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Post by todddoyka on Jan 18, 2021 13:59:45 GMT -7
i bought a 6.5 carcano (could be a model 38? made in 1947) at an auction for $50. i stripped down the bolt and cleaned her up. it took me two days to strip the bore, including soaking it(shooter choice mc7) overnite. the rifling has some issues, it has 3 different spots(about a 1/8 - 1/4" each different spots ) that the rifling was smoothed. other than that, the rifling is around 70-80% good. i still have to slug the rifle but i'll be using cast boolits. from what i've read, it could be .2675" bore size. i guess i have to wait and see. it will be a couple of years, i have Springfield armory and mausers actions that need built. so i probably will set in the safe after i'm done cleaning it.
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Post by Bullshop on Jan 18, 2021 19:48:33 GMT -7
My customers shooting the Carcano are shooting our 130 gn bullets at .269" diameter and report very good results. I believe the Carcano rifles used gain twist rifling. I think I read that Harry Pope tried gain twist for a while but gave up on it as being to damaging to bullets for top accuracy and Harry Pope was all about top accuracy. Gleaning information from customers I believe the Carcano rifles have extremely long throats. That is likely why our bullets are shooting good in them because both our designs are Loverin with long bearing surface. These can be seated out far enough to get some land engagement to give the front end of the bullet some guidance. Bore ride designs will likely not do as well.
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Post by todddoyka on Jan 18, 2021 20:02:15 GMT -7
from what little i've read, mine is not gain twist, but it is a 1 in 10" twist. i haven't chamber cast or slug the bore yet, but i believe it has a long throat too.
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Post by Bullshop on Jan 19, 2021 9:09:53 GMT -7
I think the military load used a long parallel sided 160gn round nose bullet. I might be wrong or something changed at some time because a 1/10" twist would not be well mated to a long 160gn bullet. The standard now is a 1/8" twist for a 140gn bullet though todays 140gn bullets with long pointed nose and boat tail in 6.5mm may well be longer than the original military 160gn round nose and so would require a faster twist. When I built my 6.5/06 Ackley I went with a 1/10" twist because I wanted it specifically for the Sierra 107gn match bullet and I wanted the highets possible velocity for that bullet . Interestingly in 25 caliber the standard twist rate is 1/10" and the 25-06 handles long pointy boat tail bullets at 120gn quite nicely. A couple interesting historical notes about the caliber, when Chas Newton came out with the 256 Newton he had intended it to be 25 caliber. He imported some Crupp barrels from Europe but they were in the European 25 caliber at .264" groove with a .257" bore. In Europe they generally designate caliber by bore diameter not by groove diameter as we do. Anyway Mr. Newton went on to create one of the most famous cartridges ever designed, it just took a wee bit over 100 years to catch on. I speak of course of the 6.5mm Creedmoor which is nothing more than a 256 Newton with slightly tweaked case dimensions. Another historical tidbit I found interesting about the 6.5mm caliber comes from the Book "" The Bullets Flight"" by Dr. Franklin Mann. In his quest for high velocity before the turn of the century a century ago he used what he called a base band bullet. Essentially he used a bullet that was bore diameter .257" for its entire length with a band at its base of groove diameter. Think of it as a 25 caliber bullet wearing a 26 caliber gas check. The reason was to reduce the resistance of the bullet being engraved as it entered the rifling to have a less steep climb in chamber pressure and hopefully achieve higher velocity. This is the same principle I used in building my 6.5/06 Ackley in that the slower than standard twist offered less resistance so has a less steep pressure climb for a longer push and hopefully higher velocity. In my goal I was successful in that with my absolute maximum loads with my chosen bullet weight ( 100-107gn ) from the 30" Pachnor barrel the velocity is 3700 fps. That is a higher velocity than published data gives for the 264 Win Mag with the same bullet weight but the data for the 264 WM is generally from a 26" barrel with the standard 1/8" twist. Interesting stuff !
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Post by todddoyka on Jan 19, 2021 16:56:11 GMT -7
it is interesting. i learned something new today.
i had a 6.5 creedmoor in a tc encore with a 15", 16 1/4" and 23" MGM barrel. it was accurate as heck. i used 120gr nosler bt and 140gr hornady sst. i used hodgon superforamnce as my powder. my mind is fuzzy, i believe it was a 1 in 8" twist. anyway the bullets were going 2600-2700fps, any more than 2800fps you have a grenade going off. not so good for deer.
i had a 25-06 in tc venture, it was accurate but the plastic stock and the plastic magazine wasn't for me. i killed a couple of deer with tho. i think it was a 115gr nosler bt and imr4064 going 2750fps.
i noticed that if you use a ballistic tip or sst in whatever caliber you choose and you hunt deer close up, you're better off if the velocity is mild. i used a 130gr nosler bt with a max imr4320 going 3000+fps. it was a grenade going off. you can't see it, but my avatar was shot at 10-12 feet with the 270. its shoulder was smashed and the lungs and heart were chunky soup. the offside was not touched by fragments. the entry wound was about .277" and it did not leave a blood trail. i have shot many deer with that load and in every case, i threw away the shoulder because it was so blood shot.
but going under 2800fps, the bt and the sst worked well. they were thru and thru close up on deer. i haven't shot a deer with jacketed bullets for about 8 years now. but cast boolits are killers!!!
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Post by Bullshop on Jan 19, 2021 18:13:34 GMT -7
For a time I had and hunted with a first model Newton rifle chambered in 256 Newton. I shot one elk with that rifle. I dont remember the load but I do remember the bullet a 129gn Nosler partition and the velocity was 2900 fps. The bull I shot with it was a smallish rag horn something like a 4x5 but I dont remember for sure . I do remember the shot though as if it were in a picture. I jumped the bull from where he was bedded by a fence. He ran straight away and I had serious doubt about such a small bullet taking such a shot. I was firmly in the Elmer camp even then. He ran toward some sparse timber and when he was about 75 yards away he glanced back to see what had spooked him. When he did that he exposed his right flank enough to see the yellow hair there young bulls have at that time of year. I had a solid rest on a fence post and was watching him through the scope put distance between us as I was very reluctant to try the rear end shot with that tiny bullet. When I saw that yellow I was on it quick because in another 25 or so yards he would have started down hill and out of sight. When I touched off the shot at the right flank the bull crashed in a heap and skidded on his lips to a stop. I put another round in the chamber and watched him . He struggled to get his front feet under him and just as I was about to shoot again he dropped and it was over. The shot was perfect just barely grazing the hind quarter just enough to shave hair but not cut hide. The bullet caught the right flank right in the yellow patch. When I skinned out the bull I found the bullet in the left side of the neck about half way up the neck. That was a lot of penetration for a 129gn bullet and the cartridge and caliber earned from me all the respect it was due. The only other game I have taken with the 6.5mm caliber was another elk with the 6.5/06 Ackley. The shot was at 673 yards and the load was the 100 gn Hornady SST at the max muzzle velocity for that rifle and bullet 3700 fps. The hit was a broad side high lung shot and the large cow did about the same as the bull shot with the 256 Newton. She collapsed at the hit and struggled for a few seconds to get her front feet under her but never made it. On skinning out the cow I found what was left of the bullet a thin flat disk just under the hide on the opposite side . Again the caliber performed admirably and added a few more points of my respect. I should note that had the shot been close the outcome would surely have been different. The place I was hunting is wide open with not a tree in sight for a mile and this was exactly the type of hunting I built the rifle for to sit and glass, spot, range, and shoot. Oh and I should also mention for this type of shooting I use a home made cross stick inside the sling so it holds the rifle up without touching it. I then plant the elbow of the trigger hand firmly into my right leg while sitting and hold the sticks with my left hand with the index finger of the left hand over top of the barrel. This makes for a very steady hold in the field.
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Post by missionary on Jan 20, 2021 5:38:32 GMT -7
Good Morning Dan How long / how any rounds did you practice before the 673 yards hunting shot ? I remember from some past post you wrote about the practice you put into that rifle / load.
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Post by Bullshop on Jan 20, 2021 9:31:37 GMT -7
Well I didnt do a lot of group shooting once the load was developed to my satisfaction. If you recall though I did spend that summer shooting rock chucks from the reapers roost at random ranges between 600 to 800 yards. From the roost out to an irigation ditch that is 600 yards away is flat hay fields so no chucks but lots of gophers. From the ditch to the top of the bluff behind it is another 300 yards. The chuck shooting starts at the ditch where they come down from the bluff for water. The first chuck I shot at 600 was right at the end of a farm bridge crossing the ditch. I have lasered several locations from the bridge on up the bluff and committed them to memory so I know what sight corrections are if quick shots are required. The bridge was the first of those so I know the near side of the bridge right where the chuck was sunning is exactly 600 yards as measured with my Swarovski range finder. My first shot on a chuck from the roost was right at 600 and I was amazed at the destructive power that little 100gn bullet had at that range. It spread that chuck out in an area several feet wide with blood and gut content spatters a few yards away. That is why I said that this rifle and load is not good for close shots. Its practical range for big game starts at about 500 yards. I had also intended it for long range coyote shooting in late winter when we often see them from roads at quite long ranges where they feel quite safe being out in the open. This time of year is mating season and is when the big males are most vulnerable. Just like in buffalo hide hunting the bigger the hide the higher the value.
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Post by missionary on Jan 20, 2021 11:14:18 GMT -7
T thought this would be a good place to repeat that information so others would understand you had already used that rifle / load and was well used to how it shot through long ranges.
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Post by Bullshop on Jan 20, 2021 12:38:26 GMT -7
Definitely ! There is a lot of prep work that goes into the successful long range shot. It is not the first summer spent in preparation for a single shot in the fall. I recall another summer spent with a 6.5x57 rifle I had back a ways in tuning the rifle and load to my satisfaction then field testing the results in preperation for a caribou hunt. The hunt location was the AK pipeline corridor. My set up point was on a rise overlooking a long dip in the road that went maybe 1000 yards to the next rise that I could not see over. I laid a sleeping bag on the ground frozen from January Alaskan interior sub zero temps. On the bag went sand bag rests my Swarovski binoculars and range finder Kestral weather station and a ballistic print out from my computer program . I spent the morning ranging objects that stood out easily seen and started memorizing their ranges. The corridor is not very wide so it only takes them a few steps to cross it so you must be ready for the shot when it comes. When my shot came it was a nice bull that stepped into the corridor and stopped at something like 630 yards. It was standing right beside one of my memory markers so I already had the range and corrections in my head as I had been studying them all morning. I was prone on the sleeping bag and steady on the rest bags. The shot was a perfect heart lung broad side shot and the bull took a few steps and piled up. Just then another bull stepped into sight standing beside the downed bull looking at him as if to say get up we have to go. My next shot dropped the second bull in his tracks with a frontal shot as he was facing exactly toward me looking at the downed bull. That filled both my tags and ended the hunt. Those couple successful shots took a summer of preparation. As I was gathering up my equipment two GI's from FT Greely came into the corridor where I was and asked if this was a good place to hunt caribou. I told them I had just shot two and pointed in the direction and low and behold there was another bull standing there. The only one of the GI's with a rifle aimed and fired and I saw his bullet hit about 30 feet short of the caribou and I told him so. He said there was no way he missed by 30 feet so I asked him what range his rifle was zeroed for and he didnt know. He said he had just bought it the day before and had it bore sighted at the store. I began to tell him how much preparation went into my shots but he became agitated and walked off saying "" I know dam well I didnt miss by 30 feet"" Well ya cant educate the masses so I just went about collecting my gear and caribou. BTW the load in the 6.5x57 rifle was with a 140gn Hornady spt-bt bullet at 2700 fps MV. Sure did the trick !
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