Larry,
There were many 16 ga. Browning A5s that were barrel stamped 2 9/16". And most all were lengthened to 2 3/4" by gunsmiths in the 1960's.
I also have a whole box of 2 9/16" 16 ga. shells from that era.
SRH
Good point, Stan--although those are foreign-made (Belgian) guns on which you can find a lot of information in the proofmarks that you won't find on American guns.
I'm not an autoloader guy, although I've owned 3 16ga A-5s: a Standard and 2 Sweeties. But all were factory 2 3/4". Isn't there some other modification that has to be made to those guns, other than just chamber lengthening, before they'll handled 2 3/4" shells? Ejection port issues, maybe??
Re pressure, Curtis states in his articles that the then-new, high speed shells "developed approximately 500 pounds greater breech pressure than the corresponding standard 12ga loadings." Note that this was written AFTER the advent of SAAMI (mid-20's), by which time the industry was attempting to get a grip on pressure, velocity, etc via standardization--which didn't exist to the same degree prior to WWI. "Normal 12ga pressure", at the time Curtis was writing (late 30's) is given as 9-10,000 psi (which would actually have been LUP, so more like 10-11,000 psi as measured by transducers).
Last edited by L. Brown; 11/20/14 09:02 AM.
