16 Ga 2 3/4 chambers and barrel min thickness

[brushbuster]

Hello all,

I have a 16 Ga Sterly Philly gun that at some point went back to the factory and was rechambered to 2 3/4 and so stamped. I had Hosford measure the barrels and the minimum wall thickness was .030 and .039. Those seem pretty respectable to me based upon what I’be been able to read. Would you be concerned about using reasonable 2 3/4 loads out of this gun?

The same gun also has a 20 Ga barrel set with 2 3/4 chambers (not factory stamped) with minimum wall thickness of .035 and .041 which again seem reasonably thick to me. Same question would you have any concerns with reasonable 2 3/4 loads in the 20 Ga set?


Here are the 16 Ga loads I was thinking of using.

[Stan Hillis]

In my humble opinion your choice of load as pictured would not concern me, to use in your gun. I use similar loads, in my 2 3/4" chambered Fox guns, regularly.

But, only you can make that decision, based on your knowledge of the particular gun.

[vaturkey]

Those are plenty thick IMO. There are many original Foxes with 4 weight barrels that are unmessed with and they are often found at less the .030 MBWT.

[brushbuster]

Thanks Tom and Stan appreciate you weighing in.

[Silvers]

"Minimum barrel wall thickness" numbers are assumed to be at the choke leades and if so the numbers stated by the OP earlier are typical for all but the lightest profile Fox barrels.

The more critical numbers when Fox chambers are lengthened are the thickness measurements in the high pressure zone just ahead of the new chambers. That's especially so for early Fox 20-gauge chambers that were cut ~ 2-3/8" and even as short as 2-1-4” (as measured) for period 2-1/2" shells, and I've also measured Fox 16-gauge chambers that were pretty short. Let's remember that when asked to lengthen, Savage/Fox checked the barrels no matter what gauge for internal flaws with a period X ray technique and then reproofed at the gun owner's risk and if passed the barrel flats were stamped with the Utica proof stamp I call the SP/Oval. Gunsmiths doing rechambering nowadays usually don't have the means to do magnafluxing or similar nor have access to SAAMI spec proof loads; and indeed I've measured Fox barrels with chambers that were lengthened excessively probably by inattention or just to make sure, also those with so-called long forcing cones that while OK in modern high tensile alloy steel barrels are questionable in vintage Fox and other maker's mild steel barrels. My word of advice is to use very mild pressure loads in such barrels and also to somehow positively mark the barrels so someone doesn't get in trouble in the future. That can be done with a paint pen without permanently imprinting the barrels.

Sometimes you can get away with things for a while. Let me relate my story about the mine mule that the miner hit on the head with a shovel every morning just to show who was boss. That went on for a long time then one day after the shovel hit the mule kicked the miner in the groin, knocked him over and caused shall I say a bad injury. When asked what happened afterwards the miner said: "gee he never did that before". frank

[brushbuster]

Thank you Frank for the information much appreciated!

I double checked the 16 Ga Philly barrel set which was restamped “16 Ga. - 2 3/4 Chamber” and indeed I do see the SP oval stamp so that all seems to line up.

The 20 Ga set is a bit of a mystery. Just to be safe I’m sending the gun in for a strip and clean and have them check the thickness ahead of the chamber and also check the rotary bolt lock up before I try any reasonable 2 3/4 loads in it.

The alternative, I’ve been saving all my 20 Ga and 16 Ga RST hulls and at some point would like to start to reloading them myself with some low pressure recipes. I plan to order the Mec kits to convert my 600 Jr to 2.5 inch.

Thanks again for the information!
Dennis

[limapapa]

Frank is right about the critical measurement being right in front of the chamber. I've seen American guns with as little as .077 wall thickness at 3" from the breech, but most go .100 or even substantially over. My personal preference is for at least .095, but I have no empirical evidence to support that. Just got to go with your gut. I have no problem with thicknesses in the .020-.030 range out near the muzzle. Just that the thinner you go, dents are more likely.

[Silvers]

.020” is marginal ime at the choke leade. I once had a desirable 32” Fox Krupp barrel ruined by a hacker “gunsmith” in New England who overhoned it (for pits) beyond what I’d specified and the finished thickness was only .018”.019” at the leades. 50 shots each barrel with regular factory Gun Club 1-ounce loads bulged both chokes. Then another somewhat noted 'smith assured me he could sleeve it but after sitting in his shop for about 1-1/2 years he declined and said he couldn't find 32" tubes. I think about that barrel often; after I retrieved it I was disgusted and tossed the barrel into the neighbor’s farm pond across the road. But as it turned out a small miracle happened and all became well with that Fox. Long story best told while sipping spirits. . frank

[Stan Hillis]

I would love to hear that story one day, over three fingers.