Ga-Rand Mystery

[Dave P]

So i was shooting a garand match today. Fed cases, CCI prmr, 46.5 gr imr 4895, Nos 168's. Cases have been used 3-4 times; trimmed to length.

After firing tho, about 1/3 of the cases measure ~.33 neck, vs the norm of ~.34". Can't find anything weird with the cases otherwise. Checked length, weight, dia.

Why would some not expand to the chamber neck width?

Tanks
Dave

 

[PaulS]

Dave P.,
Some of the cases could be hardening more quickly than the others. Have you annealed the cases? Are the necks all the same thickness? I am sure that the other folks here will come up with more than I but these would be the first steps I would make in checking for problems. (Will a bullet slide into the cases with the smaller diameter necks?)

PaulS

 

[Dave P]

Yeah Paul, that was what I was thinking too. Necks getting work hardened - but this seems extreme.

No, I have not annealed them; might do that, or just trash em.

And no, the bullets do not slip back into the fired cases (the smaller ones).

Thanks