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07-28-2010, 12:01 PM | #23 | ||||||
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I used the term "certify" inartfully if it was taken to mean "guarantee". Of course no gunsmith could guarantee anything. It would be unreasonable for anyone to even rely on such a guarantee-firearms are inherently dangerous if not used properly. However, a gunsmith could perform an proper inspection and advise someone that the barrels appear to be safe to shoot with appropriate ammo. Any guarantee could be disclaimed. But I can't find anyone willing do to even that, and I have asked well known folks you all know to do so. That is the problem for a fella like me who lacks the skill, knowledge and tools to figure it out own my own.
I think PGAC could, without risk of liabilty, publish a check list with disclaimers. It all ready publishes info on wall thickness without apparent worry. I'm gonna publish my own check list and maybe you fellas can tell me if I'm the right track: 1) wall thickness; 2) dents and bulges; 3)pits and 4) other damage. What have I missed? I understand #1. I had a dent removed by a qualified gunsmith but how do I know there still isn't a problem? Magnaflux? I have pits. How are they evaluated? Can they be measured with reasonable accuracy? Do they create a weakness in some cases, and if so, how do I figure out if there is a dangerous weakness? Would magnafluxing tell me anything about them? I have read about everything I can find on the subject but have been unable to locate an article that lays out in detail the process of evaluation. Is there something out there someone can point out to me? You all have been a great help to me and I have learned a lot just reading the forum. Thanks! |
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Barrel Measurements |
07-28-2010, 01:38 PM | #24 | ||||||
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Barrel Measurements
In response to the original question and that just posted by Ray; I am posting my opinion, which is for all practical purposes, Parker Pages opinion, but not that of PGCA or the directors.
About 15 years ago there was a question; and several opinions; relative to the weight numbers stamped on Parker barrel flats. We obtained actual weight of about 40 barrels, and plotted the actual weight vs the stamped weight. The plot indicated that the actual weight lay along a line about 10 - 15% less than the stamped weight, and concluded that the stamped numbers were the unfinished weight of the barrels. About 10 years ago, we measured the choke profiles of about 20 fluid steel 12 ga Parker barrel sets and made up a table showing mean choke tapers. About 5 years ago, we compiled the stock dimensions of about 60 Parkers and presented a frequency distribution of drop and pull. We completed that study recently with a similar analysis of pitch. During the last year we remeasured the bore diameters and muzzle diameters of about 60 Parker 12 ga guns. Dave Suponski, Dean Romig and Larry Frey measured the bores of unfinished barrels and defined the type of tooling used to form those bores. Charlie Price had noted that there was a change in bore and choke that occurred around s/n 70000. We plotted bore diameter and full choke muzzle diameter of those 60 guns against s/n. We found that typical bore diameter decreased from .750 - .760 to .730 - .735 and that full choke increased from .032 to .040 around s/n 70000. We concluded that a single contoured reamer was used to form bore and choke after 70000. We will publish a similar analysis of barrel wall thickness when we recieve 50 to 100 profiles (ie thichness vs distance from muzzle) to analyze. We hope each contributor will give a rough indication of the number of shots fired through those barrels in recent years, and note if the barrels have dents or bulges. Best, Austin |
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07-28-2010, 02:37 PM | #25 | ||||||
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Thanks for the offer to put that survey together, Austin. I'm sure it will be of interest. Frame size and marked barrel weight will be an interesting comparison when added to the mix of bore diameter and wall thickness. But. to get to my point. The safety or suitability for shooting of composite barrels is something that has not been studied and then published in our lifetimes except by Sherman Bell. We have studied this suitablility by shooting composite barrel guns without damage. We have watched others do the same. We have attended thousands of gun shows without seeing damaged composite barrels of quality that could be attributed to a general weakness of the commodity. In general, it is experience that has told us that composite barrels are generally safe, not any definitive testing in a laboratory. It is the same method used by Springfield rifle expert Michael Petrov to determine that pre serial number 800,000 1903 Springfields, generally thought to be unsafe to fire, are generally safe to fire with conservative loads. He didn't proof test or blow up a bunch of early Springfields, he just shot dozens of them for a half a century, and watched other people do the same, without damage to any of those rifles. I haven't been shooting compostite barrelled Parkers with smokeless powder for a half a century, but I have watched others doing it for that long, without damage or injury. This is the only "research" we are ever going to see, published or otherwise. After owning and collecting composite barrel Parkers and Lefevers for over fifty years, I have finally started shooting them with smokeless powder, on Sherman Bell's research. However, I do own and use bore micrometers and wall thickness gauges and recommend that others who wish to shoot these guns also procure these tools and use them.
Last edited by Bill Murphy; 07-28-2010 at 04:25 PM.. |
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07-28-2010, 03:12 PM | #26 | ||||||
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Does anybody know how many articles Shermen Bell published and where I could get copies? Where they all in the Double Gun Journal? If so, does anyone know which issues? Maybe I could find copies of them some place. I Goggled it. I think one issue was Winter 1999 but I get the sense there were more.
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07-28-2010, 04:31 PM | #27 | ||||||
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Bill, there were four articles concerning composite barrel testing in DGJ that I am aware of. I don't know if any other related articles by Sherman Bell have been published in other printed material.
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07-28-2010, 04:38 PM | #28 | ||||||
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Ray, it is hard to tell by the titles of Bell's articles which ones are the tests of composite barrels. Someone will be along soon to give you the references. Yes, they are all in the Double Gun and Single Shot Journal. I edited my last post to indicate that I have, in fact, been shooting composite barrelled guns for a half a century, but with smokeless powder about two years. I am, as I said, a convert to Sherman Bell's research. Mr. Jerry Smith, who is pictured in The Parker Story, and referred to by his "real name", Mister Damascus, in the caption, has shot Damascus Parkers and other composite guns since an BH Grade Damascus Parker was worth about $100. Jerry and I lived within sight of each other's houses in Damascus, Maryland, for more than thirty years and knew each other even before this through Parker collecting. However, although he always teased the rest of us about shooting those dangerous fluid steel guns, I stuck to my guns and shot only black powder in my Damascus guns while he shot everything up to pigeon loads in his. In our pigeon club, Damascus guns are shot on a regular basis and I have never seen a black powder shell used. I don't think any of our members have shot at a pigeon with a shell that contains less than 1 1/4 ounces of shot. No one has ever blown up a composite barrel at one of our shoots.
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Ray- Magnaflux testing |
07-28-2010, 05:46 PM | #29 | ||||||
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Ray- Magnaflux testing
My background is in code pipe welding (API- ASTM) and also pressure vessel and boiler code work- Magnaflux can be useful, BUT I would NOT trust that test alone on Damascus barrels- any rust spot, void, or raised dent, whether reset by hydraulic dent removal method or other, has stretched both the tensile and elastic limits of the metals involved- Iron will always have a way lower tensile than mild structural or even nickel alloyed steel- most structual steels used today (exception being the Cor-Ten series) have a mean tensile range of aprox 53,000 psi- that's why coded SMAW welding rods start at 60- ie: 6011- 60,000 psi tensile as stress relieved- etc-
I'd bet my pet PH 12 with Parker Twist barrels no gunsmith would ever guarantee barrels, whether Damascus or Nitro proof Steel- not in this highly litigious era- look at how all the lawyers have affected trigger pulls on factory rifles (ie: Rem 700 series) and all the disclaimers you'll find in the box with the instructions that accompany such a weapon today- Sherman Bell was a genius, also had guts and integrity- start with LP short loads (like RST or New Era)-- and rely on the research done by the other gents on the PGCA that have been shooting Damascus doubles for years- |
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07-28-2010, 06:50 PM | #30 | ||||||
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[QUOTE=Francis Morin;21975]most structual steels used today (exception being the Cor-Ten series) have a mean tensile range of aprox 53,000 psi- that's why coded SMAW welding rods start at 60- ie: 6011- 60,000 psi tensile as stress relieved- etc-QUOTE]
Tensile, meaning 'stretched or drawn out' would seem to indicate by definition and by your quoted "range of approximately 53,000 psi or 60,000 psi" a rod of a particular standard diameter.... can you tell us what that would be? |
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