I think gas sealing was always the reason for 1/8" shorter chambers. I don't think that better patterns were ever a part of the equation. Pete, I don't disagree that lengthening chambers is a benign act on a less than collectable gun. However, no one can argue that it doesn't cost money, and doesn't sometimes lower the price of a gun when offered to a serious collector. I would rather have the extra steel in the area of the forcing cone than a couple of hundred pound feet of pressure. The very small rise in pressure has been proven empirically, the cost of drilling out barrels and the related shipping expense doesn't need to be proven. It is there.

Hi Bill, not trying to argue just asking food for thought questions.

What about my other questions? Especially did Parker change to 2 3/4" 12 ga and if so when? Did Parker or Remington at any time ever lengthen or recommend lengthening chambers? Is there any documentation?

What does Turnbull, DelGrego, Kearcher etc. recommend today?

2 5/8" to 2 3/4" is not much of a jump but 2 1/2" to 2 3/4" is at least in my mind.

If Parker had survived into the modern times would they recommend leaving chambers alone of bring them to SAAMI standards (even if it was just for liability reasons)?

Seems to me we have a gamut of high condition orginal high grade guns to solid but very worn knockabouts. Altering a museum quality firearm is probably not a good idea. Lengthening chambers and forcing cones could be a good choice on a low grade shooter where performance matters more than collectibility

Shotguns have evolved and knowledge of how they perform has improved. I believe it is a given today that shotgun performance is improved through back boring, long forcing cones and chambers sized to current shells.

I have wondered if P Brothers thought it would be easier, cheaper and less trouble to market 2 5/8" chambers for 2 3/4" shells than to retool and consider modifying all existing guns to meet the changes occuring in the early part of the 20th century.

The cost of lengthening chambers is there but it is not significant to what the average price of gun is including Trojans.

Just my .02 Pete

CHE 241,601 12ga is marked "For 2 3/4" shells". The chambers measure 2 5/8" to the beginning of the forcing cone.

The Remington era specification sheets for their Parker guns are reproduced on pages 164 to 169 of The Parker Story and show the chambers 1/8 inch shorter then the intended shell. A.P. Curtis did a couple of articles in The American Rifleman (July 1936 and March 1938) on the virtue of short chambers.

Pete, my Mahoney girl is 7 1/2 and is at the height of her powers. She is a bird machine. Currently her daughter is pregnant and I'm first in line for a puppy.

The A.P. Curtis articles that Dave mentions are the articles that I alluded to earlier in this thread. The Remington specifications that Dave mentions were dated as late as February 20, 1940, so, obviously, Remington kept the short chamber specifications to the end of production. Notice the marking on late Remington guns says "For 2 3/4" Shells" with no mention of chamber length. The chambers for 28 gauge and .410 bore guns were 1/16" shorter than the shells intended to be used.

Austin, I think you will find the "theory" of short shells in slightly longer chambers in the Curtis articles. I haven't read them for a while, but I think you will find that the "theory" involves gas rather than pattern. On the other hand, in the 1916 article I mentioned earlier, Askins mentions the 80% patterns that were shot in Edwin Hedderly's little gun. I thought he was referring to a 20, but later I see that Hedderly claims 80% patterns in his 16. Now, 94 years later, we find that Hedderly's smallbores were chambered very short, 2 3/8" in the 20 and 2 1/2" in the 16 as I recall.