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Bart B. · August 30, 2012, 08:54 AM

I trim new brass to 10 thousandths less that SAAMI spec and uniform the case mouth. Then chamfer mouths with a No. 5 Easy Out which makes a much better angle that standard deburring tools. Then run a bore brush in a drill in and out to slighty radius the inside sharp edge so no bullet jacket metal gets scraped off when they're seated.

Turn necks if they've got more than 1 thousandths spread in thickness. No other brass prep I've tried makes any difference getting 3/4 moa accuracy at 1000 in my match rifles.

Full length sizing dies are all I use, but I keep sized case headspace (head to shoulder reference) inside a 2 thousandths spread. I use a 60-40 mix of STP (engine oil treatment) and Hoppe's No. 9 (bore cleaner) for case lube on a foam liner in a coffee can rolling in a Thumblers Tumbler. Roll on and sprayed lubes gave too much case headspace spread

Powder's weighed to about 1/10th grain spread for long range. For use at 300 yards or less; metering directly into cases with a 3/10ths grain spread is good enough.

'Tis a waste of time (in my tests) to sort bullets by anything except balance; nothing's out there to do that. Buy good ones and just shoot 'em.

As long as bullet runout on loaded 30 caliber rounds is 3 thousandths max, shoot them. 99% are; those that ain't are marked with the high point on the case head and indexed at high noon when chambered.

Trim cases back to starting point after they've grown 10 thousandths; usually 8 to 10 reloads.

August 30, 2012, 08:54 AM	#10
Bart B. Senior Member Join Date: February 15, 2009 Posts: 8,927	I trim new brass to 10 thousandths less that SAAMI spec and uniform the case mouth. Then chamfer mouths with a No. 5 Easy Out which makes a much better angle that standard deburring tools. Then run a bore brush in a drill in and out to slighty radius the inside sharp edge so no bullet jacket metal gets scraped off when they're seated. Turn necks if they've got more than 1 thousandths spread in thickness. No other brass prep I've tried makes any difference getting 3/4 moa accuracy at 1000 in my match rifles. Full length sizing dies are all I use, but I keep sized case headspace (head to shoulder reference) inside a 2 thousandths spread. I use a 60-40 mix of STP (engine oil treatment) and Hoppe's No. 9 (bore cleaner) for case lube on a foam liner in a coffee can rolling in a Thumblers Tumbler. Roll on and sprayed lubes gave too much case headspace spread Powder's weighed to about 1/10th grain spread for long range. For use at 300 yards or less; metering directly into cases with a 3/10ths grain spread is good enough. 'Tis a waste of time (in my tests) to sort bullets by anything except balance; nothing's out there to do that. Buy good ones and just shoot 'em. As long as bullet runout on loaded 30 caliber rounds is 3 thousandths max, shoot them. 99% are; those that ain't are marked with the high point on the case head and indexed at high noon when chambered. Trim cases back to starting point after they've grown 10 thousandths; usually 8 to 10 reloads. Last edited by Bart B.; August 30, 2012 at 09:03 AM.