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Multi-caliber revolvers.

Wednesday, September 28, 2011 Filed in: General gun stuff, Ammunition, Revolvers

Every so often I get an email asking about the feasibility of building a multi-caliber revolver along the lines of a Phillips & Rogers Medusa. There have been several attempts to build and market such a revolver over the years, and none of them succeeded. The Medusa was probably the most successful of the efforts, and even it wasn't.

Aside from the general silliness of the concept (you can't get .38 Special during the Zombie Apocalypse, but you can get 9mm Largo?!?), I've always been leery of a chamber that would handle such a wide range of dimensions and pressures. Ed Harris, of course, has first-hand experience and was able to she a lot of light on the question. During his tenure as an engineer at Ruger they were working on just such a project:

"At that time the company was also building 9mm revolvers for the French police, and .380/200 British revolvers for India, as well with experimenting with a hybrid chamber for a government customer who wanted the ability to use 9mm Parabellum, 9mm Largo or .38 Super, with clips, or .38 Special +P without the clips.

This pipe dream did not work out, because when using fast-burning powders with soft bullets, including most JHP designs for 9mm, the bullet base may upset to conform to the .379" diameter chamber mouth [editorial note: the space just prior to the chamber throat, which is exposed with shooting the shorter cartridges], resulting in a steep pressure rise of over 10,000 psi as the upset bullet base had to squeeze down again as it transitioned into the smaller diameter ball seat in the front end of the cylinder. While the result was not dangerous when firing lower powered ammunition such as .38 S&W or .380/200 British, it was more interesting with 9mm Parabellum, 9mm Federal, and .38 Super.

Worst offender was US Treasury Olin Q4070 +P+ load which has 110-gr. JHP hollowbased bullet, same as current Winchester 110-gr. component bullet and most JHP +P+ 9mm. FMJ bullets usually OK. Problems with case splits [when] firing .38 Special +P and +P+ when chamber enlarged enough in back to accept 9x19mm. With good brass cases just came out looking 3 months pregnant."

So, there you have it. The multi-caliber revolver concept is just a Bad Idea.

Speaking of unsafe, Ed passed along information about their unauthorized experiments with the then-new 9mm Federal round, which was a 9mm rimmed cartridge made to fit the a version of the Charter Arms Pit Bull revolver. (You’d think Federal would be smarter than that, but...) Anyhow, Ed tells of their fun with a "non-approved" use, and finally we have part of the answer as to why the 9mm Federal disappeared as quickly as it arrived:

 "Had some India Ordnance Factory revolvers in .380/200, copies of No. 2 Enfield which were provided as government furnished material on India contract. When 9mm Federal ammo arrived Roy Melcher was curious as to whether rounds would enter .38 S&W chamber and we didn't have any US made guns, so tried in the ROF No.2. Thanks to good range safety procedure they put it in proof box. Blew cylinder apart on first shot. Told Federal. They were NOT happy. They went on to take apart a bunch more .38 S&Ws of various makes and killed the project shortly afterward."

Ed really needs to write a book about his time at Ruger. He's got a lot more good material where this came from.

-=[ Grant ]=-

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Spontaneous deconstruction.

Monday, April 25, 2011 Filed in: Revolvers

This case has apparently been making the rounds as of last week:

ng3
Courtesy of Armed and Amphibious.


Speculation abounds, and without the gun in hand that's all we can do. There is, however, one likely cause that has historical precedent.

S&W has over the years experienced cases of incipient cracks of the frame boss underneath the barrel in several models, the 442 Airweight Centennial being perhaps the best-known example. The cause has usually been attributed to over-torqued barrels. Whether that is the case here remains to be seen.

There could have been other flaws in construction or materials, or the ammo used may have exceeded the design parameters of the frame (more precisely, the gun's design parameters didn't encompass the entire range of projectile energies allowed under SAAMI specifications.) However, the kind of damage shown would be consistent with a catastrophic failure at the point described.

Glad the shooter was (by all accounts) uninjured.

 -=[ Grant ]=-

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One of my cardinal rules.

Wednesday, April 13, 2011 Filed in: Ammunition, Reloading

Years back I remember being taught never to shoot someone else's reloads. I violated that rule only once, when I bought some "factory reloads" from a vendor at a gun show. Luckily I didn't damage anything with the shoddy 9mm fodder, but I still have the remainder -- in a sealed ammo can labeled "Dangerous Ammo - Do Not Shoot!" -- somewhere in the garage.

That cemented my rule: no reloads that I didn't make, not even one round. Why? Because you don't know if that one round came from this guy's reloading press.

Could I accidentally make a reload that achieves a similar level of destruction? Yes, but I know what my reloading precautions are; I take great pains to make sure that the ammo I reload is safe. No matter how well I might know the person proffering his handiwork, I have no idea if his attention to detail is similarly sufficient to keep me out of the emergency room.

I once knew a fellow who was a great guy. Well educated, important white collar job, meticulous in everything he did. One day he took some of his reloaded ammo to the range with two guns, a Glock and a Hi-Power. His first magazine blew up the gun, at which point he switched guns and proceeded to blow it up, too. No matter how bright people may be in the rest of their lives, sometimes they're just not cut out to make ammunition.

Neither you nor I want to be one of their "oopsies". If you didn't make it, or it didn't come from a well known factory, don't risk it in your gun.

-=[ Grant ]=-

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Monday meanderings.

Monday, August 30, 2010 Filed in: Revolvers, Techniques & Training, General gun stuff, Shooting industry

Someone sent me this link to a tale of a Ruger Redhawk whose barrel had parted company from the frame. It's an old story; not this particular occurrence, but the problem in general.

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Seems that a certain Canadian manufacturer of simulated munitions now has some competition. I've always disliked the existing company's elitist insistence on only selling to police and military buyers, and Speer, the maker of the new product, looks to change that. Their new product, Force On Force, will be sold not just to the public sector but to "professional instructors" as well. They've even got portable enclosed shoothouses available! Cool stuff from a solid, responsible AMERICAN company. (Thanks to Fear & Loading for the tip!)

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DPMS was apparently the prime sponsor for a match called the "Tri-Gun Challenge", which was recently cancelled. What's interesting isn't the match, but rather why it isn't going to happen this year. The range on which it was to be held was slapped with an order prohibiting the firing of handguns on the property. When the range/club was founded 30 years ago, they allowed all kinds of guns to be shot. In 1995 they were issued a conditional use permit for a trap and rifle range, and their neighbors apparently are alleging that the shooting of handguns violates that permit!

This is hardly unusual. My wife and I belonged to a gun club a few years back, a club which had been in existence since 1952. The conditional use permit under which we operated stated that no camping was allowed. Once a year, however, the Boy Scouts used the club facilities for a two day shooting party, with a sleepover the intervening night. The kids camped out in the classroom, but a couple of the den mothers brought camping trailers (for obvious reasons.) One particularly nosy neighbor, a recent transplant from another state, spotted the trailers and notified the county. We were hit with a similar order for violating the CUP.

People with an irrational fear of guns will always find a way to cause problems. Don't believe for an instant that because we won in the Supreme Court, the gun prohibitionists have been defeated.

 -=[ Grant ]=-

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The amazing self-destructing revolvers

Friday, May 19, 2006 Filed in: Revolvers, Gunsmithing, Current Events

Many people have been following the situation with the North Carolina Dep't of Corrections and their self-destructing S&W revolvers. If you haven't, here's a link to the story.

These pictures of one such occurrence have been floating around the net:

Pasted Graphic 79

Pasted Graphic 80

I've been exchanging emails with C.E. "Ed" Harris, who many will remember from his days as the head of Q.C. at Ruger - when they experienced a similar problem. Here's what he had to say:

"Old problem rearing its ugly head again, not really a new problem. A troublesome sporadic one when people forget about good shop practices and get sloppy.

Stress corrosion cracking is generally caused by contamination by solvents or cutting fluids too high in chlorides. Over-torquing barrels barrels creates a stress rise at the root of the thread which makes the problem worse. Microscopic examination of the failed barrels would be obvious to a competent
engineer, especially familiar to those with aerospace or nuclear power systems experience.

Ruger had a short run of this back in the 1980s when they first starting making stainless magnums. I saw a few dozen guns come back when I worked there. All were traced to one guy on night shift who was over-torquing barrels on Redhawks which didn't quite line up, instead of taking a pass off the front of the frame on a Blanchard grinder as he should have done. He also used a wrong, slippery high sulphur thread lubricant intended for chrome-moly instead of the anti-seize compound used with SS.

This condition is aggravated by tight fit of barrel threads, such as when using a class 3A, combined with high stress, high temperature, and high barrel torque. Ruger fixed their problem by changing to a looser 2A fit on the barrel threads and assembling barrels to the frames using a Loctite product to cement them solidly while reducing stress on the threads and positively preventing any seepage of cleaning solvents into the barrel threads after they left the factory."


If true, this wouldn't be the first time S&W has over-torqued a barrel: the Model 442 Airweight Centennials, particularly in nickel finish, are somewhat notorious for frame cracks under the barrel. A phone conversation with a S&W representative confirmed to me that the cracked frames were caused by barrels that had been screwed in "too tightly."

However, there's always the possibility of user error, such as the use of certain products that contain chlorine compounds (brand name removed for obvious reasons):

"Use of [lubricants containing chlorine compounds] "could" do it, as could any number of other cleaners, especially if used with an ultrasonic which enhances thread penetration."

There are certain "miracle" gun lubricant products out there that contain chlorine compounds, and have become popular amongst the more "martial" crowd. In addition, ultrasonic cleaners have been very popular at many police agencies over the last decade or so.

Well, I got an email from one of the employees at the agency, and he claims that they use Hoppes bore cleaner, and that they do not have an ultrasonic!

So we're back to the first possibility. Given Ed's expertise, I suspect that his analysis is the correct one.

-=[ Grant ]=-

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