barrel steel again

[Zonie]

My biggest concern with people "proof testing" their barrels is they only do half of the job needed to do the test properly.

In the jet engine business (where I spent 39 years) there are many parts which are proof tested but following the application of the pressure test each and every part is subjected to non-destructive tests to make sure that the pressure test did not weaken the material or create faults in the part.

These non-destructive tests ranged from fluorescent penetrant inspection (simple but superficial) thru magnetic particle inspection, ultrasonic inspection and X-ray with computer enhanced images.

The type of testing done depended on the severity of the test and the critical function of the part.

Only by doing these follow up tests could one be confident in the parts integrity.

The average do it yourself home gunbuilder doesn't have access to many of these tests so they figure, "Well, she didn't blow up! It must be safe now." when in fact the very test they did could have made a safe barrel (with normal powder/ball loads) unsafe by creating internal, sub-surface cracks in the barrel or breech plug.

If any of you choose to do a "proof test" to your assembled barrel please find a auto repair or engine rebuilding shop that has a magnetic particle inspection machine (Magnaflux) and pay them the money to test your barrel.
Tell them to ignore "non metallic inclusions" but to report any cracks that might appear in the barrel wall or in the breech plug threads.

 

[roundball]

Completely agree...I think its safe to say that any of today's top barrel companies can be trusted to produce high quality barrels far safer than anybody who runs some home made proof test using the tire swing in the back yard...LOL.

 

[jerrywh]

I would not be afraid to say that there is not one professional muzzle loading barrel maker today that would meet your standard. I respect your knowledge but a black powder barrel is not a jet engine. By your standard almost every muzzle loader in the country is unsafe.
This is the proof proceedure for all European firearms. Including pedersoli.
The standard proof of firearms consist of firing two overloaded cartridges producing 25% more chamber pressure than the C.I.P maximum pressure limit for the same cartridge in its commercial version. For pistol, revolver and rimfire cartridges the standard proof is performed with overloaded cartridges that produce 30% more chamber pressure than the C.I.P maximum pressure limit for the same cartridge in its commercial version. Voluntarily testing beyond the C.I.P. maximum pressure limit is also possible for consumers who intend to use their firearms under extreme conditions (hot climates, long strings of shots, etc.). A proof mark is stamped in every successfully tested firearm. The C.I.P. does not test any further aspects regarding the correct functioning of the tested firearm. For example aspects like the correct cycling of cartridges etc. are not part of the proofing process.

 

[jerrywh]

Agreed however, it is a good idea to have a barrel magnifluxed.

 

[FL-Flinter]

"For example: A triple powder charge with triple patched balls on top does not give me warm fuzzies that I should then assume that barrel is now perfect...just the opposite."
A load such as that is not a recognized proof test.

Zonie: My biggest concern with people "proof testing" their barrels is they only do half of the job needed to do the test properly.

Agree and agree on both of those quotes. Not proofing at all is as irresponsible as not proofing correctly. Proofhouse standards and methods have been established based on sound doctrine and all of them include a detailed before & after inspection regiment in addition to the actual live-proof methods. AFAIK, all proofhouses base the proof loads on the highest pressure, not charge, of an accepted standard service load for the given gun.

One cannot regulate nor eliminate ignorance or just plain utter stupidity from the equation whether it be during the proofing process or the shooting afterwards. Read the owner's manual for any nitro-burner and you'll see the disclaimer that excludes all warranty and liability if you use reloaded ammunition, fire the gun with the bore obstucted, ect - those types of disclaimers are in most every owners manual for everything made because there's no control over operator error, ignorance or just plain stupidity.

Reference this topic on anther forum and you'll find comment from a self-proclaimed gun builder suggesting that judging how a patch "feels" in the bore is an acceptable post-proof inspection yet even the most basic proofhouse procedures require accurate measure of specific critical areas in addition to numerous points along the entire length of the barrel. Typical proofhouse procedure is one-load at 130-135% of Pmax; two-loads at 120% of Pmax and 3-5 service loads generating Pmax. The proof loads are based on the "maximum service load pressure", not the charge volume or projectile mass (exception on projo mass is made when the charge cannot be modified to produce the correct pressure, then the gun is proofed with a 10% increase in the projo mass using the same Pmax charge)

IDK about others but once the optimum service load(s) are developed for a gun, the RR is marked accordingly. When loading, if the mark on the RR does not align correctly with the muzzle, everything stops and the load is pulled because something isn't right - the couple minutes it takes to pull the load surely isn't worth risking your own or someone else's safety.

 

[jerrywh]

I concure. Good statement. That's the facts in my opinion. By the way. I seriously doubt if any of the barrel producers for muzzle loaders today in the USA are proofing their barrels. I think they proof a random sample now and then. In Europe all the barrels are proofed on every black powder and modern firearm.

 

[Zonie]

I have no doubt that none of the factory muzzleloading barrels made in the USA have been proofed except perhaps a few before production was actually started.

Generally speaking, these muzzleloading barrels are all over designed and made of quality materials.

Back in the early days of steel making, the quality of the steel and the processing methods were not controlled like they now are.
Lets say their knowledge of metallurgy was a bit weak back then.

Prior to that, the hand crafted forge welded barrels were made using crude methods without any real control other than the skill of the blacksmith or barrel maker.
They were also made out of wrought iron which was made using very rustic equipment and methods.
Non metallics are often present in these wrought irons. It's the nature of the material.

These early wrought iron barrels and some of the early steel barrels did fail their proof tests to such a degree that most of the Governments in Europe passed laws mandating the testing of all barrels made in their country. These laws are still in effect although with the current modern technology I wonder if they are really necessary.

Needless to say, I do not advocate proof testing on any modern muzzleloading barrel made in the USA by a known barrel maker.

Old antique guns are another story and due to the materials they are made from and the revenges of time all of these old guns should be proof tested and subjected to non-destructive testing following the proofing.

 

[buckhorn]

Reply to topic--

One of my T/C drop-in barrels is a 1990s 1"x32" .40 cal. made by Green River barrels.
Anyone know what steel is used in it?