Bill*B
01-27-2018, 08:11 PM
Yeah, I know its a cast bullet site. Still...
I'm posting this because my CZ 527 in .223 tempted me to load J-words, because "its just so easy!". Now, we all know that our barrels will outlast us, when shooting cast - but did you ever wonder what sort of barrel life J-words would allow?
I entered Quick Load estimated pressure and velocity into the Accurate Shooter. com barrel life spreadsheet, substituting VV N110 for SR 4759, VV N105 for Steel, and a blend of ADP 100 (velocity) and Unique (pressure) for SR 4756. A barrel length of 22" was specified. The powder heat potential for 4895, 3031, H4198, and IMR4227 was entered from published data, and estimated for SR4759, Steel, and SR4756. These loads are all with a 55 grain bullet, in caliber .223 Remington.
IMR 4895 - 25.5 grains - 100% load density - about 3,000 fps - 4,000 shots for fine accuracy.
IMR 3031 - 23.5 grains - 99% load density - about 3,000 fps - 5,000 shots.
H 4198 - 20.5 grains - 85% load density - about 2,900 fps - 6,000 shots.
IMR 4227 - 17.5 grains - 75% load density - around 2,800 fps - 7,500 shots.
17.0 grains - 73% load density - about 2,700 fps - 8,500 shots
SR 4759 - 13.5 grains - 75% load density - about 2,500 fps - 17,000 shots!
All of the above are either from published .223 data, or can be extrapolated from published .222 data by adding 5% to the .222 charge weight.
However - the following loads are Quick Load estimates only, with NO published, tested data to correlate - you are on your own with these! Do be aware of the controversies swirling about reduced loads before trying them - I show them only to illustrate how lower velocities can extend the barrel life by a factor of 5 or even 10, if the spreadsheet assumptions are correct.
Alliant Steel - 10.5 grains - 60% load density - about 2,000 fps - 20,000 shots
SR 4756 - 6.5 grains - 40% load density - about 1,800 fps - 50,000 shots before loss of fine accuracy.
Hey! - these are just estimates of estimates. Take them with a grain - or maybe a block - of salt.
I'm working on a decent cast load with my own Lyman 225438 bullets, and have several hundred NEI #2 on order from Bullshop. Let's hope that one of these pan out! But darn, the flesh is weak, and I confess to having tried that SR 4759 load with Speer 55 grain J words. Accuracy was decent, a solid 2 MOA (with me behind the rifle). I doubt that I will burn out the barrel in my remaining time, even if I shoot more of these. Do these figures mesh with your own experience?
I'm posting this because my CZ 527 in .223 tempted me to load J-words, because "its just so easy!". Now, we all know that our barrels will outlast us, when shooting cast - but did you ever wonder what sort of barrel life J-words would allow?
I entered Quick Load estimated pressure and velocity into the Accurate Shooter. com barrel life spreadsheet, substituting VV N110 for SR 4759, VV N105 for Steel, and a blend of ADP 100 (velocity) and Unique (pressure) for SR 4756. A barrel length of 22" was specified. The powder heat potential for 4895, 3031, H4198, and IMR4227 was entered from published data, and estimated for SR4759, Steel, and SR4756. These loads are all with a 55 grain bullet, in caliber .223 Remington.
IMR 4895 - 25.5 grains - 100% load density - about 3,000 fps - 4,000 shots for fine accuracy.
IMR 3031 - 23.5 grains - 99% load density - about 3,000 fps - 5,000 shots.
H 4198 - 20.5 grains - 85% load density - about 2,900 fps - 6,000 shots.
IMR 4227 - 17.5 grains - 75% load density - around 2,800 fps - 7,500 shots.
17.0 grains - 73% load density - about 2,700 fps - 8,500 shots
SR 4759 - 13.5 grains - 75% load density - about 2,500 fps - 17,000 shots!
All of the above are either from published .223 data, or can be extrapolated from published .222 data by adding 5% to the .222 charge weight.
However - the following loads are Quick Load estimates only, with NO published, tested data to correlate - you are on your own with these! Do be aware of the controversies swirling about reduced loads before trying them - I show them only to illustrate how lower velocities can extend the barrel life by a factor of 5 or even 10, if the spreadsheet assumptions are correct.
Alliant Steel - 10.5 grains - 60% load density - about 2,000 fps - 20,000 shots
SR 4756 - 6.5 grains - 40% load density - about 1,800 fps - 50,000 shots before loss of fine accuracy.
Hey! - these are just estimates of estimates. Take them with a grain - or maybe a block - of salt.
I'm working on a decent cast load with my own Lyman 225438 bullets, and have several hundred NEI #2 on order from Bullshop. Let's hope that one of these pan out! But darn, the flesh is weak, and I confess to having tried that SR 4759 load with Speer 55 grain J words. Accuracy was decent, a solid 2 MOA (with me behind the rifle). I doubt that I will burn out the barrel in my remaining time, even if I shoot more of these. Do these figures mesh with your own experience?