close to the same. As for me shooting the Quigley this year it is indefinite. Day dreaming of it helped me get through our lingering winter weather but now that its letting up I may be seeing things differently, (lots of work to get done ) I will however Lord willing hold onto the dream by continuing to work out all the sight settings with the 38-55 that would be pertinent to the match. In other words I want to be ready to go even if I don't go. Chance favors a prepared mind !
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Post by missionary on Apr 13, 2023 5:15:37 GMT -7
God does bless our labors ! Looks to me like once we get moved I will "need" to look into a couple 8# jugs of LT-30.
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Post by Bullshop on May 9, 2023 8:46:53 GMT -7
In working on a fairly large order for 45=90 BP ammo I think I have found yet another good use for LT-30 powder. This customer like so many other BP shooters requested Swiss powder but I told him the charge for Swiss would be twice what it would be for the GOEX I use. He was concerned about fouling. I told him that using GOEX with a duplex smokeless load would burn cleaner than any load using straight black powder. He decided to go with my suggestion. The load I worked up with my rifle and his requested bullet the Lyman Postell worked out to be by actual weight 67 grain of FFG on about 10% (6.5gn) of the LT-30. I decided to try the LT-30 as the priming charge because again its burn rate puts it right in the perfect area for the purpose. Using a smokeless powder priming charge in duplexing with black powder the smokeless powder burn rate is critical for a couple reasons. One being it purpose for a clean burn of the BP and the other is to not unduly affect the chamber pressure to push velocity and pressure beyond what is normal for straight BP loads. If the priming charge is too fast burning it raises the pressure as well as being less effective in producing a clean burn for the full length of the barrel. Too fast a burn of the priming charge usually has the chamber end of the barrel pretty clean while the muzzle end can look like normal straight BP fouling. Too slow a burn for the priming charge can have the opposite effect not so much affecting pressure but the barrel condition is reversed where the chamber end can be more fouled than the muzzle end. The burn rate of LT-30 seems just about right for this especially regarding the fact that its volume in this application exactly coincides with the recommended volume of 10% of the main BP charge. I only fired a few shots with my rifle and considering the fact that my rifles 1/20" twist is a wee bit too slow for the length of the Lyman Postell bullet that really needs not slower than an 18" twist to be fully stable but none the less at 100 yards all bullets clustered to about the average for my rifle.
Lord willing another application I hope to try soon with LT-30 will be in Schuetzen application. Apparently I have been awarded stewardship of a Stevens model 44 1/2 in 32-40. I will be prepping for breach seating bullets in this rifle and intend to start out with LT-30 powder because once again its assigned position on the burn rate chart puts it right in the bracket of the traditional suggested powders normally used for this purpose. Am very much looking forward to this next testing.
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Post by Bullshop on May 9, 2023 15:05:25 GMT -7
One more thing I want to mention after todays very small limited simple test with LT-30 powder. First lets back up a little to what I mentioned earlier about the also small simple test with LT-30 as a priming charge in a BP load for the 45-90. Right behind that order I had a small bullet order for the Lyman Snover 45 cal 480gn bullet which is a gas check design whit what has been come to be called the Money nose shape which is kind of an improved Postell shape with more and longer taper. It is the design that seems to be dominating long range BPC for those using grease groove bullets. Since this one from Lyman also has the gas check type base it also gave opportunity to test another of my theories in that I believe this type of bullet base has greater potential for accuracy when used without the gas check and held to normal BP velocity of about 1300 fps + or -. So with that in mind and since I already had the 45-90 out to test the other order and it would need to be cleaned anyway I lubed up the over run of 16 bullets from the order without gas checks. This gave me another chance to test the LT-30 powder as a replacement for 5744 as well as a chance to also test as simple as that may be my theory about the gas check base. Going to the Accurate powders #2 manual they show a starting load of 29.3 for 1243 fps and a max load of 32.5gn for 1413 fps at 27,200 psi of 5744 with a 500gn lead bullet. I chose to go with a 30gn charge. No chronograph today so no good idea of velocity. Accuracy was excellent for the eight shots I fired at 100 yards. My rifle I believe to be a rebuild on an original action has a sort of a built in early pressure warning system. I believe it an original action because it has the original type large diameter firing pin. This large size pin and hole allows primers to flow back into the pin hole in the breach block at the very inset of higher than normal BP pressures. The rearward flow of the primer cup metal from elevated pressures is quickly noticed when opening the breach because that small amount of metal gets sheared off by the lowering of the breach block. In this test there was no primer cup flow indicating normal BP pressure range. Though I do not feel it is needed for ignition uniformity in this case because the bullet and powder charge occupy the greater percentage of case volume I did still use a packing popcorn filler simply because it also acts as a buffer between the exploding powder charge and the soft bullet base cushioning the bullet base from being damaged by the still unburned powder as it is propelled against the bullet base. If like me your a bullet hound and always look for your fired bullets for inspection you will know what I mean as you have already seen the pock marked bullet bases from this. That little bit of PP helps prevent it. A card wad will do the same thing but with a card wad and less than a full case of powder there is the possibility of ringing a chamber if the card wad is a loose fit and falls to the powder depth leaving a space between itself and the bullet base. That is always a no no which filling the case with PP completely eliminates the possibility of. Keep watching for the 32-40 test it should be fun !
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Post by missionary on May 10, 2023 5:42:07 GMT -7
Good Morning Dan Good to read these next issues in the LT-30 quest. Looks like this summer I will restock with LT-30. We have a Navy Arms Roller we rebareled with a Bauska 32".458 years back. Only had a 45-70 reamer but a .458 throat tool added the distance to load the 500 RN out to give us 83 grain room. Worked great with Goex 3F. I know where a 45-90 reamer is sleeping so may put it to work wen we get AZ settled. Work safe up there. Try to resist carrying 2 bags bags of cement around.
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Post by Bullshop on May 10, 2023 7:27:48 GMT -7
G'Day Brother Mike ! No worries mate no cement. Sounds like your roller is something like the 458 RCBS. I remember Ken Waters years ago did an article about the 458 RCBS which is what he called it. It was an in-between case length of the already established rimed 45 straight cases. I remember he used a Navy Arms probably made by Pedersoli rolling block and he several times commented on the tremendous strength of that action. He was only dealing with smokeless loads that would pretty much equal the 458 WM. It was pretty interesting then and now on how when built right a buffalo rifle from the 1870's of the type used to exterminate the subsistence source of native Americans could equal in power the best our industry could come up with for efficient taking of Africa's pachyderms. The only real difference was the fuel used dictated by the era.
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Post by Bullshop on May 20, 2023 9:30:57 GMT -7
So I finally got the 32-40 Stevens and it is a very nice rifle in very good condition and most importantly has a very good bore. Not a perfect bore but very good shootable bore. I was kind of excited to try some LT-30 in it so got to that right away. The bullets I tried were from a Saeco mold for a 200 grain tapered design for breach seating. I cast these very soft at about BHN-8. I was loading these in fixed ammo but with very little of the bullet in the case maybe about 1/4 of the bullet in the case. I ran into a catch 22 situation with the very soft alloy and LT-30 powder in that at about the point where I was getting a good clean uniform burn of the powder the very soft alloy was beginning to fail. I was getting 3 to 4 shots grouping very tightly then the next shots would be totally wild due to leading in the barrel. This repeated several times before I decided that the bullets were too soft for the powder. I really believe that by raising the hardness by a couple Brinell points the LT-30 powder may really shine for accuracy and is something I hope to try. For anyone shooting jacketed bullets it should be very good but that is not something I will ever try in this old classic rifle. Since that experience I have cast some bullets from another Saeco mold for the same tapered design but this one at 170 grain. I cast these in what should be closer to a BHN-10 alloy but I think I will not try these with the LT-30 powder. The reason is that the burn rate seems closer to optimum for the heavier bullets and that working up to the same pressure that showed good grouping with the softer alloy at the same pressure will propell the lighter bullets to an even higher velocity so again may begin to fail because even though slightly harder the lighter bullet has less bearing surface so not quite the grip to the rifling of the longer bullet. I think if tested enough with LT-30 in the 32-40 what I will find is that it will be a very good choice for fixed ammo with hard bullets and full power loads but as has shown not a good choice for the low pressure low velocity Schuetzen type loads. Fortunately IMR 4227 probably the most recommended powder since the introduction of smokeless powder for the 32-40 came to my rescue at 12 grain with the 200 gn Saeco soft bullets and very satisfying groups
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Post by Bullshop on May 31, 2023 7:00:10 GMT -7
Adding another very positive application for LT-30 powder. In my attempt to defy the opinion of the experts that the 40-90 BN Sharps was not an accurate cartridge I decided to try it with LT-30. My rifle has a 1/18" rifling twist so again according to those same people should be limited to a max bullet length of 1.25" for full bullet stability and long range accuracy. While digging through some old stuff I found some paper patched bullets that were cast in a Tom Ballard mold adjusted to drop a bullet length of 1.291" which according to the science of ballistics should not be completely spinning on its center axis fired from my 1.18" twist barrel so should have a slight wobble instead of spinning point on. That may be true and if so may show up at longer ranges in increased drop and drift of a slightly shorter bullet that is spinning perfectly true. I dont know for sure yet because I have only shot it at 100 yards but from that limited testing I can say for sure that the PP bullet at 1.291" length with a charge of 22.5 gn of LT-30 has turned in the best groups I have ever fired with this rifle which was a best of 1.5" and an average of 2.5" at 100 yards. I will confess that I did use packing popcorn filler because the 40-90 BN is quite a large case and the fairly small powder charge of 22.5gn LT-30 left a lot of the case unfilled. I know that using the filler kind of goes opposite of the purpose of this whole thread about testing LT-30 powder as a replacement for 5744 without filler but in this case I was after the best accuracy I could get and I think I found it even if the filler was required. I guess in fairness I should try the same load without the filler and report on that but at the moment I am reveling in my success. This load turned the 40-90 BN into a full blown target rifle at least for moderate range. We will just have to test it to see at what range the alleged instability becomes a negative factor for longer range shooting. I could never understand why the generally accepted norm of today is that the big bottle neck Sharps cases were inaccurate but in the face of that the rifles that were produced by Sharps and Remington for the first international long range match at Creedmoor were chambered for the big bottle neck cartridges namely 40-90 and 44-90. Seems like we have lost something over time. Anyway this 40-90 BN has proven that it can shoot good and with the adjustable Ballard PP mold I can tweak it to drop a bullet length of exactly 1.25" the darling of the experts for a 1/18" twist barrel. Bullets from the Ballard PP mold cast in pure soft lead also make for a great hunting bullet for anything size appropriate for such a cartridge.
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Post by missionary on Jun 1, 2023 5:46:12 GMT -7
Howdy Dan Again thank you for all your testing with LT-30. The "twist tables" many people quote were written for artillery rounds. Now consider the vast difference of a hollow cast iron container that will be filled with explosives. Or partly with balls. Or fused with a long delay fuse or an air burst fuse. All sorts of variables to sort out. We won't get into variable charges of propellant but "short rounds" always were to be considered. Now add in that this is not a pinpoint bullseye projectile. As long as it hits within burst radius all is well. So then the twist formula works well enough for all the variations especially when there is a FO to adjust on target. So as General Patton was so apt to declare about Army Regs, "They are only guidelines". I do think for our case of projectile launching, RPM's far supersedes in our quest for pinpoint deliver especially at long distance. If a rod is stable at 100 yards, deliver that same projectile at 900 yards with the near same RPM and it should still be accurate. Problem can be the projectile supporting that initial kick in the base.
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Post by Bullshop on Jun 1, 2023 7:11:10 GMT -7
Horse shoes, hand grenades, and artillery. I have an old NEI mold for what I can only call a 40 Gov design because it looks like a 40 cal version of the arsenal 45/500 Gov bullet. This 40 cal version cast in pure lead weighs 410 grain and is 1.264" in length. That is very close to the prescribed 1.25" for 40 cal in 1/18" twist. If that bullet shoots well at 100 yards I will Lord willing try it at long range. It is exactly what I was hoping for in a bullet that is 400 + grains that will stabilize in my 1/18" twist. The standard recommended length for 1/18 is 1.25" at a weight of 370 grain. This bullet design packs the weight I want into a fairly short package but still has a reasonably efficient nose shape. Well at least they thought it reasonably efficient in 1873 when they designed the 45/500 Gov bullet for long range.
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Post by Bullshop on Jun 3, 2023 7:56:51 GMT -7
So I guess this shows that the 40 Gov NEI bullet will shoot well in the 1/18" twist. This was a duplex load using .5cc of LT-30 under 50 grain of surplus WC-870 ignited by a CCI - LRM primer. Interesting is that these NEI bullets were cast in pure lead at about BHN-5. This was with the last 4 bullets from the small lot cast to try. Lord willing I will make more of the same. I had only 4 left from about 25 that I made but used up testing other powders. I tried LT-30 alone as well as duplex loads with LT-30 and black powder but this duplex smokeless load gave the best preliminary results. Must make and try more !!! Picture of 100 yard target to follow. Attachments:
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Post by todddoyka on Jun 3, 2023 8:49:17 GMT -7
very good shootin!!!!!!!!!
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Post by Bullshop on Jun 3, 2023 9:28:24 GMT -7
Thanks Tod. That 2" north shot was more likely me than the load. It was way to overcast to chronograph this AM but I would guess the velocity around 1300 to 1400 fps. I used almost the same load when I shot at the Quigley shoot but in a 45-70 with 500 grain bullet and as I recall that was about the velocity. I might be wrong though as this is a bottle neck case in a smaller caliber so may generate higher pressure. The fact that the bullets were cast of pure lead will limit the velocity with good accuracy to something near 1500 fps so I think I will find that the velocity of this load will be something less than that. This duplex smokeless load always seems to generate about what a max velocity load would be with black powder and the same bullet weight. Max velocity given from most sources for the 40-90 BN with 370 to 400gn bullets with black powder is usually between 1400 and 1500 fps.
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Post by Bullshop on Jun 3, 2023 13:57:36 GMT -7
Oh boy here we go! I just found another old 40 caliber NEI mold that has been hiding in my stash. This one is a nice two cavity made of mehenite the copper iron alloy Walt used for his top of the line mold material. Like the other 40 Gov mold this one is the same design but where the one I shot this target with is 1.264" bullet length this one is another .010" longer at 1.274'. This one then will be the test. Honestly though I am now not certain of the rifling twist rate in this barrel. This rifle is on an Italian receiver that has been re-barreled by C. Sharps in Big Timber MT. to the 40-90 BN. The man I got the rifle from said it was a 1/18" twist but I am now not sure if he was correct. I plan to try this new longer bullet and that should tell something. I think also that I will just not rest until I try to do a cleaning rod measurement. Both things together should tell me something. We shall see! I would like it if this new even longer bullets shoots good in this rifle. If it does it will then surely be capable of long range.
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Post by shootist---Gary on Jun 3, 2023 19:02:05 GMT -7
Daniel, I sure wish that we lived closer, as I would be a witness to all of the research & then the testing that you do, trying to find the perfect match of powder & bullet for your rifles. It has to be very satisfying, when the final results of the testing show up on the target. Have fun.
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Post by Bullshop on Jun 4, 2023 5:37:35 GMT -7
Gary my friend it is no doubt a passion of mine. You might find yesterdays testing amusing. I have been reading about everything I can find about Schuetzen shooting and the loading methods used. There is much to be gleaned from those practices of the past. It may have been from Ned Roberts that said he tried duplexing with both smokeless powders, with black powders of different granulation, and with smokeless powders duplexed with black powders. He also said that sometimes he used smokeless powder for a priming charge with a black powder main charge as well as sometimes using black powder as a priming charge for a smokeless powder main charge. I had never before yesterday tried using a black powder priming charge with a smokeless powder main charge. No doubt from the picture I got good accuracy from the smokeless powder duplex load but that is quite a stiff load on the butt end of the rifle. Remembering what Ned Roberts said I thought I would try for a load using a BP priming charge with a main charge of WC-870 smokeless. I did just that and got very pleasing results. I didnt get three shots in one hole but still very good grouping. The load I settled on is using .7cc of FFFG black powder under 40 grains of the WC-870 and a CCI# 250 magnum primer. This load is reducing the main charge of WC-870 to 40 grains where the full smokeless load used 50 grain so this load is more pleasant at the butt end of the rifle. I am sure it also has less velocity than the smokeless load but in the accuracy game velocity is not king but velocity consistency is especially for long range. I will have to do more shooting with this new load to see just how consistent the velocity is. After all the years I have been at this it excites me to find a new undiscovered by me path to accuracy by a method that was long ago discovered by shooters of a past era but forgotten by those of the present.
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Post by Bullshop on Jun 4, 2023 5:53:22 GMT -7
Oh yea I forgot to mention that I did do the cleaning rod test to determine rifling twist rate and came up with 16.5" for several tries so looks like the man I got the rifle from may have been wrong about the 1/18" twist. If that is correct then I feel quite certain that this rifle will shoot well with the longest bullet I have described here. Also obviously I cast more of the 45 Gov bullet yesterday and is why I had more for testing. These are also cast in pure lead which apparently requires no seasoning time because I loaded and shot these as soon as they were cool enough to handle.
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Post by Bullshop on Jun 4, 2023 20:10:59 GMT -7
Sooooo with the new twist revelation at 1/16.5" I decided to cast up some of what we will call the big 40 because its the biggest one I have. These big 40 bullets weigh 430gn lubed and are 1.366" in length. I thought since they are 20 grain heavier than the 40 Gov bullet that I should adjust the load to stay on the safe side. After going through several different combinations of weights with both powder types I settled on a load of 1CC of FFG for the priming charge and 35 grains of WC-870 for the main charge. After about ten shots with this load I noticed the group opening some so for the last three shots of the day I decided to wipe the bore after each shot. The resulting group was I will guess at somewhere between 1.5 to 2" but I am pretty sure less than 2". That was after the sun had set but still with plenty of light to see the target through the peep sights. The wiping of the bore was with one patch between shots dampened with my new favorite BP solvent. This is made by mixing one part of white wall tire cleaner to three parts water. This stuff is amazing! One patch between shots is not too much of a pain in target shooting especially when it improves the consistency of the load. Its a "" I'd rather not but will if I have to"" kind of deal On close inspection of the holes on paper they look nicely round with no visible sign of tipping which points to my rifling twist measurement of 1/16.5" being correct much to my delight. As they say the proof is in the pudding and in this case the pudding is long range so what I need to do now is set the steel gong away out there and have at it. Sounds like too much fun to be legal !
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Post by missionary on Jun 5, 2023 3:28:50 GMT -7
Plus it is your Right to do so ! It is Wonderful how God will give His followers the delight of their heart.
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Post by Bullshop on Jun 7, 2023 16:16:59 GMT -7
Mike you put me to mind of Abraham and Izak. God didn't want to take away Abrahams second greatest love in his life he just wanted to know if Abraham was willing to give it up if God asked him to. I have asked myself that question but so far I have never felt that God has asked me to. Today I had to back up a bit to where I had earlier mentioned that when testing LT-30 loads in the 40-90 and just as I was getting to the point of ballistic uniformity the pure lead I was using for my bullets was failing. I mentioned that I felt that if I had been using something harder than pure lead that I may have gotten different results. Well after todays shooting it turns out that assumption was correct. Yesterday I had to cast an order for hard bullets so switched over to the hard lead pot. The order was for bullets that would run about BHN-25 after being quench cooled. The alloy air cooled should run about BHN-13 so while it was up and running I cast about 50 bullets with the big forty mold but air cooled them. I tried them today with the LT-30 powder and the results were astounding. I started a little too high for powder charge not that it was too high pressure to be safe but apparently too high for best accuracy. Slowly working back down in small increments I hit the sweet spot at 21.1gn of LT-30 with a CCI #250 LRM primer and the case filled with PP. My final shots for the day before rain ended testing was so good I wont even say how good but just say if it is repeatable I simply can not fathom that long bullet not being completely stable in flight. I am so tempted to now try this load at the 540 yard gong to see if drop numbers change at all from the pure lead bullets with the duple load. In his book DR. Mann stated that in his early testing he always got best accuracy with pure lead bullets when using black powder and always got best accuracy with alloyed lead when using smokeless powder. My first testing was with pure lead bullets but I veered somewhat from his absolute with my powder choices. I think from now on I will still use pure lead when looking at loads that may be used for hunting but for accuracy loads maybe alloyed bullets might be best unless as Dr. Mann said straight black powder is used. Anyway back to my point that was yes LT-30 did work a treat in the 40-90 once the right bullet hardness was found. Chalk up another point for the versatility of LT-30.
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Post by Bullshop on Jun 24, 2023 10:26:43 GMT -7
Tried LT-30 today in a new to me Sharps 50-70. I tried the traditional Lyman 515141 at about 430 grain and the RCBS 550 grain bullets. Both shot very well once I got close to the powder volume that began to generate enough pressure to get the powder to a fairly consistent burn. Starting out by taking a WAG at the volume proved me way off base. That 1/2" bore has quite a large expansion ratio! With 5744 the starting load in the first edition Accurate powders book they show 27gn as the starting load with the same bullet and 30 as max. Before looking in the book I started at 21gn which is a good load using 2400. With 21gn of LT-30 the first shot was a very light report and recoil and the second shot was a squib that stuck the bullet in the barrel. Slowly working up with the 425gn bullet I am getting good accuracy at 40 grain. This seems like about the limit for the pure lead bullets I am using but is shooting very good at 100 yards, On the steel RR tie plate swinger it takes it off the hooks nearly every time so is hitting with some authority. This rifle is a modern replica Sharps so quite strong but I would not shoot this load in my 1869 Springfield. I think its just too much for the vintage rifle. LT-30 apparently will not be a good choice for use in the original vintage rifle because even at the 40 grain charge the powder is not being completely consumed leaving burned but not completely consumed specks throughout the barrel. At the lighter charges while working the load up the load some of the powder left behind in the barrel was unburned and in its original kernel size. At 40 grains they are just small specks scattered through the bore but mostly gone. With a couple grain increase in powder charge that would likely clean up but then would also likely be over the top for pressure with my pure lead bullets that I like so much for hunting. As is there are no issues with chambering successive rounds so I will leave well enough alone. I like the load for this rifle as a hunting load. This rifle has no refined target sights but just a blade front sight with the original Laurance pattern rear sight with a V notch in the down position and a slider on the staff in the up position. Cant get much simpler than that. It shoots well enough for deer hunting to about 150 yards and with that fat pure lead bullet if I can keep shots inside 6" at 150 yards that will be more than adequate for deer. I like this rifle really well! It is in the standard plain business rifle pattern with basic sights, no frills but dependable in the field. There is good reason why it is stamped " Old Reliable" on the barrel. So we can chalk up another one for LT-30 with the 50-70. Its not an across the board powder for all loads in the cartridge but it sure seems like a keeper for loads in modern replica rifles that may exceed what should be used in vintage guns. And then with alloyed bullets a strong actions working up the load to a pressure that completely consumes all the powder leaving only a clean shiny barrel it may then rival in performance some cartridges that were developed specifically for use on the dark continent. Not too shabby for a cartridge that came out right at the close of our first uncivil war and may still be in civilian service in the second.
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Post by Bullshop on Jun 25, 2023 10:36:35 GMT -7
An interesting occurrence today with the 50-70 Sharps and LT-30 powder. I had previously loaded some ammo with the Lyman 515141 bullet and the load I had worked up to with LT-30 powder at 40 grain. Today I decided to chronograph that load and was not surprised at the velocity for a three shot string at 1504, 1524, and 1502 fps. I say not surprised because and as I had earlier stated this load seemed a bit too much for vintage rifles meaning the chamber pressure as well as the velocity would be higher than normal for black powder. A black powder load for the #515141 bullet should be closer to 1200 fps. I also had a small stash of bullets from a custom mold for a 600 grain Keith type bullet I designed at a customers request many years ago. It was a choice of tossing them back into the melting pot or shooting them and I chose shooting. I first again attempted the cleaning rod rifling twist test and got 24". The original Springfield 50-70 rifles had a 1/42" twist and would handle a bullet length of ever so slightly over 1". If I was right with cleaning rod test this barrel should handle a big honking bullet!!! I started at 25gn LT-30 with the 600gn bullet and worked up to 30gn which left the barrel in about the same condition as did the 40gn charge with the lighter 515141 bullet and it shot equally as well at 100 yards though the sight setting was way different. Now the interesting part. Until today I believed that small differences in cast bullet diameter had little effect on velocity. That apparently once again was a wrong assumption. I was certain that the same small differences with jacketed bullets could have quite a dramatic effect on chamber pressures but I thought it irrelevant with cast bullets cast in the same alloy. I will here list the short test results, 600gn Keith @ 514" 30gn LT-30 1125, 1138, 1143 fps
#515141 @ .514" 40gn LT-30 1504, 1524, 1502 fps
#515141 @ .512" 40gn LT-30 1469, 1418, 1449, 1439 fps
So it looks like the velocity difference between the .514" diameter at 1510 fps average and the .512" diameter at 1443 fps average for an average velocity change of 67 fps was caused only by changing the bullet diameter .002" all else being the same. Personally I was surprised by that because as I said I thought it would make no discernable difference. Apparently even with pure lead the slight increase in resistance to engraving the larger diameter of .002" caused a corresponding increase in chamber pressure to increase velocity by an average of 67 fps and this with pure lead mind you. Wow what a revelation for me !!! I will hence forth be ever so much more careful if making slight changes in not only bullet diameter but also to bullet hardness. I am now willing to bet that had the slight diameter increase been coupled with a substantial bullet alloy hardness increase that the velocity gap as well as the chamber pressure would be much wider. I am still learning !
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Post by shootist---Gary on Jun 25, 2023 11:23:10 GMT -7
Daniel, without having a chrony, When I had you make my 405gr. & 500 gr. bullets for my 1884 Trapdoor, you had me send you bullets that I forced thru the barrel with a hammer & wooden dowel rod to get an exact bore measurement for you to measure. The result was .458. You cast my bullets at .459. I loaded them in brass with 70 gr. FFG Goex compressed BP, with a veggie wad & 1 pc of newspaper disc behind the bullet. After I bought the Pedersoli "John Bodine" rolling block target rifle, I ordered some 535 gr. Postell bullets. Being that they weigh 35 gr. heavier, I then cut back on the powder 2 gr, to 68 gr. so they would be safer in the trapdoor. They were just as accurate, & still had noticeable 'kick'. Maybe I should have gone to 65 gr.
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Post by todddoyka on Jun 26, 2023 9:06:46 GMT -7
that 67fps really surprised me. i figure it would go 10 - 20+/-fps, not enuff to worry about. i learn more every day.
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Post by Bullshop on Jun 26, 2023 9:18:27 GMT -7
""Maybe I should have gone to 65 gr.""
I doubt that 3gn difference in weight of black powder would make much difference although I also thought that .002" difference in diameter of a pure lead bullet wouldn't make much difference either.
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Post by Bullshop on Aug 10, 2023 10:59:55 GMT -7
Have been absent here for a bit so want to add a couple new loads developed with LT-30. Have been mostly working with the 40-90 Sharps BN and the 50-70 gooberman lately. Have been shooting mostly BP duplex in the 40-90 using LT-30 as the kicker and it seems to excel for that purpose with a very small amount greatly aiding in a very clean burn of the BP. Yesterday I wanted to do a quick test of a bullet for stability so just wanted to shoot a few at 100 yards to check the holes on target to see if they would be round or otherwise. I went with a load of 26.5gn of LT-30 with a CCI # 200 LR primer and the case filled with styro packing popcorn under a 430 grain bullet. I fired three shots that at 100 yards with all three touching and apparently making round holes so spinning true at least at 100 yards. The group was centered withe the previous BP load that was clocked at 1530 fps average so must be at least close to that speed. Dont know if it was a fluke group because I was not trying to work up a load but just a simple test to see if the bullets were stabilizing. Perhaps at some point I should delve further with that. Next up was the Sharps 50-70 and a bullet I had never tried in a 50-70 before an NEI 520 grain round nose gas checked design. I cast those very soft and left off the gas checks as they are not needed at BP type velocity. Other loads I think I have mentioned here with this rifle used a 600gn paper patch bullet with 33gn LT-30 and the Lyman 515141 at about 430 grain with 40 gn LT-30 and both those loads shot really well so I decided to go about right between those 36.5gn LT-30 with this 520 grain bullet. End result was another winner for LT-30 powder in the 50-70 that produce about 100 fps less velocity than the 40-90 did giving us 1430 average velocity. Actually 1430 with a 520gn bullet is like a magnum load for a 50-70 but judging from the bore condition with some small powder specks visible I would say the pressure is moderate for the big Sharps made from modern steel but I would not use this load in a vintage trapdoor just to keep it safe. I took a couple boxes of these loads out into the hills yestereve and had a great time plinking away at distant rocks and sage out to maybe 700 yards or so. I am trying to get the feel for the Laurance sight and slider so much shooting is in order if this will be used for elk this fall which is pretty much what the current day dream is. So far what I have learned is the Laurance sight in the flat position is on at 100 yards. With the staff up but the slider down about 250 yards then the staff markings are about 100 yards off by + 100 so the 300 yard mark is on at 400 and so on. That is just a rough estimate but close. It may turn out that a good vernier sight gets mounted on this rifle before hunting and the rifle has proven worthy of the increased precision such a sight makes possible. We shall see when I requisition the minister of finance at the war department.
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Post by Bullshop on Aug 12, 2023 13:55:51 GMT -7
It seems that by now I have pretty well covered the usefulness of Accurate Powders LT-30 powder as a replacement for their older 5744 powder. When 5744 was readily available it became the gold standard for use in black powder cartridge rifle smokeless powder loads. I believe I have proven LT-30 to be equally well suited to the same task. Some folks that have established pet loads with 5744 may find they like LT-30 even better. For certain it has become a favorite of mine for a wide range of applications. So with that pretty well established even though I bet I could go on indefinitely listing new loads with LT-30 I think I have made my point with that powder and should now move on to others. So with that another powder once readily available but now hard to find that was once the gold standard for cast bullet rifle loads was formerly Hercules 2400 now Alliant 2400. On the powder burn rate chart in the Hodgdons annual data book 2400 is assigned number 50 on a chart that covers 162 different powders. Other powders I have used in the past but as replacement for 2400 now also harder to find are Alliant 410 # 48 on the chart and Alliant Steel # 55. Both those gave good performance but are now older powders and harder to find. The newest developments in powder are readily available some so new they are not even listed on the 2023 burn rate chart. Trying to keep a focus on availability I think we need to keep an eye on new powders because the powder companies will not continue to make the older powders once the new ones have established themselves. Remember the old guys that they sell the old powders to will be checking out and the young guys that market advertising tries to cater to will eventually become the old guys. It is a marketing tactic to convince the younger buyers that newer is better and not to settle for what grandpa used. So two of the newest powders that are right in the correct burn rate to be potential replacements for 2400 are Accurate TCM number 49 on the chart and Accurate 11 FS which is so new it has not yet been assigned a number on the chart but I will tentatively put it at about 54. With that established I will share what has turned out to be a pet load for a Thompson Center Contender pistol in 7mm TCU with a 10" barrel. Looking through all my available load data which is substantial there is very little date for the cartridge with cast bullets. Most load data for the cartridge is with heavy jacketed bullets and fairly slow powder burn rates. Going back to that gold standard for cast bullets with 2400 I decided to try these two potential replacement powders. First up was the slightly slower burning 11 FS. By the way the FS in the powder name stands for flash suppressed so likely a good choice in pistol length barrels. The best load with that powder and 150 to 160 grain cast bullets was worked up to 13.5 grain and gave excellent performance. No chrorographing was done but it smacked with authority at 100 yards and gave quite a jolt to the swinging railroad tie plate. I was quite happy with that load as with some effort on the shooters part it made consistent hits on said tie plate at 100 yards. For those that dont know what a tie plate is it is what the railroad rail sits on and it sits on the tie then the rail spiked to the tie with spikes going through the tie plate. Since it holds up the weight of a train it is a thick heavy steel plate about maybe 7" x 11" and quite thick so quite heavy so takes quite a bit of bullet energy to make it swing vigorously. Feeling pretty good with that load I also wanted to try the TCM powder which as I said is $ 49 on the burn rate chart with 2400 being # 50. As the name would imply TCM powder was developed specifically for use in the 22 TCM cartridge which is a 22 caliber cartridge based on the 223 case but shortened to have about 22 hornet powder volume and als to have a cartridge length that will fit standard 1911 clips. Since it has 22 hornet powder volume and 2400 powder was developed for the 22 hornet it seems like it should be a viable replacement. It turned out that the TCM powder performed even better than the 11FS in the 7mm TCM with my 150 to 160 grain cast bullets. With the TCM powder 11 grains was the best charge weight for both cast bullet weights used. If I had to pick between the two powders for this one use I think that the TCM gave slightly better accuracy at what I would guess at this point to be nearly as high velocity. The TCM load made hitting the 100 yard swinger boringly common and made that heavy tie plate dance pretty good too. Something else learned today is about bullet design for the 7mm TCU cartridge. The two bullets I first used are both bore riders that have a short full diameter length so can be seated with the gas check staying in the case neck. I found a stash of bullets from a Saeco mold that are more a conventional design that had to be seated more deeply into the case in order for the action to close and so then had the gas check and lube groove seated past the case neck and into the case exposed to the powder. Pondering that for a moment I had a " I wonder what if " moment. The idea I had was to nose size the 7mm bullets in a .277" die for the 270 win. I thought that should give me an adjustable length nose section that should snuggly ride the lands and I could adjust that length so that they could be seated to keep the gas checks in the case neck where they belong. Short story is it worked like a charm and they were equally as accurate as the other two bullets. A big bonus to the nose sized bullet is that it has the widest meplate of the three bullets tried so likely the best suited for hunting game appropriate in size for the cartridge say up to coyote size. I can see myself out calling coyotes with nothing to carry heavier than this 10" pistol. Lots to like there !
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Post by Bullshop on Aug 13, 2023 10:15:48 GMT -7
This AM I did another very simple but revealing test. It involved testing three powders, 2400, 11-FS, and TCM. Since I had the powder drop set to throw 7.5 grain of TCM powder I thought I would start by comparing the weight to volume of the three powders and just as expected from each powders assigned burn rate with the same volume setting they were TCM- 7.5gn,--- 2400 - 7.7gn, and 11-FS - 9.2gn. Next up was to chrono the three powders with the same weight charge at 7.5gn and the results were very interesting in that they were much higher velocity than expected but still stayed at what would be expected from their burn rate numbers. The chrono data went like this, TCM --- 2616, 2605, 2601 2400 --- 2539, 2501, 2485 11-FS --- 2406, 2357, 2310 Grouping for these each with 3 shots was TCM --- farthest apart.925" closest together .671" 2400 --- farthest apart 4.327" closest together 3.854 11-FS --- farthest apart 1.820 closest together 1.756" That was almost shocking the difference in grouping between TCM and 2400 since they are near twins in burn rate. I simply can not explain it. TCM made a spectacular showing in velocity and grouping at over 2600 fps velocity and under 1" group. I should also mention that there was also another test going on at the same time which was a test of a new bullet alloy containing nickel Babbit. Nickel Babbit is very hard and the small percentage of nickel raises the shear limits of the alloy with hopefully higher velocity potential. Mayhaps it did ! This was just a short simple test but if the trend continues I may have a new favorite powder for my beloved 22 hornet cartridge. Oh I should also mention the bullet used, it was a Modern Bond 50 grain round nose gas checked sized to .225". As for alloy hardness with the nickel babbit added and without testing all I can say is hard, too hard to mark with a thumbnail. OOPS ! I forgot to mention this was in a 22 hornet.
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Post by missionary on Aug 13, 2023 19:14:32 GMT -7
TCM is looking like a very good substitute ... so far. I did notice Powder Valley has a stock of 2400 up for sale.
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Post by Bullshop on Aug 13, 2023 19:52:03 GMT -7
After todays test I am not sure if I want to buy any 2400. This was just one simple test though and 2400 may well prove to be better for cast bullet rifle loads for larger case cartridges. Its going to take a lot more testing to find out. The TCM is a fine ball powder where as 2400 is a small grain extruded powder. From my past experience ball powders usually are harder to ignite and do better with magnum primers. Ball powders also use burn deterrents to control burn rate rather than grain size and shape as with extruded and flake powders. I believe the deterrent coatings are the reason ball powders have previously been harder to ignite but with new powder technologies maybe no longer true. I tried the 11-FS in the 221 fireball this afternoon with the last few of those bullets made with the nickel babbit alloy. I started with 13.5gn and group was not impressive. The primer looked a little too flattened for normal cast bullet loads so I dropped the charge to 12 grain and shot a tight little 3 shot well under an inch group. I can already see that the 11-FS is not a replacement for 2400 because its quite some slower burning closer maybe to WW-680 or IMR-4227 but it is in the right burn rate for small case rifle cartridges and probably magnum pistol cartridges. I need to make more of those Modern Bond 22 bullets and do some more shooting with those in the 221. I also want to chrono that load and see if it is faster than the 2600 fps 22 hornet load. Any cast bullet loads doing over 2600 fps and holding sub MOA accuracy is pretty impressive at least to me it is. About 40 years experience shooting cast bullets has shown me that when you pass about 2100 fps accuracy becomes more finicky, not impossible but more difficult.
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