Tips for Building a SIG SAUER P320 from an 80% JSD Supply MUP 1 Insert (Especially the .45 ACP!) 36
Are you building a SIG P320 from the 80% JSD MUP 1 insert? Do you want to make sure you end up with a quality Fire Control Unit (FCU)? Are you maybe even considering chambering it in .45 ACP, but can’t seem to find any documentation on the “minor modifications” […]
