Thanks Drew Your hypothesis of causation is the same as mine. Any load from RST, Remington, Winchester, Federal, Fiocci or Rio that could have been placed in the gun would certainly have been less than original proof pressures and likely less than max working pressure.

Honing sure does produce high condition beautiful barrels. Before anybody blames the shooter, the gun needs to be inspected.

With normal wall thickness, the chambers blow with too high a pressure. The barrels past the chambers blow if there's a obstruction. With both barrels bulged in the same place I wouldn't think it's an obstruction, but thin barrels. I fully agree with Bruce and Drew.

+3 for thin walls and most likely lengthened cones. I can't imagine a factory original one frame 16 not having enough meat to digest almost anything. And to happen in both barrels in the same place makes it almost a certainty in my mind.

Steve Barnett is one of the "good guys".

PS: I shoot a lot of damascus guns and consider all to be perfectly safe. However, a few months ago I got stuck with a GH 12 with 28" barrels that upon measuring the walls near the chambers am convinced they would be very dangerous to shoot even low pressure loads. I mean they are scary. Fortunately I have a set of widowed barrels that fit almost perfectly and are off to the smith for final fitting. I hate to destroy the original barrels so am trying to figure out how to mark, plug, or whatever the bad ones so they will never be fired. Any ideas?

The honed barrel theory is a good one...but it's still just a theory until we get some more complete data.

To counter, I'd offer that Steve Barnett would know they were thin and would not have had the gun out for open shoot day.

I doubt we will get any additional data. I don't know if Steve checked the wall thickness prior to purchasing or trading for the gun. IF he knew it was thin the gun would have NEVER been on the table.

Dean, how many of your guns can I borrow?? :rotf:

Joe could those barrels be lined or perhaps shot with sub-gauge inserts?

Honing or lengthened chambers would be the likely cause at that location. I once owned a GHE 12 which developed a bulge in the chamber when I was using a set of chambermates in 28ga. The "o" ring on the insert failed and the pressure was essentially trapped within the chamber. I found out later that the previous owner had lengthened the chambers to 2.75". That was a long time ago, way before I knew anything about barrel modifications.

To answer the question you asked. Minimum proof pressures in Austria for 16 ga. and above is 12,800PSI, for smaller gauges the minimum is 14233PSI. Proof loads manufactured by Remington produce pressures which exceed standard loads by as much as 50% and are clear plastic and marked as proof loads. Remember this when you remove a bulge from a barrel the bulge has already yielded once and removing the bulge forces the metal to yield again. Finally since I value my eyes above all my other senses I test Damascus guns I want to shoot by tying with the top rib against an 80 lbs. truck tire, adding 30 ft. of string to each trigger, lying face down on the ground with a hard hat, and pulling both strings one after the other. Yes I used proof loads and hunted the gun there after.

After thinking about this some more. I've reminded myself of a personal experience I had with a CE grade Fox with 30" cromox fluid steel barrels.

I bought this gun when I was fairly new to older doubles and was still in the make the gun the way I want it to be phase. I didn't like the full & fuller chokes it came out of Philly with, so I sent it out to a well known double gunsmith to have them opened. I stressed that I didn't want them opened if the wall thickness didn't allow the procedure to be done. He supposedly measured them & we agreed to have him do the deed. When I got the gun back I took it out on a hunting trip in eastern Colorado. I forget the exact load I was shooting but they were a typical 6 shot pheasant load. "not one of these high power pheasant loads available today. A bird got up and I missed on the first shot, so I followed up with the second barrel.

My buddy that was with me immediately asked what I was shooting because it sounded funny. I started looking the gun over & found that both barrels had bulged at the lead to the choke tapers. Yes both barrels were bulged in the exact same spot shooting the same ammo! These shots were the first shells fired in the gun after the chokes were opened. Yep it only took one shot per barrel to bulge them.

I sent the gun back to the gunsmith and he immediately took the position that I was shooting too hot a load for the gun and wouldn't stand by his work. When I got the barrels back I had them measured for wall thickness. What we found was the walls at the start of the choke tapers were down to .010" where the bulges started. I've always felt that if I hadn't had the chokes opened that nice set of Fox barrel would still be bringing game to the table today.

I know it's a long story, but one I feel relevant to the theory of lengthened chambers. Live & learn !