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3-inch shells, 2 3/4 in chamber

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26 December 2008, 01:25
audsley
3-inch shells, 2 3/4 in chamber
This isn't really a reloading question, but I figure the people who hang out here will most likely know the anser.

Recently I bought a used (mfg circa 1958) AYA Matador side-by-side with 2 3/4 in chambers. A couple of days ago I picked up some Bismuth shells thinking I'd try for ducks if I came across any. After I got into the field I noticed the shells were 3-inch. Shell length is something I should have remembered to check before buying, but I didn't. What surprised me was the 3-inch shells seemed to chamber just fine in my 2 3/4 inch chambers. What would have happened if I'd fired one? Does that fact that it chambered 3-inch shells indicate that a previous owner had the chamber enlarged and no one bothered to tell me or have the barrel re-stamped?
26 December 2008, 02:09
mete
DON'T DO IT !!! It's not a problem of chambering but what happens when you fire it. In a 2 3/4" chamber with a 2 3/4" shell the end of the shell opens flat against the chamber.A 3" shell in a 2 3/4" chamber the end of the shell can't open all the way [ no room for it ] and excessive pressures develop !!!
I would also not use anything but lead shot in a 1958 gun as the barrels were softer.That especially goes for steel shot !! coffee
26 December 2008, 07:11
jb
When I was a teen,we had a spanish .410 side by side with,I found out years later,2 1/2 "chambers.(It was marked in metric)
There were no 2 1/2",410 shells stocked in any of the stores we bought ammo.Didnt even know such a thing existed.
I must have fired thousands of 3" shells in that gun.
My brother still has it,it didnt damage it.How,I have no idea.


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26 December 2008, 10:31
303Guy
Perhaps this thread should have gone onto "Gun Smithing". Still, what I have been told (by a shot gunner/gunsmith) is that shotgun chambers are cut for star crimp type cartridges. If one were to use roll crimp cartridges there would be no problem as the roll can unfold in the 'shorter' chamber. This may be why the 410 survived. (Also, a 410 can withstand higher pressure due to it's being smaller - but don't push it just because I said so ... ALWAYS DOUBLE CHECK WHAT YOU HEAR! Roll Eyes) You can easily check your chamber length. Make up a wooden dummy the length of an unfolded case and see if it fits. Allow some reasonable clearance. Again - double check!

The leade or taper in from of the chamber is there to direct the shot into the bore like a nozzle or venturi. Apparently, the pressure rise due to the star crimp unfolding into the leade can destroy a gun quite quickly!


Regards
303Guy
18 January 2009, 00:51
shorthair
DO NOT ATTEMPT IT thats too fine a gun & your too fond of your fingers & eyes ti risk losing them both over a error of this size.
19 January 2009, 23:14
cgbach
I can't remember the issue but this was covered in the Double Gun Journal within the last year or so, with pressure data. Very interesting; it will surprise some of the people here.
C.G.B.
24 January 2009, 06:54
vapodog
a kid I was duck hunting with in North Dakota shot 3" shells in his J C Higgens 2 3/4" pump.....had trouble ejecting them was all as the casings were too long for the ejection port...but FWIW I'd sure not recommend this to anyone!


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27 January 2009, 07:33
craigster
quote:
Originally posted by vapodog:
a kid I was duck hunting with in North Dakota shot 3" shells in his J C Higgens 2 3/4" pump.....had trouble ejecting them was all as the casings were too long for the ejection port...but FWIW I'd sure not recommend this to anyone!


My best friend in HS had the same gun and did the same thing, the gun was as loose as the gooses and ducks we shot at. The gun never had time to hurt him, he was killed in Viet Nam.
28 January 2009, 02:09
swampshooter
On a duck hunt several years ago i had gun problems and a friend loaned me a ww #21 duck gun. a very fine, expensive gun. He said my shells would be fine. This gun was out of my price range for a hunting gun and i was not familiar with it. I continued to hunt the rest of the morning with my 3" bismuth, this kicked the snot out of me, and looking over the gun noticed that it was a 2 3/4" chamber. From the recoil generated I CAN SAY WE WERE LUCKY THIS GUN DIDN'T COME APART. Pressures had to be extremely high. My suggestion is don't do it.


velocity is like a new car, always losing value.
BC is like diamonds, holding value forever.
31 January 2009, 13:16
BBBruce
Any advice on using steel shot in a 1968 side x side 12 gauge Stevens?
04 February 2009, 04:44
Joe Hunter
Shotgun chamber length is based on the shell/hull length after the shot has been fired and the crimp is unfolded. So yes, a 3" shell will fit in a 2 3/4" chamber because the 3" shell is about 1/4" shorter due to the crimp fold.

Do not shoot shells longer than indicated on the barrel!!! This can and will cause high chamber pressures since the crimp and load will jam in the forcing cone. The fact that some have gotten away with it doesn't mean the next shot will not exceed the pressure limits of the barrel/chamber in question.

This is why manufactures proof test there barrels at much high pressures than Max. Aver. Pressure, but it is no to be taken lightly.

Be safe and good luck.
08 February 2009, 09:25
GSSP
I'm going to be a semi desenting voice of reason. Pressure is what you have to careful of. If you're shooting factory 12K psi load, then, "no" don't shoot them in the shorter chamber. If you put up lower pressure loads or bought loads which you "know" to be about 7500 psi or less than it is safe. This was reserched quite extensively over on either gunshop.com or shootingsportsman.com about 5+ years ago. I shoot a 1896 Birmingham built Webley & Scott Screw Grip BLE, retailed by Manton of London. I shoot 2-3/4" AA hulls in it's 2-1/2" chambers all the time as my practice load. My pressures are sub 7k psi. This is a very light (6 lb 2 oz) and delicate gun and it's tight as ever.

Alan


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18 February 2009, 06:47
LE270
quote:
Originally posted by mete:

DON'T DO IT !!!


I second that advice.


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