Thread: 500 BPE load advice

So I have made a barrel block and put the barrel on to the action properly.
Nice fit

Primed a case and it fires just fine.
But the primers back up a bit
The punch works great.

So the rim on the 500 nitro case is 0.9mm think and the rim on an original 500/450 round I have is 1.5mm thick.
So I'm picking that there is 0.5mm of head space there extra due to the very thin nitro case rim.
The breech block to barrel looks good

I could make up a 0.5mm washer up from shim material
Or find a .5mm x clip that would fit into the rim groove
Or see if Bertram makes the same case with the thick rim

All good problems as its nice to put it completely together and make even a small bang because it's been a long long time since this last had a case in it