Finally got around to trying my 358156

[ScottJ]

bought months ago off eBay.

Sort of odd results. The rear two bands in front of the gas check groove and grease groove are around .363 on average but the front two bands where the crimp grooves are measure .355-.356 on average. Guess maybe that's why it was on eBay.

Guess this doesn't really matter since the rear bands are big enough to give me seal and it is a GC design (although I'm thinking of trying them checkless in .38 Special).

My ultimate plan is to have it hollowpointed and run it at magnum velocities over slow powders. Probably with range scrap for the alloy.

[Bass Ackward]

Is this a single cavity by chance?

That small bullet takes a while to really heat up the blocks. And since this is a base pour mold and heat rises, I am not surprised by the dimensions you obtained.

Try running hotter and if necessary, rotate your blocks upside down so that the heat rises to the nose and see if it makes a difference in your dimensions. Then if it does, you'll have to figure out a way to make it work.

[ScottJ]

It is single cav. It did take awhile to heat up to get good fill. But I was running right on the edge of frosting them. Or so it seemed.