[Lawyerman]

Has anyone ever done this? The 3 incher should chamber because the smaller chamber has to be big enough to allow the round to "grow" when it is fired and the crimp expands. I would never advocate doing this but has anyone done it by accident? What happened? I would assume it fired and then you couldn't get it out tying up the gun. That's why all my guns are Magnums!

[Rat-30]

In a modern, late model shotgun w/o 3" chamber,
Firing 3 inch in a 2-3/4 chamber will result in higher than standard pressure as the shot charge pushes past the crimp that's opening into the forcing cone, resulting in harsher recoil and extra stress to the action of the shotgun. Pain to the shooter. Lots of it. And, yes, the case(s) was/were hard to extract. (Not that I would be so silly as to do something like that, twice, you understand, it was, a, uh, Friend. Really)

Older, well-made shotguns will wear at a much more accelerated rate, perhaps failing (thankfully, my friend has no experience with this phenomenon).

Older, less-well-made shotguns are not to be considered - let me be plain:

Shooting 3-inch in a 2-3/4 chamber is not desirable and in most all cases, not safe over time (how much time is debatable-I wouldn't want to gamble that it's later vs. sooner).

Best,

[Omaha-BeenGlockin]

Kb!!!!!!!!!

[Coronach]

It functions fine, with the exception of ejection. The empty shell is a bit too long and if you do not rack the action vigorously, it will hang up on the ejection port. I probably did this with 20-50 rounds, and the gun shows no signs of any problems, whatsoever.

That said, I do NOT recommend doing it. I did it accidentally back when I was young and stupid and hadn't yet learned to be careful about what I was doing.

In a SHTF scenario, however, it would seem to function well enough. If all I had was a 2 3/4" gun and 3" shells, I'd load them up and bang away. In any situation less dire, I'd use the right shells for the gun.

Mike

[foghornl]

Small "owwie" when doing this.

GREAT BIG "OWWIEEE" when the barrel lets go....

Not real high up on the list of good ideas.

[Lawyerman]

My thoughts were as coronach stated, say you run out of 2 3/4 and what you scrounge is 3" and someone is shooting at you? Run the gun with what you got!

[Jim Watson]

Anybody got some back numbers of the Double Gun Journal? As I recall, it had an article about long shells in short chambers, like 2 3/4" in 2 9/16" guns. They had pressure tests and all, and saw much less difference than the usual alarum. But that was less lenghth difference and lighter loads than a 3" magnum in a 2 3/4" field gun.

Like the man says, if that was all I had to fight with or was hunting subsistence food, I'd shoot them. But no reason to go looking for trouble at home.

[BMWGuru]

One of my hunting buddies took his first whitetail many moons ago with a couple of 3" slugs in a 2 3/4" 870. He had to knock the second shell casing out with a cleaning rod. He hasn't attempted this since then as far as I know.

[mod12]

my father had an original mod 12, 20 ga, with a 2 9/16 " chamber. i bought standard length shells not realizing what i was doing. after firing about a half dozen and getting a mouse under my right eye, having ejection problems {the claw would tear thru the brass shell rim leaving the fired shell in the chamber} i took it to daves' gun store in Cols. Oh.to find the problem. they lengthened the chamber. this was about 1951. it still runs fine

[Mike Irwin]

I've seen two older (WW I era) single barreled shotguns with SEVERELY bulged barrels from this happening, and a third, a pre 1920s double barrel, with a ruptured barrel.

All 3 were fluid steel, not damascus, but all three were foreign imports, probably Belgian.

[Gila Jorge]

Back 30 years ago, I had a Winchester 101 12ga with 2.75 chambers opened
up to 3 inch chambers by a local gunsmith. Used it for years on ducks
as the 28 inch barrel was about perfect back then. Would NOT think of shooting 3 inchers in a shorter chamber though. Fond of my hide and my guns.

[TrapperReady]

First of all... not something I would recommend.

However, I read an article in "The Double Gun Journal" where the author conducted a series of experiments to see exactly what the increase in pressures would be.

As I recall, they were measurable, but shouldn't be catastrophic in an otherwise sound gun. I'll look around and see if I can dig up the article and post some of the findings. IIRC, he was looking more specifically at using 2 3/4" shells in a barrel designed for 2 1/2", but he also used a 3" as well. There was also some discussion of the effect on pressures with respect to short or long forcing cones.

The only time I've seen someone do this in the field was a 3" shell used in an 870 with 2 3/4" chambers. While the first shot went off just fine (and there was no damage to the gun), it was unable to eject the spent shell, and we had to pull it out manually.