Cannelure Affect on Accuracy

[rcmodel]

+1

Try to pull a 55 grain bullet without a crimp and proper case neck tension with an impact bullet puller and get back to me.

rc

 

[steve4102]

Steve: If the bullet in an AR cartridge moved that much just from being chambered I wonder how the .30-06 bullet is moved in a cartridge fired from a Garand? I am pretty sure the forces and mass of the M-1 in operation far exceed those in the .223 round in an AR, but then I am not a scientist, just a recreational shooter.

Good point. If you have a Garand do a similar test and report back.

I have a 7.62 x 39 Mini-30, 30-06 BAR, 300WSM BAR, AR-15 in 6.5 Grendel and of course AR-15 in 5.56. I have done similar tests on all of these actions and cartridges. IMO if anyone thinks their 180gr 30 cal bullet stays secure in a BAR or similar, with nothing but "neck" tension, they are either very luck or totally unaware.

OH, and by neck tension I mean up to and including .006 neck tension, (Bushing Dies).

 

[bluetopper]

That earlier post stating that bullets have rifling marks/indentations on them when they leave the barrel is very true and made a light bulb go off in my head.