The Firing Line Forums - View Single Post - Question for those chasing grouping sizes.....

Sarge43 · November 9, 2011, 12:40 PM

I am a long time pistol shooter and have recently gotten into rifle shooting again. I am hooked on chasing group sizes. I have not reloaded rifle cartridges before, but have loaded pistol ammo in the past. The question is this:
How much can individual bullet weights be off before you see a difference on the paper? I am reloading .308 Win and using Nosler 165 grain ballistic tips. In weighing the individual bullets, most of them are within 0.2 grains of each other, but once in a while, you'll get one that is up to 0.5 grains heavier/lighter. In a perfect world, every round you load will be EXACTLY the same, I understand that, but in reality, what is an "acceptable" variance in bullet weight with all other factors being equal?
Also, as a follow up question - (I feel like the rifle noob that I am here asking this) What affect can poor/inconsistent primer seating have on accuracy? In pistols with ranges normally at 25 yards, this isn't a real factor, but out at 600 yards, can this drastically affect accuracy?
Thanks in advance for the help and answers!
Sarge

November 9, 2011, 12:40 PM	#1
Sarge43 Senior Member Join Date: November 6, 2008 Location: Kansas City Posts: 503	Question for those chasing grouping sizes..... I am a long time pistol shooter and have recently gotten into rifle shooting again. I am hooked on chasing group sizes. I have not reloaded rifle cartridges before, but have loaded pistol ammo in the past. The question is this: How much can individual bullet weights be off before you see a difference on the paper? I am reloading .308 Win and using Nosler 165 grain ballistic tips. In weighing the individual bullets, most of them are within 0.2 grains of each other, but once in a while, you'll get one that is up to 0.5 grains heavier/lighter. In a perfect world, every round you load will be EXACTLY the same, I understand that, but in reality, what is an "acceptable" variance in bullet weight with all other factors being equal? Also, as a follow up question - (I feel like the rifle noob that I am here asking this) What affect can poor/inconsistent primer seating have on accuracy? In pistols with ranges normally at 25 yards, this isn't a real factor, but out at 600 yards, can this drastically affect accuracy? Thanks in advance for the help and answers! Sarge __________________ Exotic wood addict and grip maker www.shop.thefinergrain.com