Anybody putting 70mm ammunition in a 2 1/2" proof stamped shotgun is a fool in my opinion.
Then I'm a fool. Sometimes I use light 2 3/4 case loads in 2 1/2 chamber English guns, because UK chamber dimentions standarts are not so tight as German ones for example. Also it depends on forcing cone length and bore gauge. 12G, 13/1 and 13G are o'key in this case.
I feel I'm pretty much educated to check guns and to choose right ammo for these guns. Sometimes 2 1/2" case doesn't mean at all it could be used in 2 1/2" chambers.
Who says use ONLY 2 1/2 ammo in 2 1/2 chambers probably a fool, because ammo has to be proper to particular gun in many aspects and not only in case legnth.
