doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com Lengthening 2 9/16" chambers

Step away from the cliff, Nial. It's all very minimal.
JR

Yes of course. What was I thinking of?

British guns and their delicate nature. Elsies don't need no stinking proof.
JR

"the added strength the shell casing provides to the chamber wall."

Seriously?

Shirley you jest.

Always missing from the internet discussion boards on this topic, is the part where the original poster is (supposed) to say, "I have spent the better part of the last year patterning my (insert brand name of gun, here) with this (type of ammunition, here) and have discovered a problem, that can't be resolved by using (insert different brand or type of ammunition, here).

Why does it always go this way? At no point was it noted by anyone to start there, to see what he had.

To the OP. if your gun ended up with 2 3/4" chambers by accident, that is too bad, but, not insurmountable. It seems your notions of what to use in the gun, for the shooting you do henceforth are sound. A little testing will go a long ways, I assure you. Patterning guns is about as dull a past time activity as one can come up with, but, one that carries huge dividends, later.

I have had exactly one gun that I couldn't get useful patterns with, at typical ranges I shoot at, with ammunition I had on hand. I honestly believe I would have, but, sold the gun before I did.

Carry on.


Best,
Ted

If you're referring to the R-15 20 gauge....don't feel bad. That thing didn't or just couldn't throw decent patterns no matter what shell was used. I spent a lot of time and money trying to unlock that guns secrets, never could get it figured out.

Shirley I do not jest. You tube has many people who delight in making improvised shotguns. Iron pipe slide firing, plastic flare gun modified to handle shot shells, etc, etc. That stuff is tremendous fun. Scope to try all sorts of ideas and find out stuff for yourself. Make a 12 gauge barrel from a piece of PVC pipe. Reinforce with couplings, then turn down the outside diameter until it blows. Informative fun. Every thousand added to wall thickness has an effect. From ignition to projectile clearing the muzzle the intervening space is just a pressure vessel. People have been fooling with this stuff for ages. You, well maybe not you exactly, could figure out the hoop strength of the shotgun chamber. Then figure out the hoop strength of the shell case and add it to the former. At one time there were people who doubted that the Earth was a sphere.

Dustin,
I suspected that gun was among the first that was produced after Paul Bruchet retired for good. The barrel boring machine at Bruchet/ Darne was 2 stories tall, bored the barrels lengthwise, and was something only a very skilled individual should have been close to. That was Paul.
Hindsight is always 20/20, but, I would have liked to have had someone like Stan Baker look at those bores, and get his input.


Best,
Ted

A Cheddite plastic case measures .025" of work hardened plastic.

It might hold 3 BAR. Let's say it will hold 10 BAR (145 PSI).

At a working pressure of 800 BAR, that is (at the very maximum) a percent and a half.

That's lost in the noise of shell to shell variation.

The Earth is an Oblate Spheroid.

It would be simple enough to test.

Find a rubber plug that fits a shell and drill it for an inflation needle, you know, the kind Tom Brady uses to deflate footballs. Hose clamp to open crimp.

Clamp the thing down so the primer can't blow out, and turn on the air compressor.

If it gets to 30 PSI, I would be shocked.