Avenger
Veteran Member
Update: I took those mystery 6mm cartridge cases and attempted to resize them to 308, but I couldnt move the shoulder back. The press would cam over before moving the shoulder all the way. So I annealed them.
I used a once fired 308 unsized cartridge case to zero my calipers.
I ran the 6mm brass through my die after lubing inside the case mouth with paste lube.
I got the shoulder to bump back .0015"
Here is progression. On the right is annealed 6mm (looks burnt because of the case lube), middle is the 6mm resized, and the once fired 308. Using my eyeballs, it looks like the shoulder needs to come down more. But the datum line is right in the correct spot. My LE Wilson gauge says they will chamber.
Only had one 'oops.' The case split while necking it out. This is probably because the wheel on my annealer started to slip. I noticed it on the last piece, which is probably this one. Too soft on one side.
Now I just need to trim them to length. I'll do that out in the shop with the drill press and the RCBS 3-way cutter. That way the brass mess will be out there. Thats quite a bit of brass to trim down.
These are extras, and probably wont be used for anything other than plinking or barrel break in processes. It may be a while before I even load them. I got to load up several 6.5C for Boomershoot! coming up. Time to start working on those.
I used a once fired 308 unsized cartridge case to zero my calipers.
I ran the 6mm brass through my die after lubing inside the case mouth with paste lube.
I got the shoulder to bump back .0015"
Here is progression. On the right is annealed 6mm (looks burnt because of the case lube), middle is the 6mm resized, and the once fired 308. Using my eyeballs, it looks like the shoulder needs to come down more. But the datum line is right in the correct spot. My LE Wilson gauge says they will chamber.
Only had one 'oops.' The case split while necking it out. This is probably because the wheel on my annealer started to slip. I noticed it on the last piece, which is probably this one. Too soft on one side.
Now I just need to trim them to length. I'll do that out in the shop with the drill press and the RCBS 3-way cutter. That way the brass mess will be out there. Thats quite a bit of brass to trim down.
These are extras, and probably wont be used for anything other than plinking or barrel break in processes. It may be a while before I even load them. I got to load up several 6.5C for Boomershoot! coming up. Time to start working on those.
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