Hmm. interesting.
I have my own brass shot shell resize problem.
I got some Magtech brass to shoot BP loads in my James double.
Now these unfired empties just drop right into the chambers of my other guns but are very tight in the chambers of the James.
I think the James must have small diam,minimum chambers & doubt that a sizing die would bring down the size of new brass.
Does any company even make a full length resizing die for 12 gauge brass ?
Or do I need to spin something up myself in the lathe ?
Or hone the chambers ? Don't really like to as plastic shells are a good fit in it now.
O.M