Originally Posted by battue
Originally Posted by jimdgc
I I do know that most 16 gauge shells are not 2 3/4" even if the are marked as such.


Closed and unfired they are not. Fired and open they are. Which is when it counts.


+1

Personally, I wouldn't do it. The additional pressure from trying to iron out the crimp in the forcing cone can change the burn characteristics of the powder and cause higher chamber pressure or an earlier pressure spike.
No need in loosening up the action prematurely.
2 1/2" ammo from Polywad, Gamebore and others should be readily available even with the ammo shortages.

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