.......Maj Burrard and Gough Thomas both reported on the practice of shooting 2 3/4" shells in 2 1/2" chambers, which has been common in Great Britain for some time (provided that the shells in question were made within the pressure parameters appropriate for 2 1/2" guns). And both Burrard and Thomas concluded that the practice was perfectly safe....... Thomas gives the actual pressure figures for a 10-shot string, 2 3/4" Eley Grand Prix shells fired in a 2 1/2" chamber; same in a 2 3/4" chamber. There is no difference in pressure and velocity from one to the other........
Larry,
I have selectively quoted from your previous post to focus the point of my question.
Are ANY of those "2 1/2" inch chambers really 2,50 inches? If 2-piper's post quoting diagrams from Burrard is accurate (that is, Burrard's diagrams are accurate), perhaps NONE of those "2 1/2" inch chambers were 2,50 inches (63,5 mm) but really 2 5/8 inches (67 mm). Firing a true 70 mm hulled shotshell in a 67 mm chamber is quite a bit different than firing it in a 63,5 mm chamber.
It keeps seeming to me that talking about firing 2 3/4 inch shotshells in a perhaps (apparent, even really) non-existent chamber lenght (2 1/2 inches)is really misstating reality, thereby keeping discussions like this one in fantasy land.
Perhaps this discussion might converge IF it were widely understood that expression "2 1/2" inch chambered shotguns and shotshells really means 2 9/16 (16 gauge) or 2 5/8 (12 gauge).
I am still awaiting reportage of shotguns with true 2,50 inch chamber and factory loaded shotshells that are true 2,50 inches long.
But then, maybe 65 mm shotshells in Britian are really 63,5 mm (Eley shotshell box shown in one post) and in Russia 67 mm shotshells are really 70 mm (Geno's post).
Niklas
