Anyone have specific information or experience about use of nominal 70 mm hulled shotshells in 67 mm chambers?
We know of CIP permissibility of using CIP 67 mm hulled shotshells in 65 mm chambers. What I have never seen is any specific information about use of actual 70 mm hulled ammo in 67 mm chamber guns. These would seem closely identical situations, given identical chamber pressures.
I am asking because I have a totally original Sauer M2 hammer double with true 67 mm chambers, short forcing cones, tight chokes, etc., typical of various higher quality Germain doubles I have owned. This gun locks up quite tight and patterns nicely with 24 and 28 gram loads in 67 mm ammo (Remington Promo loads and reloads in same 67 mm length hulls). It is my current favorite bird gun.
However, of 16 gauge shotshells readily available in USA stores, only Remington black hulls and USA Fiocchi hulls are 67 mm, even though they are marked "70 mm". Winchester and Federal hulls are 69-70 mm. While I can and do shorten Federal hulls to 67 mm for reloading, I would like to use 70 mm hulled factory ammo on some hunting trips. These would be 28 or 32 gram field loads at 1200-1250 fps, most likely Federal.
Thanks,
Niklas
