doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com 2 1/2" chambers and 1" cones

2.5" hulls cost the same or less than 2.75" hulls......new, unfired......I don't know where you are getting your information.......I guess you are speaking of off the shelf Walmart specials..(RST-PW).....for those that don't reload....?...

Larry, again you are missing the point..........pressure as read in any reloading manual "IS" using the assumption that the shooter, loader is putting the shell in the proper size chamber......they do not print 'wildcat' shot shell loading data that I know of.....

Major Sir Gerald Burrard commenting on shooting longer hulls in 2 1/2" chambered guns. Volume 2, "The Cartridge", revised edition 1950. Worth a read.

Joe, before I will ask you some question reg. this small piece of cardboard I have to tell you, that in Europe according to CIP 67.5 MM cases is OK for 65 MM chambers. Most Europian cartriges for 65 MM chamber guns loaded in 67.5 MM cases.

Now re. this Parker Bros cardbord. What what I can see,
Length of Shell 2 5/8"
Use Shell 2 3/4"...
I didn't see the length of chamber here.
At the same time cardboard says 'Brass Shells should never be used with nitro powder.'
You'll never insert longer brass shell in short chamber and it means your Parker has 2 3/4" chambers.
So what's your point?

Larry, you said any light load in 2 3/4" shells is OK for 2 1/2" chambers. Now you say every vintage gun has to be inspected. Nice try.

Back to the first question I could give only one suggestion, to send this gun to proof house and to ask those people to proof this gun with proof loads in 2 3/4 shells.
All the rest will up to you, Patriot, and for your own risk. No one official will never tell you your gun with 2 1/2" chambers is OK for 2 3/4" cartriges, light or hot it doesn't matter in this case.

Colonel Charles Askins commenting on "Fitting the Cartridge to the Gun", plus another 10 or so detailed pages on this subject ......"Modern Shotguns and Loads".....1929 - U.S.A. - Chapter 23 - - Worth a Read...!...







JOE:----Your Parker hang tag does not say length of chamber.....is it 2 5/8 for brass or 2 3/4 or 2 1/2 for paper....or just a Parker Typo...?.....Or did Parker just use 'magic' words to describe the "chamber" in 1901 or whenever...?...

Hi, Doug.......

It's my understanding that "Length of Shell" on the hang tag above was meant to be the chamber length. Only thing that makes common sense, especially in 1901 (I know, on special order they'd chamber longer than 2 5/8"--I have one).

Both of these paragraphs are dead on and based on "facts".........

Geno: - 67.5 mm o.k. (2 9/16) but NOT 70 mm (2 3/4)........is that correct Geno...?........

Eley makes 67.5 mm 16's, 12's and 20's........Eley's available UK and on the Continent only now.....they were available in the U.S. about four years ago, through the Eley, Austin, TX dealer........who is now defunct........The Italians make them as well....and the Americans, Spanish, Russians, Dutch, Germans, French, Swiss, etc.......SO, lot's of folks shooting 2.5" guns all around the world.....with the proper size ammo.........interesting........

Correct.

65mm = 2.559" (2 9/16" =2.5625")
67.5mm = 2.6575" (2 5/8"=2.625")(2 21/32=2.65625")
70mm = 2.7559" (2 3/4"=2.750"))
Tatham #7 ran 291/oz so 1 1/8oz = 327 pellets.
Rt bbl was shooting 67% & left bbl 77%, 70%+ patterns are not a modern invention.
DuPont bulk smokeless, which is the powder which would have been used here, no other would have used that wt, weighed appproximately half an equal measure of Black powder. This was then essentially a 3DE-1 1/8oz #7 load (3D BP=82grs). This was "Not" a particularly stout load for a 7lb 9oz 12ga even in 1901.
It is my understanding from both Greener & Burrard that a nominal "2½" British gun has chambers which actually measure 2 9/16" (65mm) or in some cases 2 5/8" (66.67mm) & from Burrard that virtually all fold crimp shells sold after their introduction were loaded in cases longer than the chambers.
I have no idea how old Bell is, but suspect this was well settled prior to his Birth.
I measured a couple of fired US 2 3/4" hulls & they went to about 69mm The two important items for this discussion were both answered by the British work on this which was reported by Burrard in the above post.
#1- The "Loaded Length" of the shell should be shorter than the chamber so the crimp is free to begin opening un-inhibited.
#2- The "Load" inside should be compatible to the guns design.
A nominal 2½" gun with 3 ton proof should never be used with modern Regular SAAMI spec 2 3/4" shells.
"IF Both" of the above criteria are met it really doesn't matter if the actual hull length is 65mm, 67.5mm or 70mm in any gun having a cone length of at least 3/8" (9.5mm). I would never, ever attempt using a longer hull in a gun having a "Step" at end of chamber, but these are very, very seldom encountered.

Note also I do not consider the "Low Recoil" shells as "Regular".

I have read these 4 pages and, well, this is all you have?
There were tonns of papers used up for these themes over here and all stuff was very detailed reseach.

Geno, PA24, and others on the short shell side.....rather than letting all of we long shell shooters have all the fun let's change the debate a little: you who argue to never shoot shells longer than the chambers should provide data and actual research supporting the results you champion.....

It's your turn--let the games begin! Round two begins NOW!