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

Well JMC, I would be considering a law suit against a gunsmith that deepened chambers without express instruction to do so. It ads no benefit, I mean zero, and it removes metal from the most critical area of the barrel. It won't cause harm if the barrel wall was thick enough but no way of knowing that unless it is measured. Getting an accurate measurement right at the end of the forcing cone and just beyond it so as to know exactly how much metal you have to work with is a lot harder than just running a reamer, which any fool can do. Remember that the walls of the chambers on the side that adjoins the other barrel can't be measured. That's a judgment call made by guess work. I can't believe how often people do it, even reputable gunsmiths, without any mention of reproof. I don't think that any reputable British gunsmith would do it without reproof.

I have shot 2 to 3.5" shells and a big ole tom turkey doesn't know the difference when he gets smacked in the head I promise

I can't begin to imagine how many early American doubles with original short chambers have been reamed to 2 3/4". I don't think removing 3/16" of metal at a very, very shallow angle or degree at the front of the chamber is going to hurt anything on a set L C Smith fluid steel barrels. It will slightly reduce recoil and maybe improve patterns a wee bit. Just shoot reasonable loads and you will be fine. No regrets.
JR

Timely topic because two days ago I picked up a 1929 FW-16 that had its chamber lengthened to 2 3/4". I just figured I'd hold it to 1 oz. loads on birds and my usual 7/8 oz. target loads.

Like Stallones, I have done it to a few guns early in my SxS days. Learned better and wish I had not. Live and learn (and hopefully keep all my fingers and eyes).

Lots of good info and perspectives! I rembember the first time I shot my Ithaca NID 16 with 1 1/8 oz of lead and the recoil sucked. I am not overly concerned about stretching the chambers 3/16" as I have no reason to overload... Mr. Roberts has expressed what I understand to be the general consensus pertaining to L.C. Smith fluid steel barrels and I'm comfortable with that. No I'll will or lawsuits but you will have the barrel walls accurately measured at some point so if I ever part with it, the next owner will know where things stand.

-Jerry

No. You live in Virginia so they can just drop a pallet of shells at your doorstep w/o getting a signature for delivery from you. Consider yourself lucky some poor fella from Kalifornistan was asking us at another forum about shipping costs for 55 flats of shells. Apparently real soon ammunition will not be able to be delivered to his doorstep.
Governor election is just around the corner be sure to vote.

Per Sherman Bell's research on long hulls in shorter chambers, simply lengthening the forcing cone without lengthening the chamber will negate much of the pressure increase (which is typically less than 1,000 psi) resulting from the slightly longer hull.

I have a modern British 16ga (Webley & Scott 700) with 2 1/2" chambers. The chambers are factory, but it's obvious that someone had the cones lengthened. I shoot 2 3/4" shells, reloaded to low pressure and with 7/8 oz shot, in that gun. They work well. For heavier hunting loads--and I won't go any heavier than 1 oz anyway--I'll use RST's.

Sorry about the unwarranted chamber work on your Elsie. As others have said it's an old storry and probably no harm done. If you had this helpful video, you could have saved some cash!

https://www.youtube.com/watch?v=amBveFBnVgY

It's nice of you to try to make the OP feel better and I'm sure you are probably right, at least I hope so. Still some issues here though. What you describe is just lengthening the forcing cones not deepening the chamber. No comparison. Reducing recoil? Laws of physics say otherwise. Better patterns? Where is the evidence for this? Sherman Bell's experiments on this subject were very informative but he never mentioned the added strength the shell casing provides to the chamber wall. Not at all negible and where it extends into the forcing cone will also add it's pressure resisting strength to that area.
Any increase in pressure caused by the constriction of the case mouth will be mitigated by the added wall strength.
My main complaint is still the same. People reaming deeper chambers without first measuring and profiling the barrels. In a country with no proof laws. Jesus wept.