Originally Posted by lloydsmale
i just did a 100 yesterday. Nothing but standard rcbs 7stw sizing die and hornady oneshot sprayed on the cases like any other time i size. Never had a single one get ruined. Loaded up 50 of them and the bullets seated just like in factory 7stw cases ive got so id bet the necks arent even in need of trimming. All rounds ran though the gun perfectly too.
This threads old now but let me try to get a little more info if anyone still hanging around on this thread.
I just got a 7 STW, and 40 rounds from the builder, problem is the ammo was destroyed in shipping. He's sending more but 40 rounds won't last long. I bought some 8mm mag brass to neck down. I've tried a couple with Rcbs FL die. It necked down well, and concentric, no expander ball. It leaves a donut at the neck shoulder junction. Should I fire form with reduced loads, or can I shoot these cases at full power with good results. The load development is already done, and have load data.
I've heard both here, and still not sure what my best option would be.
I'd appreciate some more direction.