I have a strange question about reloading for the "shorter" 10 gauge.

My friend has an old 10 gauge that takes the shorter 10 gauge shells. I think they are 2 and 7/8". He reloads and has for several years, the black powder shells. However, he has heard about some people reloading for the shorter 10 gauge, using the plastic hulls. Something about cutting them to new length, then heating the hull with a curling iron, then crimping. I don't know if they are fold crimping or roll crimping.

Anybody out there know anything about this??? Any help would be greatly appreciated.

Thank you.