Firearms Questions

quixote100104

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Greetings :),

I’ve read in various sources that, with some of the pistol designs for .40 S&W derived from previous 9mmP designs, it is possible to convert them to 9mmP with a change of barrel. Some sources I’ve seen even suggested that this could be done without even changing magazines. Does anyone out there have (or have access to) any personal experience with this practice? I’ve heard it in reference specifically to SIG and Glock pistols, but I’d be interested in input on any design.

In a related point, anyone out there own or have experience with the multi-caliber Medusa revolver? I’ve heard various stories about this innovative idea and why the weapon wasn’t commercially successful, but it would be nice to get some first hand information.

Thanks :),
 

Tiger

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9mm and .40 S&W cartridges are roughly the same length, so the system with which both Glocks and some Sigs lock their breeches could conceivably accommodate either--so long as they are the same width. The pressures generated by each cartridge however are very different and a weapon with springs, frame and slide weights built for .40 cal pressures and heavier slugs may not operate reliably using 9mm ammo.

If you are interested in a 9mm bullet, .357 Sig cartridges are a much better match. Many .40 cal weapons may be converted to .357 Sig through simple barrel changes.
 

smcc360

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Sorry I didn't see this sooner. Here's a link to the conversion barrel you're interested in:

http://www.lonewolfdist.com/Detail.aspx?PROD=972

You can actually fire a 9mm round through a .40 barrel. Once. The bullet will tumble, and the gun won't cycle properly, but it'll work. Kinda.
 

Chase

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Thanks for the photo of Lash LaRue, SMCC.

He and sidekick Fuzzy Knight were often the first feature of the Saturday matinee double bill at The State Theater in the early 'fifties.

Of course, that came after a cartoon, an episode of the current serial of The Black Commando or Superman, a news reel of how well the war in Korea was going, previews of next week's matinee, and another cartoon.

All this for 15 cents admission. A huge box of popcorn or Good 'n' Plenty candies were optional at a nickel each.
 

Summonere

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Googling “Medusa Revolver” will provide some reading material regarding that piece of engineering wonderment, and here’s one link if you haven’t already run across it.

As to swapping out .40 caliber barrels with 9mm and shooting on the cheap, yes, you can do that, but you have to use aftermarket barrels, though, because the barrel diameters differ. A 9mm barrel is smaller than a .40, so putting the same manufacturer’s 9mm barrel in a .40caliber slide will leave something on the order of a 1mm gap between barrel and the front part of the slide where the barrel pokes through. Some folks like to do this because 9mm ammo is cheaper than .40, and if you shoot much, it makes a big difference.

Some manufacturers (LoneWolf, for instance) recommend using 9mm magazines in the converted pistols to assure reliable feeding, but other manufacturers (EFK) give the a-okay for using the original .40caliber magazines. Some folks report 9mm ammunition in .40 magazines working okay, others report malfunctions to such degree that they’re great for practicing malfunction clearance. As is apparently usual, YMMV.

You can read some first-hand accounts here, though other sources abound if you Google “9mm to .40 caliber conversion“.

Aside from Sigs and Glocks, other folks run such conversions in Springfield XD pistols, Berettas, HKs, Smith&Wesson M&Ps, CZs and probably just about every other major manufacturer out there.
 

Chase

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One answer to conversion kits is to practice with the same semi-auto using cheaper or more available ammunition.

The old kit converting a 1911 from .45 ACP to .22 Long Rifle was an example.

By the same token, I shoot junk and gimmie .38 Specials in my .357 revolvers for daily practice, saving magnums for more formal occasions.
 

Summonere

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Just out of curiosity -
Why would anyone do that?

Well, for right around 115 to 150 bucks, you can shoot a whole 'nother caliber in a gun built for something else. That's a lot cheaper than buying a whole new gun, and the cost savings is even better, over time, if you can shoot cheaper ammo by using a different barrel. Right now, with some lower-end off-the-shelf ammo prices, a conservative shooting schedule of 100 rounds a week costs about $1,142.96 for 9mm, and about $2,078.96 for .45ACP, and about $612.56 to shoot the same amount in .22.

But consider this, mystery writers everywhere: suppose a character owns a .40 caliber something-or-other pistol, shoots the dickens outta that thing, is known to own and shoot the dickens out of that thing, is known also to have some bad blood with another guy, and said 'nother guy gets blasted dead by gunshot after just arguing with the dickens shooter. Oh, but he's blasted dead by a 9mm. Clearly all those 9mm bullets in the dead guy won't match the dickens guy's .40 caliber gun, unless investigators find, say, a 9mm conversion barrel that just happens to be owned by the dickens shooter, and the rifling marks just happen to match those on the bullets in the dead guy.
 

quixote100104

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But consider this, mystery writers everywhere: suppose a character owns a .40 caliber something-or-other pistol, shoots the dickens outta that thing, is known to own and shoot the dickens out of that thing, is known also to have some bad blood with another guy, and said 'nother guy gets blasted dead by gunshot after just arguing with the dickens shooter. Oh, but he's blasted dead by a 9mm. Clearly all those 9mm bullets in the dead guy won't match the dickens guy's .40 caliber gun, unless investigators find, say, a 9mm conversion barrel that just happens to be owned by the dickens shooter, and the rifling marks just happen to match those on the bullets in the dead guy.

I think (emphasis on think, not know for sure ;-) ) that forensics people can also match extractor and firing pin marks on cartridges left behind to a specific weapon, assuming they weren't all policed up by the shooter. Not that the barrel/caliber difference wouldn't be a good obstacle to throw in their way.

In my case, I was following up on a rumor I heard that some US Federal agents, who carry .40 issue sidearms but work abroad a lot, carry 9mmP barrels to allow them to take advantage of local ammunition resupply (the latter being much more commonly availible) in an emergency, including from their own 9mmP submachinegun magazines, if they use them.
 

quixote100104

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Googling “Medusa Revolver” will provide some reading material regarding that piece of engineering wonderment, and here’s one link if you haven’t already run across it.

I had Googled it, though I don't recall seeing that one. Thanks; that's the most info I've seen on the Medusa :). I'm trying to find out more about it because I'm working up a character who is an international adventurer of sorts and, if I made him a 'revolver guy', could concievably get real utility from it's unique capabilities (as well as the 'cool factor' of the exotic weapon ;-) ).

I'd be interested in finding out how hard it would be for someone with access to a custom gunsmithing shop and the nessesary funds to replicate that capability in other revolvers or to produce replacement parts for the original.

In terms of other revolvers, I'm thinking of two things. First (and, to me, most useful) would be a small frame, high strength revolver, like some of the more recent J-frame Smiths which are able to handle .357Mag loads. While the full size revolver as a primary sidearm might be somewhat anachronistic in today's world, a snubbie able to process that wide a range of ammo could be a real asset to people who go in harm's way internationally.

Second, I was tinking of a real fire-breather, like a Bowen-modified Ruger Redhawk in .454 Casull. I know that such weapons can also chamber .45 Colt and .45ACP with a modified cylinder. If the user also favored a .45 auto or submachinegun (a Mac-10 or maybe one of those new UMPs), I could see the value of being able to resupply the revolver directly from the other weapon's magazines without switching cylinders or loading moon-clips. That's assuming, of course, that the small moving parts that make the Medusa-style extraction system work can handle the abuse of firing .454s.
 

Summonere

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I think (emphasis on think, not know for sure ;-) ) that forensics people can also match extractor and firing pin marks on cartridges left behind to a specific weapon, assuming they weren't all policed up by the shooter. Not that the barrel/caliber difference wouldn't be a good obstacle to throw in their way.

In my case, I was following up on a rumor I heard that some US Federal agents, who carry .40 issue sidearms but work abroad a lot, carry 9mmP barrels to allow them to take advantage of local ammunition resupply (the latter being much more commonly availible) in an emergency, including from their own 9mmP submachinegun magazines, if they use them.

I wouldn’t be surprised that extractor and firing pin marks might well prove useful to forensic firearms examiners. After all, even casual observation shows that the standard Glock firing pin strike looks just as different from a Smith & Wesson M&P as a Springfield XD does from both. Never noticed extractor marks, much, though I’m curious if any cases have ever been solved by matching firing pin and extractor marks to a particular gun. Matches I’ve heard about have mostly been concerned with rifling marks.

That said, it’s easy enough to swap out extractors and firing pins, but a less-than-thorough villain might not think of doing so, and this failure may provide for a clever catch for some TV detective show (or book), if it hasn’t already.

As to Fed. agents working overseas and what they carry and why, I imagine it's a case of who they're working for, and in what capacity they're working. Were I writing a tale involving such matters, I'd give them two sidearms. The ubiquitous Glock 22, in .40 caliber, as the issue sidearm, all in black, and a Glock 17, 9mm, in desert tan or OD green -- idea being that the user can instantly differentiate caliber at a glance. Then I'd promptly toss the character in the dark and mix up the guns and calibers in a great big fight with badguys.
 

Summonere

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I'd be interested in finding out how hard it would be for someone with access to a custom gunsmithing shop and the nessesary funds to replicate that capability in other revolvers or to produce replacement parts for the original.

Well, as one gunsmith at a well-appointed shop once said to me, If you can think it up, we can build it. So, if your guy has sufficient funds, not a problem a-tall. Custom revolver? Custom semi-auto? Swappable calibers? Revolver: probably as easy as swapping cylinders and barrels. Semi-auto: probably as easy as building a single lower (frame and associated parts) and multiple uppers (barrel and slide and related parts).