doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com Model 12 burst

Yep. Burrard stated that obstructional ring bulges uniformly raise the rib

Steve is spot on regarding bulge repairs. Ribs on or ribs off, swaging even a small amount of metal down is not an easy or pretty task. Regarding shooting a gun with a bulge or a repaired bulge, ask yourself would you feel safe driving a vehicle on a bulged tire? It�s just not worth the risk. I have a small shadow box on the shop wall with a variety of barrel bulges, bird cages, splits, stuck bullets, and blow outs just in case anyone needs additional convincing. Good advice once given by my father, if the report doesn�t sound right or the recoil doesn�t feel right, stop shooting and check your barrel!

Amen brother

Burrard�s Precautions To Avoid Bursts
1. Always buy cartridges from a reliable firm.
Or pay the utmost attention, at every moment while reloading, using the best components in an established recipe. �Close enough� is never �safe enough�:
Julian S. Hatcher, Hatcher's Notebook, 1966
�E.C.� blank powder burns with extreme speed�to give a sharp report when it is not heavily confined. An enthusiast once got hold of some of this powder, being familiar with �E.C.� shotgun powder�and loaded a bunch of shells. To try out his new load he got out his fine Lefever gun, and put up a target in the shooting gallery to get the pattern. There was a terrific detonation, and a big piece was blown out the side of the barrel near the breech, flew across the room and buried itself in a wood bench.

2. Always adopt every possible precaution to prevent different sizes of cartridges being intermixed.
3. Always look through the barrels before starting out on a day�s shooting.
4. Always carry a pull-through when out shooting.
5. Always unload and look through the barrels on the faintest suspicion of the muzzle touching the ground or undergrowth.
6. Always look through the barrels after the trigger is pressed with no result.
7. Always look through the barrels on the slightest suspicion of anything peculiar happening in the sound of the report, or the fall of the hammer.
8. Always look through the barrels if an abnormal amount of smoke is seen to issue from the breech after unloading.
9. Always look through the barrels if the recoil seems abnormally weak.
10. Never continue to use any cartridges from any particular lot if one or two give an altogether excessive recoil.
11. Always have guns overhauled periodically by a competent gunmaker.

I think those eleven Burrard points to avoid barrel bursts are spot on, and repair decisions, regardless of value, are probably best left to experts who can make safety decisions.

For curiosity, I looked up CIP proof houses and by chance the Czech house came up. Sure enough there are two side by side gun blow up pictures. Yes, proof loads are over pressure, but the process appears highly controlled with documentation of the gun prior to the blow up.

Maybe, a citizen or organization of a CIP member nation could somehow or another request blow up analysis. Maybe, their data can point to trends of why blow up risks are missed after a gun passes safety inspection and measurements, and is tested with a control load that the gun can presumably handle. The reason I mention this line of thinking is because there would be documentation of no obstruction, and the possibility of where to look beyond a regular default position. Only thoughts.

Now I know why Parker, L.C. Smith and other fine side-bys have an expansion joint in the top rib, near the breech. Without that joint opening at the bursting phase, well let's just say: There are FUBARS, and then there are Major League FUBARS. The olde elastic limits flew off the charts on this baby. RWTF

The reason Parker, L C Smith, Lefever & others have a joint in the top rib has nothing to do with expansion. As these guns have rib extensions with top fasteners the rear section of the rib is brazed along with the joining of the barrels & under lump. The rest of the top rib along with the lower rib is soft soldered.