Lengthen chambers to 2 3/4" ??

[Bill Murphy]

"Taper the chambers" refers to taking some metal out of the chamber ahead of the extreme front of the chamber at a bit of a taper, rather than starting the cut at the chamber mouth. It's a good theory, but doesn't do much to lower pressures. I don't measure my chambers and haven't for sixty years of shooting and buying shotguns. I use light loads in light shotguns and that seems to have eliminated any problems. When I bought my PHE 12 gauge trap gun, I used it as a pigeon gun, as have the previous owners, for roughly a century. I am sure that this gun has never shot many shells with less than 1 1/4 ounces of shot, because its previous owner was a competitive pigeon shooter and I have used this gun for a similar purpose. I have never measured the chambers, but I'm sure they are 2 5/8" or shorter as was specified in the stock book. It was proofed at PB with 1 1/4 ounces as I recall, but I'm not sure of the 2 5/8 and 1 1/4 ounces. I'll report back. I shot 50 rounds through it yesterday, and it is still undamaged.

[Drew Hause]

I still don't understand. Chambers were designed with a taper; 12g from .811" to .797". Removing metal would be increasing the diameter of the chamber, which if done toward the forcing cone would decrease the taper, and increase the angle of the cone if not lengthened.

[mobirdhunter]

Back in my (even more) naive days, I followed the gun writers of the day (about 35 years ago) and their recommendation to lengthen the chambers from 2 1/2" to 2/3/4" and lengthen the forcing cones. I sent a pristine, original Fox AE 16 to Griffen and Howe. They said that in their judgement the chambers could be lengthened, but there was insufficient wall thickness to relieve the forcing cones. Thank goodness for a professional to do the work, but I still regret lengthening the chambers those many years ago. Lesson learned.

I left another Fox CE with a dealer (same timeframe as the gun above) who said he'd get the chambers lengthened to 2 3/4." When I got it back, the chambers had been cut to 3 inches. According to the smith, he did so to "keep some dummy from sticking 3 inch shells in the gun." Another lesson learned (and I'm still wondering if I was the dummy or the gunsmith...or both of us).

[todd allen]

Originally Posted by Bill Murphy

"Taper the chambers" refers to taking some metal out of the chamber ahead of the extreme front of the chamber at a bit of a taper, rather than starting the cut at the chamber mouth.

I think this is a good summary. I don't know if the procedure made any difference, but it's a done deal. Along with choke tubes, which in retrospect, I wish I had not done.
BTW, my background is similar, though I'm a few years behind you, at 68 years.
Box birds were the game, and I was typically shooting them somewhere once a week, for about 30 years.
I had virtually quit shooting about 2008, except for a little upland bird shooting here and there.