Author Topic: To proof or not to proof a barrel.  (Read 32547 times)

SPG

  • Guest
Re: To proof or not to proof a barrel.
« Reply #50 on: January 22, 2011, 08:09:41 PM »
Gentlemen,
I have been reading this thread with much interest as it brings up many issues that were debated concerning barrel steels years ago. As in most debates, there are some good points on each side. However, I agree with Bookie and Dan when it comes to the subject of proofing one's work. It doesn't make sense to not test-fire, at least, a newly made firearm before putting it to your shoulder. I think that this is simply common sense and should not have to be explained.

I am the "friend" that Dan refers to in his post about having the conversation with a well-known barrel maker who, when asked about leaded steels, said that he would rather fire a correctly welded skelp barrel than one of leaded screw stock. His name was John Krieger. This was a private conversation and John related his opinion as a barrel maker concerning the steels in question. I have had nearly the same conversation with Ernie Stallman of Badger Barrels, Jim MacLemore, and Frank Green of Bartlein Barrels. All expressed the opinion that leaded steels were not something that they considered gun barrel quality. The main problem being of inclusions, mainly lead, that would show up in individual blanks due to quality control.

I have a Douglas blank (circa 1980) that I believe has those inclusions. I shot it for years. I always wondered that there were fine streaks that wouldn't take browning. At the time the gun was made I thought it was simply the nature of browning. The barrel was proofed and, like I said, I have shot it for years. A couple of years ago I thought that I could feel an edge on one of the streaks. I had Dan replace it with a Green Mountain barrel. When I described the barrel to Mr. Krieger he simply smiled and said, "Not shooting it any more, are you?" He also said something that stayed with me- "consider that a leaded steel barrel that has inclusions is basically soft-soldered together."

There are a lot of people who have dogs in this fight for one reason or another. Some have defended the use of leaded steels either from their use of those steels or because, in light of their own research, consider them to be adequate when used with black powder and it's relatively low pressures... when correctly loaded. However, to reject the experiences of someone who has personal experience with the performance of barrel steels during manufacture, and has collected information on known barrel failures, is extremely short-sighted. Forewarned is forearmed and I consider Dan's postings to be valuable contributions to the discussion, as I do the collective wisdom, experience and opinions of four other professional barrel makers.

I have some '70's and 80's vintage firearms, collectable, that I regularly shoot. They have barrels from that era when the steel quality became an issue. I'm re-barreling them and preserving the original barrels. That's just me. Everyone is free to do what they want, especially when they take into consideration their own experiences and knowledge on the subject.

The greatest advantage to forums such as this is the free exchange of information. Obviously, some of that information will be of more value than other. However, a healthy discussion carried on in an intelligent manner benefits us all and a wise man will consider all opinions.

Just my thoughts,

Steve Garbe  

Offline Don Getz

  • Hero Member
  • *****
  • Posts: 6853
Re: To proof or not to proof a barrel.
« Reply #51 on: January 23, 2011, 12:01:22 AM »
Roundball.......I've been following this thread from the beginning but I refsuse to get into it again.   The first go-round
on this subject back in the 80's was just too time consuming for me, cost me too much in time, kept me from making
barrels.    By the way, we are still using the same steel to make our barrels....................Don

Offline Dphariss

  • Hero Member
  • *****
  • Posts: 9920
  • Kill a Commie for your Mommy
Re: To proof or not to proof a barrel.
« Reply #52 on: January 23, 2011, 12:20:44 AM »

I lied I am back... ::) I had a phone conversation and it started me looking in old magazines again.

You need to find the Buckskin Report articles.Specifically the Oct 1981 and later issues and the earlier ones they cite.
There are a number of rather extensive write ups. Both sides of the argument. Pages and pages and pages. I have some of it scanned it but it just takes up too much space.

Including the fact that Montana Barrel Company was switching to 1137 GBQ since they were apparently going to be making barrels for smokeless applications.  GM BTW uses 41xx series for cartridge barrels.
Could have been related to the failures of 12L14 schuetzen barrels.






Yeah its smokeless. But my position if that the barrel should not have failed, period and if it DID it should not brittle fraction and throw fragments.
There are very similar "events" involving MLs. But often they are usually not by the guy who broke the trigger.


It should not have failed in this manner. Bulging and splitting is not the same as breaking off with virtually no bulging is a sign of BRITTLE FRACTURE.


In all the comments about the use a leaded screw stock people who take the time will find that the only barrel makers that defend its use  are the ones that use it. This alone should be a red flag. Once they make barrels from the stuff they are compelled by liability to defend it even when they start making barrels of some other steel. Then there is the "handloader defense" since any rifle barrel made of modern steel will stand massive over pressures, most of the time, failures are immediately put on loading error... The safety net for barrel/gun makers.

Barrel makers who do not use cold rolled leaded steels, and I suspect some have sold more barrels than the ML trade has used since the 1950s, have no use for the stuff. In fact one, Ernie Stalhman who I used to buy barrels from before he retired, would go on an instant rant if you mentioned leaded steels. He would not allow leaded steel in his plant. The mention of this stuff would often slow the ordering process. And he did make a lot of barrels. Even some ML barrels but he would only make 35" and under...
Most makers of ML barrels are hobby shops in comparison.

Dan
He who dares not offend cannot be honest. Thomas Paine

Offline smylee grouch

  • Hero Member
  • *****
  • Posts: 7910
Re: To proof or not to proof a barrel.
« Reply #53 on: January 23, 2011, 05:10:03 AM »
What a great discusion, diferent strokes for different folks. Just a short note about original post, I found an phamphlet from GRRW when they were in Roosevelt and the proofed load sugestions. Acording to Bill one patched round ball was what he recomended on top of a powder charge of aprox. ball weight. Just some more food for thought.   Gary

Offline Blacksmoke

  • Hero Member
  • *****
  • Posts: 875
  • "Old age and treachery beats youth and skill"
Re: To proof or not to proof a barrel.
« Reply #54 on: January 23, 2011, 07:02:58 AM »
Further more - I thought this was a Longrifle Forum!  Why are addressing the dangers of firing smokeless powder in gun barrels that were made of steel which was not designed for nitro??  When you examine the explosive properties of nitro powders and understand their behavior it is no wonder that there have been barrel failures using 12L14 steel!  I have all of those articles that were published in the Buckskin Report and pondered many times back in the early 80"s.  I was just beginning to get into the rifling business then and it scared the h-ll out of me.  Then I subscribed to some common sense and calmed down because I realized that blackpowder pressures in round ball guns are less than half of those in smokeless!  More like 1/3rd.  I pressed on as did all of the "small" time barrel makers.  30 some yrs. later I can truthfully say that I consider the largest threat to safety in the Contemporary Longrifle maker's realm is bad workmanship!!  Such as the installing of a breech plug with not enough threads to give a good safety margin or the theads are not engaging 99%.  If there is any lateral  play in those breech threads I consider them un-safe! I like an all most interupted fit of threads.   Also my breeches extend to 3/4" in length.  I think that we need to focus more on doing GOOD workmanship than discussing the properties of nitro powders.     Again my thoughts ;)    Hugh Toenjes
« Last Edit: January 23, 2011, 07:16:23 AM by Blacksmoke »
H.T.

Daryl

  • Guest
Re: To proof or not to proof a barrel.
« Reply #55 on: January 23, 2011, 08:44:59 AM »
What a great discusion, diferent strokes for different folks. Just a short note about original post, I found an phamphlet from GRRW when they were in Roosevelt and the proofed load sugestions. Acording to Bill one patched round ball was what he recomended on top of a powder charge of aprox. ball weight. Just some more food for thought.   Gary

Gary - perhaps I missed something - are GRRW barrels mentioned somewhere as to barrel steel? I'd like to know.  I guess I haven't proofed mine yet - as that would be 480gr. of powder and a single 480gr. ball. I've only shot 330gr2F with a single tightly patched ball - but didn't like it much. :D

Offline Don Getz

  • Hero Member
  • *****
  • Posts: 6853
Re: To proof or not to proof a barrel.
« Reply #56 on: January 23, 2011, 04:33:05 PM »
I think the moderators should stop this discussion.    The only thing it might do is to scare away any new gun builder,
thinking, "gee, do I really want to build a "bomb" ", maybe I should just take up golf.   One should always remember, when shooting any gun, muzzleloader or cartridge, when you pull that trigger it is creating a rather powerful explosion
right here in your hands.   Let's not scare them away.................Don

Offline FL-Flintlock

  • Hero Member
  • *****
  • Posts: 2176
    • Fire & Iron Mfg.
Re: To proof or not to proof a barrel.
« Reply #57 on: January 23, 2011, 05:00:11 PM »
Dan Pharris,

There's a lot of discrepancies in your statements that need to be clarified and you didn't directly answer any of the questions I posed.  I'm not arguing alloys; people who use nitro powder in a muzzleloader; people who don't pay attention to what they're doing when loading; people who partake in the stupidity of "speed shooting"; people who don't know how to properly load or anything else.  I'm "asking" you to answer to the following questions based on the information and statement you provided in this forum.

The LaSalle letter, item 4 concerning "Gun Barrel Quality" steels states that
Quote
"A thermal treatment after all machining and fabrication operations which will assure complete recrystallization of the material.  Only a full anneal or quench and temper operation will fill this need."

1- Would you please explain what type of thermal treatment you give your barrels when you're done working on them and what process do you use.  On numerous occasions you stated that you use high-temperature silver braze to attach accessories to the barrel ... I'm asking if you again do a complete thermal treatment on the barrel post-brazing since you changed the properties of the barrel, at a minimum in the heat affected zone, during the brazing process?

2- When you make your breechplugs, do you heat-treat the plug itself as a separate piece or do you just heat treat or anneal the entire barrel assembly after the plug is installed and all other work is done?

3- The Buttress style thread is the strongest thread design, it is used on large artillery gun breeches because of its superior strength so why is it not used on small arms?  

4- When you install the breechplug, do you adjust it to a known torque value or do you use a compression formula based upon contact with the boss & face?  Also, what formulas do you use to determine said torque or compression rating and do the formula(s) take into account thread engagement loading strength based on contact surface mapping of the actual assembly or do you use assumed constant values in the calculations?

Related to this question is your statement about "sealing the bore":
Quote
A friend built a lot of guns using bolts for breech plugs. They are made to a specification. The taps used are made to the same spec.
There will be a certain amount of slop in any threaded joint. If that worried about thread fits. The standard fit is 75% IIRC, then make your own breech plugs so that the tolerance can be controlled. But the fit is not THAT critical if the bore is sealed.[/u] Re: powder chamber on breech plugs « Reply #35 on: December 18, 2010, 01:38:12 PM »

I'm curious to know your secret on "sealing the bore" with a breechplug when there's no intermediate gasket material involved.  I've worked on a lot of stuff and any time you have a connection with non-tapered threads, some type of additional gasketing material is required to achieve a "seal" between iron-base alloys.  Looking at the breechplug fitting pictures you posted, you're showing the steel plug mating to a flat steel boss in the barrel breech - in the above quote you stated that the amount of "slop" in threads isn't really critical if the bore is sealed ... my questions are:
A- How do you achieve the alleged "seal" and how do you test the seal?  I'm curious as to if you pressurize the bore to 20ksi or so with nitrogen or what ... there has to be some form of bench testing you use to establish the quality of the "seal" - I mean it's impossible to perform any kind of "seal test" using powder burn because the massive volume of fouling generated by the burning powder would create a false positive.  
B- The threads that are retaining the plug and therefore the thread strength is critical to maintaining the alleged seal - thus, if the threads fail will not the alleged seal be compromised as well?  How does the alleged "seal" prevent mechanical strength failure of the threads?
C- In other threads you claim a certain breeching style is "the strongest" but the accompanying drawings show the vent liner penetrating the load-bearing threads of the plug - please show the engineering data that proves why that particular breech style is allegedly "the strongest" and how one achieves a stronger threaded breechplug connection by removing a portion of load-bearing threads on the plug joint.

5- Can you please explain the difference between a bar of steel that is cold-rolled and a modern gun barrel that is formed by cold-rolling or cold hammer forging?  I ask because in another thread you said that rolled threads were stronger than cut threads however the thread rolling process is done cold ... and if you're cutting threads in the breech or on the plug, are you not making a weaker connection and should therefore seek out barrels and plugs with threads that are formed in a cold-rolling process?  Reference your statement:
Quote
Bolts have rolled threads which are much stronger than cut threads.  Re: powder chamber on breech plugs « Reply #32 on: December 17, 2010, 10:56:51 PM »

In this thread you stated:
Quote
I have no idea what the hammer forging process entails[/u] but I suspect that the barrels are stress relieved afterwards. Its not done because its the best way to make a good barrel its done because its CHEAP in the long run and not very labor intensive.[/u] Re: To proof or not to proof a barrel. « Reply #53 on: January 21, 2011, 11:38:36 PM »

If you don't know what the hammer forging process is as you claim in the first sentence, how can your very next sentence be presented as a statement of fact condemning hammer forged barrels?  Would you not need to have at least a basic working knowledge of the process and outcomes in order to make the statements you did in the second sentence of the quote above?  Sorry Dan, that's just confusing when you say you don't know anything about X but in the very next sentence say with absolute fact that X is bad ... doesn't make sense to me and some clarity would be in order to explain your conflicting statements.

And, can you please explain the difference is between forming steel stock by cold-rolling and making a nitro shotgun barrel using a cold-rolling process?  Again, I'm asking for clarification on your conflicting statements because it's just not making sense to me that you praise cold-rolled bolts as being superior in strength to a machined fastener but then make the statement that anything cold-rolled is inferior to something that's machined.

Need some clarity on this statement too Dan:
Quote
I would not equate the gun barrel makers not quenching and annealing GB quality steels after all machining processes are done with the practice of using low quality cold rolled steel for barrels. Re: To proof or not to proof a barrel. « Reply #53 on: January 21, 2011, 11:38:36 PM »

You lost me on that one Dan ... Are you saying that gun barrel makers don't heat-treat after all the work is done, and if so, does that not go against what is clearly stated in number 4 of the LaSalle letter concerning gun barrel quality steel that clearly states the barrel must be heat-treated after ALL work is done?  Is your second sentence implying that all cold-rolled is low-quality or are now making the distinction that there is a difference between "low-quality cold-rolled stock" and "high-quality cold-rolled stock"?  Not arguing, just asking you to clarify your statements.


6- After you overcharge the barrel and it doesn't blow up, what inspection method (IE: X-ray, ultrasound, eddie current?) do you use to ensure that the overcharge did not cause internal fracturing or some other problem that may result in a failure at a later date with a normal service charge?  What pressure testing equipment do you use to show that your alleged "proof load" did not exceed the proportional limits of the barrel assembly?
« Last Edit: January 23, 2011, 05:09:18 PM by FL-Flinter »
The answers you seek are found in the Word, not the world.

Offline Dphariss

  • Hero Member
  • *****
  • Posts: 9920
  • Kill a Commie for your Mommy
Re: To proof or not to proof a barrel.
« Reply #58 on: January 23, 2011, 05:34:45 PM »
FL:
Your lost a lot more often than you know.

Dan
He who dares not offend cannot be honest. Thomas Paine

Offline tallbear

  • Global Moderator
  • Hero Member
  • *
  • Posts: 4053
  • Mitch Yates
Re: To proof or not to proof a barrel.
« Reply #59 on: January 23, 2011, 05:42:48 PM »
Morning guys!!! Once again I believe this subject has run it's course.Both sides have been given the opportunity to present their case AGAIN!!This topic has been covered here many times in the past, a search through the archives will yield more on past discussions much the same as this one.

Mitch
« Last Edit: January 23, 2011, 05:43:34 PM by tallbear »