Post by Bullshop on Aug 7, 2020 17:13:05 GMT -7
Today brought The Bullshop a fun and interesting opportunity to work with a fine old Savage model 99 in 303 Savage. A customer up from Idaho brought it in to have some ammo made for it so work today was less work and more fun than usual This is a fine old Savage with full octagon 26" barrel.
I had enough time to spend on this project to also do a comparison with the 30-30 using the same bullet and powder with the same powder charge. Loads for the 303 Savage are hard to pin down and there is no shortage of disagreement as to how the two cartridges compare for load data. This was a great opportunity to find out first hand since we also had a 30-30 on hand for testing.
The load of 30.5gn of Accurate Arms # 4350 was first worked up in the 303 using the RCBS mold 30-180 FN-GC with the actual weight being 190gn and sized to .310". The target shown fired at 50 yards using the factory buckhorn sight as can be seen leaves little to be desired. The rifle is equipped with a vintage Lyman tang sight but this sight was set for a longer range and I didn't want to change the setting. I would guess it was set for 200 yards since the buckhorn sight shot about 1.5" high at 50 yards.
This load is ever so slightly compressed when the RCBS bullet is seated to crimp in the crimp groove in new PPU brass. This gives an OAL nicely compatible with the rotary magazine of the Savage rifle. The ammo was finished off using the Lee Precision factory crimp die to just slightly turn the case mouth into the crimp groove so there is no edge at the case mouth to interfere with feeding. All worked out well and the so loaded rounds feed as slick as you please.
With this load the long 26" barrel of the savage rifle gave an average of 1804 fps velocity with a respectably low extreme velocity spread. So that was it job over accept to make 200 more rounds for the customer. But wait thinks I, what if? Yea its already set up, go for it. So with Joy's permission to use her 30-30 and the powder measure set up to throw 30.5gn AA-4350 , RCBS bullets on the loading bench and the chronograph ready and waiting it was a natural to follow through with the 30-30 comparison.
So anyone else that has ever questioned what load data to use for the 303 Savage should appreciate this. The Marlin 30-30 with 20" barrel with the same load of 30.5gn AA-4350 gave an average velocity of 1786 fps. That is 18 fps slower than the 6" longer barrel of the Savage rifle, interesting!!!
Our Lyman 45th edition load data book gives a velocity of 1791 fps at 29,400 cup in the 30-30 with a 190gn jacketed bullet with a charge of 30 gn of IMR-4350. Most powder burn rate charts will show IMR-4350 and AA-4350 side by side at about the same burn rate and I have found the two powders to be interchangeable. So data from the Lyman book with a bullet of the same weight although jacketed gave a velocity plumb smack in the middle between the velocity we got but with .5gn more powder. Pretty close though which brings up another topic for discussion being """ in what way is pressure affected when swapping data between jacketed and cast bullets""" Not for now but something to be discussed.
As for the load used it filled both the 303 case and the 30-30 case to the same level allowing very slight compression with the bullet seated the same in both cases.
It seems to be generally considered that the 303 case has a slightly greater volume than the 30-30 but it also seems generally considered that the powder charge for the 303 should be reduced from the 30-30 data. That logic defies the involved physics especially considering that the model 99 Savage is unquestionably stronger than either the model 94 Winchester or the model 336 Marlin
I think my short test here today would indicate a slightly lower pressure in the 303 than in the 30-30 considering that we only saw an 18 fps velocity gain for the 6" longer barrel and that much more barrel length especially with this slow burning powder should in itself account for at the very minimum of 100 fps.
Anyway at the end of the day with this powder and this bullet I feel quite comfortable saying the data is interchangeable between the two cartridges. Perhaps with faster burning powder the results may be quite different but the physics have to apply. The case volumes seem very very close at least with the FC 30-30 brass and the PPU 303 brass I used today. The outside dimensions are different with the 303 having a larger head diameter but the 30-30 makes up for that difference by having its shoulder farther forward. For the involved physics what matters is the internal volume and in todays test they were virtually the same
So there you go interesting stuff for anyone head scratching on loads for their 303 Savage.
I had enough time to spend on this project to also do a comparison with the 30-30 using the same bullet and powder with the same powder charge. Loads for the 303 Savage are hard to pin down and there is no shortage of disagreement as to how the two cartridges compare for load data. This was a great opportunity to find out first hand since we also had a 30-30 on hand for testing.
The load of 30.5gn of Accurate Arms # 4350 was first worked up in the 303 using the RCBS mold 30-180 FN-GC with the actual weight being 190gn and sized to .310". The target shown fired at 50 yards using the factory buckhorn sight as can be seen leaves little to be desired. The rifle is equipped with a vintage Lyman tang sight but this sight was set for a longer range and I didn't want to change the setting. I would guess it was set for 200 yards since the buckhorn sight shot about 1.5" high at 50 yards.
This load is ever so slightly compressed when the RCBS bullet is seated to crimp in the crimp groove in new PPU brass. This gives an OAL nicely compatible with the rotary magazine of the Savage rifle. The ammo was finished off using the Lee Precision factory crimp die to just slightly turn the case mouth into the crimp groove so there is no edge at the case mouth to interfere with feeding. All worked out well and the so loaded rounds feed as slick as you please.
With this load the long 26" barrel of the savage rifle gave an average of 1804 fps velocity with a respectably low extreme velocity spread. So that was it job over accept to make 200 more rounds for the customer. But wait thinks I, what if? Yea its already set up, go for it. So with Joy's permission to use her 30-30 and the powder measure set up to throw 30.5gn AA-4350 , RCBS bullets on the loading bench and the chronograph ready and waiting it was a natural to follow through with the 30-30 comparison.
So anyone else that has ever questioned what load data to use for the 303 Savage should appreciate this. The Marlin 30-30 with 20" barrel with the same load of 30.5gn AA-4350 gave an average velocity of 1786 fps. That is 18 fps slower than the 6" longer barrel of the Savage rifle, interesting!!!
Our Lyman 45th edition load data book gives a velocity of 1791 fps at 29,400 cup in the 30-30 with a 190gn jacketed bullet with a charge of 30 gn of IMR-4350. Most powder burn rate charts will show IMR-4350 and AA-4350 side by side at about the same burn rate and I have found the two powders to be interchangeable. So data from the Lyman book with a bullet of the same weight although jacketed gave a velocity plumb smack in the middle between the velocity we got but with .5gn more powder. Pretty close though which brings up another topic for discussion being """ in what way is pressure affected when swapping data between jacketed and cast bullets""" Not for now but something to be discussed.
As for the load used it filled both the 303 case and the 30-30 case to the same level allowing very slight compression with the bullet seated the same in both cases.
It seems to be generally considered that the 303 case has a slightly greater volume than the 30-30 but it also seems generally considered that the powder charge for the 303 should be reduced from the 30-30 data. That logic defies the involved physics especially considering that the model 99 Savage is unquestionably stronger than either the model 94 Winchester or the model 336 Marlin
I think my short test here today would indicate a slightly lower pressure in the 303 than in the 30-30 considering that we only saw an 18 fps velocity gain for the 6" longer barrel and that much more barrel length especially with this slow burning powder should in itself account for at the very minimum of 100 fps.
Anyway at the end of the day with this powder and this bullet I feel quite comfortable saying the data is interchangeable between the two cartridges. Perhaps with faster burning powder the results may be quite different but the physics have to apply. The case volumes seem very very close at least with the FC 30-30 brass and the PPU 303 brass I used today. The outside dimensions are different with the 303 having a larger head diameter but the 30-30 makes up for that difference by having its shoulder farther forward. For the involved physics what matters is the internal volume and in todays test they were virtually the same
So there you go interesting stuff for anyone head scratching on loads for their 303 Savage.
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