Powder comparison help needed

[sniper208]

I shoot a .30-06 with an actual barrel length of 21 29/32" (stamped 22"). I have some 200 grain Partitions that I loaded in 1991 for a rifle I no longer own (exceptional performance) and they don't group well in my current rifle. I have some custom load data configured (Quick Load) for my rifle with a different powder. My bullet puller destroys the bullets so pulling them and reloading with the new data won't work. What difference can I expect shooting the old load in my rifle relative to velocity, energy and pressure?

Old load:
IMR 4831, 53.2gr, 3.335" OAL, Remington brass, Remington LR 9 1/2 primers

New load (low-end sweet spot):
IMR 4895, 47.9gr, 3.335" OAL, same components

Thanks!

 

[DrMike]

The slight marring with a collet-style bullet puller shouldn't destroy your bullets. Any minor marks resulting from a kinetic puller would be insignificant in degrading accuracy.

With a 200 grain PT, 47.9 grains of IMR 4895 yields a velocity of ~2539 fps, and 53.2 grains of IMR 4831 yields a velocity of ~2531 fps. Both of these calculations are in a 22 inch barrel. Velocity differences for these two loads would be statistically insignificant.

 

[sniper208]

Thanks Dr. Mike! I don't have that many rounds so I'll keep them "as is" and deal with the insignificant velocity difference. I've got an issue with the bullet puller though but that's a different issue. It's not a slight marring of the bullet. I have to tighten the collet so tight it takes a .308 bullet and from the tip to the mid-point half way down the projectile it looks like a .243! Great info - thanks!

 

[gerry]

One hhing I do with older loads is to seat the bullet slightly deeper with your seating die so the bullet breaks free since it's been held that way for so long. It will make a loud crack when you do this and you will find it comes out much easier.

 

[sniper208]

I tried to seat the bullet deeper, but the seal didn't break. Perhaps I didn't try to seat it deep enough. Either way, I'll just hang on to these. They shoot accurately enough to put meat on the table. I shot the bullets I destroyed - what a joke! I got a 4" group at 100 yards - hardly to my standards. I shot another five of the old load with bullets intact and got 1.5" groups. Not great, but acceptable for now. Thanks for the help guys!