Seating bullet inside shoulder of .308 case?

[44Blam]

I'm slowly moving along with getting setup to shoot cast through my .308 rifle and I made a dummy round and went to chamber it.

My mold is the NOE 311-174-FN-AQ5 and I've sized them to .311.

My barrel slugs to .308.

If this boolit is seated exactly flush with the end of the neck, the COL is 2.77" - which seems just about right. So this is what I went with.

Sadly, this configuration does not chamber as it hits the lands of the barrel and it marked where it hit the lands.

Backing the boolit back into the case about 0.07" allows the round to chamber with about 0.005-0.01" before touching the lands. However, the boolit is now 0.07" inside the shoulder of the case. These boolits are gas checked which basically equates to the GC sticking in past the neck of the case.

This leads to my question. Does seating a boolit slightly past the neck of the case into the shoulder affect accuracy? Eg should I look for a different design to shoot or should I just seat my boolits at 2.70" since it is a very small jump to the start of the rifling?

Thanks!

[454PB]

That's a fairly common problem, and though worrisome, having the gas check below the case shoulder has never been a problem for me.

[dragon813gt]

The 308 has enough neck that this usually doesn’t happen. I routinely have to seat billets below the neck in 300 Savage. I’ve had no issues because if it and I will stop there. There’s a long running debate over this practice. If you can keep the bullet in the neck you’re better off.

[Tackleberry41]

Try a few rounds and see. Plenty of bullets simply have to be seated deep to work.

[243winxb]

I think bore riding bullets should contact and sit on the lands. Diameter of the nose can be cast smaller using less antimony in the alloy. But to soft, not good.

Some size the bore riding nose with a bushing.

[HangFireW8]

In the old, old days, gas checks were slip-on and expected to fall off in flight. So there is a strong tradition of advice against seating below the neck.

Modern Gator, Hornady/Lyman checks crimp on, and (assuming normal cast dimensions) do not fall off at all. Personally I have no fear and seat those loads that require it below the neck. It's your choice.

[popper]

I try to avoid that but the RD in 30/30 Marlin has that problem and I see no detriment.