Barrel proofing, How?
 

I'm considering building a muzzleloader at some time in the hopefully not to distant future and was thinking through some of the things I would want to do to insure the safety of the gun.

I have read several places about people "proofing" their guns with double charges and/or double projectiles and firing them with firecracker fuses and such. What I would like to know is, How do you determine if the gun has "survived" the proofing?

The obvious answer is, it didn't if it blows up. But what if it doesn't blow up but is stressed and therefore weakened but not obviously damaged? How does one quantifiably measure if the proof load did/did not damage or overstress the barrel?

One thought I had was to measure the diameter of the barrel before and after to determine if it had changed, but how much change would be too much change? Maybe it should be magnafluxed before and after to show any cracking, etc. What do you all think? Is there some place where this kind of information can be found?

Thanks in advance for any knowledge you can send my way.

RE: Barrel proofing, How?
 

Why not just use the gun the way the manufacture suggested? Let them do the "proofing" and you do the hunting. I must admit that I've never heard of this before.

RE: Barrel proofing, How?
 

I'm sure a lot of guys will disagree, but I wouldn't buy a CVA as there have been enough posts about problems with the Spanish barrels, which are not proofed. Buy a TC or a Knight if you must have an in-line. Also, there is no reason to load a barrel to the max unless you're hunting Kodiak bear.

RE: Barrel proofing, How?
 

I beleive from reading his post he is going to build a muzzleloader not buy one.

Sorry I have no information on this. I'll look around and if I find anything i'll let you know.

RE: Barrel proofing, How?
 

Are you actually going to bore your own barrel? WOW.. that is really going to be a project. Good luck with this. As for the proof testing, I have no idea how they test the amount of pressure that the rifle will take.

I know the old rifles we did not trust we used to load them, tie them to a tire and fire them off with a long string. When you're young a foolish thinking ahead is not a requirement. Then you get thinking about what you just did, and what if that was the last amount of stress that barrel could take before it was ready to rupture.

Just a quick comment on BPI products. These include much more then the CVA line of rifles. You need to add Tradition's, Winchester, New Frontier, and even some others. Yes they are not proof tested to standards some people find acceptable. If that bothers you, then do as Mike said, he does not buy them. I personally own a number of them. I do not load them hot, then again I do not load my Thompson Centers, Green Mountains, or Knights hot even though they are alleged able to take the pressures.

What I am getting at is, if you own a BPI product and have any doubts as to the structural integrity of the rifle, then by all means for your own peace of mind get rid of the rifle and get something you trust. If this testing issue does not bother you, then load the rifle according the recommendations of the manufacture and shoot it. The choice is yours.

RE: Barrel proofing, How?
 

Measuring the outside dimensions is one way of trying to determine if the barrel has been stretched. Another way is to push a tight-fitting patch down the bore and pull it back out before and after firing. Any buldging or loose spots will certainly show up! Also, inspect the breech plug area and the touch hole or touch hole liner if a flintlock, and the drum & nipple seats on a caplock. I don't believe cracking or actually bursting is much of a concern, given the kind of steel most barrel makers are using these days-it is more likely to stretch or swell up if pressures are too high.

I am about to proof-test a .73-cal flintlock barrel. My first test shot will be with 200 grains of FFg powder and two tightly patched .715" round balls. Next, if the barrel survives that test intact, I plan to fire it a couple moretimes with 200 grains of FFg and one ball.

My standard loadings will never exceed 150 grains FFg and one ball, so if anything about the barrel was stressed but does not show up using the 200-grain/one ball load, I will consider the barrel O.K. for use.

Dixie Gun Works says to "use twice too much powder (whatever that is!!) and two balls/bullets" of the type that will be used in the barrel. BUT, they don't say what to check for after the shot! I think ypur question is a very valid and important one, since a barrel could survive one overload, but be damaged to the point of being unsafe.

RE: Barrel proofing, How?
 

If one builds a gun, including installing the breech plug in the barrel and instalkling the nipple & drum or touch-hole liner, it would be foolish NOT to proof test the barrel before firing the thing from your shoulder!

He's not talking about a gun he bought already made!

RE: Barrel proofing, How?
 

David - I think the best thing to do at the outset is to get a barrel blank made from quality steel - preferrablyone rated for centerfire rifles. You didn't say if you were going to bore/rifle your own, or buy an already rifled blank. If you are buying a blank (Green Mountain has a big selection) that already has the lands and grooves cut in it, and just threading it for a breech plug - you are essentially doing what gunsmiths do every day when they re-barrel.

If I was using a top quality MZ barrel, like Green Mountain, I wouldn't even worry about proofing it - unless you were turning it down so thin that wall thickness was a concern. About the only other thing that could bite you in the keyster would be if the threading of the barrel for breech plug was done improperly - such that the only a portion of the threads were holding. Then the breech plug could wind up coming back into your right cheekbone :( But otherwise this doesn't sound like a real complicated project - or at least a lot less complicated than re-barreling a centerfire rifle.

RE: Barrel proofing, How?
 

I think there are methods of non-destructive testing available now that never existed in the history of proofing. X-ray, magnetic and flourescent flaw detection, magnetic analysis, and I'm sure others. I don't know how much, if any, of the newer technology is employed by proof houses. Those techniques could physically measure the effects of an overcharge and provide meaningful results as to barrel quality - but are very likely far too costly to incorporate into typical firearms manufacture.

So, we are left with "Hold my beer and watch this!!" or pretty meaningless testing that says a particular barrel withstood a particular charge at least ONCE. Guess that leaves you still scratchin' your head, but I think it leaves the rest of us in the same boat. CVA and the like that use Spanish barrels put a proof stampon their rifles that is even less than useful in my opinion - it suggests their barrels are safe for handling loads far less than their own recommended loads generate. Some say it's a minimum required by Spanish law - well, that was never what proofing was about and should never be what proofing is about. If that is all it signifies, then why not a simple check mark or "passed" stamped on the barrel? A proof stamp on any other rifle would suggest something far more meaningful and an absolute stop sign pressure-wise.

But this reply isn't intended to be about Spanish barrels, just proofing in general. I guess Savage proofs every barrel that goes on a 10ML-II (I don't know that, just read that). The difference in quality between a soft-steel barrel and a quality American made barrel is fairly obvious even to my blurry eyes, proof stamp or no.

So, if it's a store bought barrel you can look for a quality make that has a great reputation - that's about the best you can do for now. As many muzzleloaders are sold nowadays it seems to me some industry standardization in this area would be of benefit to us all - even if it meant a few more dollars at the register. No need to go Ralph Nader, but some standardization in barrel dimensions and pressure testing sure wouldn't hurt my confidence level.

RE: Barrel proofing, How?
 

eldeguello, I have also read that in the Dixie catalog and did not understand why they didn't give more info on determining the results. I've been looking around some on the web but havn't found anything definative.

I am still in the planning and design consideration stages so I haven't determined if I will buy a pre bored/rifled barrel or go for a roll-your-own kind of barrel. I do have a blacksmith friend and several machinists in the family so I think I could do it if I pool my resources. Just not sure how much I want to bite off yet.

Itwas not my intentfor this thread to get into a discussion about various barrel makers and their quality. I am more interested in the actual process of proofing and how to measure the results of that proofing.

I appreciate the comments and information provided so far and look forward to any more insights thatare out there.

Have a great day.

RE: Barrel proofing, How?
 

IF you decide to make your own barrel, the first thing you will have to do is build a boring/rifling bench so you can drillout the bore, lap and polish it to the final land diameter, and then rifle it. I suppose a skilled machinist might be able to do the boring and lapping on a lathe, perhaps, but rifling it is another story! I don't believe you can do this oon a lathe. If you do this, I'd recommend that you consider makinga sine-bar rifling bench so that you can make any twist you want, and since making a barrel is such a major undertaking, I'm sure that after you acquire such a capability, you'll NOT be satisfied making just one barrel!!

Good luck, and keep us informed of what you do and how it goes, please!

RE: Barrel proofing, How?
 

Sorry, didn't mean to go off on a tangent but I still wasn't clear whether it was buyin' or buildin'. Building a barrel would probably be at least a 5 grand investment for me (no idea really, just a wild guess) so I would be buyin' someone else's work. :)

RE: Barrel proofing, How?
 

No problem UC, I still don't know how or even if any of this will pan out, but as an engineer/tinkerer, I get ideas for "better mousetraps" and get somewhat obsessed with the details and want to learn more about the process. More than likely I will buy a barrel blank and finish it off (hopefully not during the proofing) myself. I know of a gunmaker in my area that makes some nice Tenn/Kentuky style rifles but I don't know if he has the tooling to bore and rifle a barrel. Imight have to get in touch with him.

Eldeguello, I've seen some pictures of hand operated rifling machines but don't recall what they were called. Do you have any links to the one you mentioned or any other info that I could look up? As to whether a machinist could do the rifling, I guess it depends on the shop he has available. My father spent 40+ years as a precision machinist and has done or mademany things that suprised many people, even those in the shop where he worked. If any one could figure out how to do it with the shop he has at home, he probably could. Of course, I'm not biased about him in any way, just proud.

RE: Barrel proofing, How?
 

Check this one out...

http://www.wdsc.caf.wvu.edu/otherwebs/wdsc100jpg/DCP02725%20rifling%20machine%20Gunsmith.JPG

http://www.americanprecision.org/ModelEng.html page bottom

http://www.svartkrutt.net/longrifle.php

http://www.lautard.com/rmv.htm

http://www.border-barrels.com/workshop.htm

Google image search is agood way to find some neat stuff - sort of a back way in. I thought all those were interesting. Maybe something there to spark an idea or cost you some money.

RE: Barrel proofing, How?
 

Thanks UC, those are some great links and information.

RE: Barrel proofing, How?
 

I did a search on sine-bar rifling bench and got quite a few hits, butr what I learned about rifling ML barrels came mostly from Ned Roberts' (.257 Roberts) book, THE MUZZLELOADING CAPLOCK RIFLE.

This book describes, and has pictures of, a great many ML rifle-making tools and gadgets. The old-time smiths had to hand-make their tools including boring machines, bits, and rifling benches before they could even think about making a gun!

The sine-bar type rifling bench is pretty simple, at least in concept, and I believe it would be easier to make than the kind that use wooden shafts with the rifling twist carved into the shaft. With this kind, you need a separate carvedguide shaft for each different twist. The sine-bat bench will allow you to cutgrooves varying from no twist at all to as tight as you'd ever wantit.

This is a picture showing part of one. The bar on the left can be set to any angle, which controls how fast the rack & pinion gear engagement permits the rifling cutter rod torotate as it is drawn through the bore of the barrel. Changing the angle of that bar changes the twist of rifling you are cutting. This picture is of a Pratt & Whitney sine-bar rifling bench. The ones I've seen were made of wood, except for the bar, the gears, and the rifling rod & cutters. Since the bar seems to be set parallel to the cutting rod station in this picture, if used as set now, it would cut straight grooves......

RE: Barrel proofing, How?
 

Thanks for the good info and more ideas to research. I've still not found much on quantifying the results of proofing so if anyone out there knows of some, please let me know.

Thanks again for all the help.

RE: Barrel proofing, How?
 

ahhhhhh my shop teacher showed us a video on building a flintlock......and it showed them bore the barrel and rifle it ect...and proff it.......i dont think it said much about proffing....just that it was loaded with a charge of BP that was much higher then one would normally load with.........not much help..i know...but it was an interesting video...........im SURE theres info out there somewhere..........where to look....no idea....maybe contact TC or someone that proffs barrels and tell them you were wondering how they do it and how to tell if the barrel was damaged or unsafe.....im sure if you talk to the RIGHT person they can help you......or maybe a gunsmith or someone that does custom work could help better........hmmm...interesting project......i myself want to do the same and build a flintlock....but i dont know about boreing and rifling my own bore

RE: Barrel proofing, How?
 

You might try contacting one of the proof houses such as Birmingham http://www.gunproof.com/ and see if they can recommend a procedure or refer you to another source of info.

RE: Barrel proofing, How?
 

Quote:

---

Proof - The test-firing of a gun with an extra-heavy load, at an official establishment, to verify the safety of a gun, which is then marked with formal stamps showing, among other things, the loads for which it is intended.

Most civilized countries have proof houses, run either by the government or by the trade association under the regulation of the government. In these countries, every new gun must pass proof before it is sold. The United States, the most litigious country in the world, has no proof house. Perhaps for these reasons, American shotguns are often stronger and heavier than their European counterparts.

---

This is all I could find on how to proof a rifle barrel. It would sound like you over charge it, get the heck out of the way, fire it, then check the barrel for damage. If the barrel dimensions have not changed and it took say a two and a half time the normal load, one would then estimate a normal load would be of little concern to the shooter.

RE: Barrel proofing, How?
 

Well, as you no doubt know, the DGW catalog has proof-load tables in the back, which show whatthe proof load for various gauges was back in the 19th century -if I recall correctly, these are British proof loads (and perhaps some Belgian). But again, it doesn't describe what to look for AFTER the load is fired!

Another problem is that our powders today are different from those used when those proof tables were developed. And who know how much different!

RE: Barrel proofing, How?
 

Well I've been in communication with the Birmingham Proof House as well as a gunsmith friend and here is some of the preliminary info. I'm still waiting on some clarification from BPH, they have a whole manual of specs based on gun type etc. I'm trying to get the specifics for black powder guns.

The gunsmith friend suggests that there should be no change in dimentions in the area of and nearthe chamber. He also noted that a change of 1 or 2 thousanths probably would still be safe but would prefer no change. He also said that the nipple would most likely blow out before the barrel would bulge, at least that's what he has seen when people have brought in guns that were over loaded or shot with smokeless loads. In his experience, a barrel is much more likely to fail from short starting the projectile than from overcharging the barrel. This of course is not an endorsment to overload a barrel, always follow the manufacturers load recomendations.

Still waiting on other sources of infomation and will post it when it arrives.

Have a good day.

RE: Barrel proofing, How?
 

Thanks for the information, Dave. BTW, where do you live in N.M.? I have lived in both Alb. and Las Vegas, and my brother still lives in Alb.

Great place to live & hunt!!

Larry

RE: Barrel proofing, How?
 

I live in the east mountain area, Edgewood to be specific. Its about 20 min to Albuquerque. I work over in Rio Rancho.

RE: Barrel proofing, How?
 

Great! I used to hunt elk in the Pecos Wilderness NE of Santa Fe, and deer in the Turkey Mountains near Ocate! I sure love N.M.!!