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**Unclenick** · December 20, 2009, 09:28 PM

The NRA book Handloading, had an A. A. Abbatiello (sp?) article showing that each thousandth of total indicated runout (TIR) would cause about a half of an moa increase in group size for M72 match ammunition, which was .30-06 with a 173 grain FMJ boattail. The tilt of the bullet in the cartridge remained when it entered the bore. This was true up to about 4 thousandths TIR, beyond which the bullet seemed to straighten itself out from any addition runout by its fit in the bore.

The sliding sleve Forster and Redding Competition seaters both do a good job of reducing the problem.

December 20, 2009, 09:28 PM	#2
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,060	The NRA book Handloading, had an A. A. Abbatiello (sp?) article showing that each thousandth of total indicated runout (TIR) would cause about a half of an moa increase in group size for M72 match ammunition, which was .30-06 with a 173 grain FMJ boattail. The tilt of the bullet in the cartridge remained when it entered the bore. This was true up to about 4 thousandths TIR, beyond which the bullet seemed to straighten itself out from any addition runout by its fit in the bore. The sliding sleve Forster and Redding Competition seaters both do a good job of reducing the problem. __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle