[Big Lou]

So a little back story. I’ve been playing around with a semi custom 6mm AI I had built several years ago. I didn’t even get to really shooting the thing for probably two years after completion. Shameful. I know.

Anywho, I’ve been primarily using Remington brass to fire form and I’m nearing the end of my rope on trying to make it work and last. It just isn’t very good stuff for such application. The small quantity of Norma 6mm I acquired was really good but good luck finding it. I got my hands on a limited quantity of Norma 7x57 brass and formed it all down to 6mm and fire formed. It’s proved to be very good. I’m having some difficulty finding more new product but I have located a decent quantity of Lapua 8x57 and thought it might be worthwhile going through the process of making what I need out of it.

I was thinking I could go through my established process using 7x57 but add in one extra step being to neck down 8mm to 7mm before hitting it with a FL 243 Win die with no expander. Then a FL 6mm with no expander sizing down until I get the crush fit required when chambering in the rifle for proper head space. I have skipped the 243 portion before but sizing required a lot more effort than giving the cases that little 20 degree taper to start the 6mm portion. Expand up for neck turning after that. This chamber is a standard 0.276” neck so with the turning, I can essentially end up with case necks turned down just enough to replicate having a no turn neck type dimension. Not to mention much better brass quality. I’m using a bushing die for sizing my fire formed cases so changing up neck thickness on brass can be easily compensated for with a bushing swap.

Anyway, just thought I’d put out a feeler for feed back before I dropped the cake on the brass. I can’t say how much I like this cartridge but for anyone considering; to have good brass, I really don’t know if I’d do this one again when the barrel is toast.