6.5 Grendel 100gr Wolf Projectile Diameter

[depletedyourcranium]

I know there was a rumor that Wolf was upsizing their tooling to make the 100gr projectile a 0.264 diameter over the previous 0.262 diameter. I just measured some new production I got in today with a production date of 9/2020, and the pulled bullet still measured 0.262. Just a heads up to anyone who's been curious and hasn't been able to snag any new production ammo.

Personally, I don't think a change is warranted because its just as possible to hurt accuracy as much as help it but that's another discussion entirely... Regardless, it looks as if those changes are either unfounded rumors or still have yet to be implemented.

[biodsl]

Thanks for the info. Good to know.

[VASCAR2]

[Fess]

It would make perfect sense for bimetal bullets to be slightly undersized. I remember reading an NDIA paper a number of years ago that tried to quantify the forces on a bullet as it enters the rifling and travels down the barrel. If a bullet is the same diameter as the barrel's grooves, its cross-sectional area is greater than that of the barrel which has lands protruding into it. In other words, the bullet must be swaged to a smaller average diameter. The jacket must become longer. The steel in a bimetal bullet is less ductile than brass or copper, so it would make sense to size it closer to the actual cross-sectional area of the barrel.

I slugged a Russian Saiga 7.62x39 barrel. The lands were much more narrow than the grooves, resulting in a greater cross-sectional area in the barrel and less distortion to the bullet. Also, the diameter of the Russian and East European 7.62x39 bullets tended to be 1 or 2 thousands smaller than the grooves of that Russian Saiga barrel. Early in the life of the Grendel, I recall that Bill Alexander stated something about bimetal bullets preferring the sharp "European" rifling to what most US barrels used. I've always wondered what he meant by that.

[LRRPF52]