M1 carbine wildcats

[Gifted]

I got curious about this, after reading those threads on the carbine, and seeing that a .45ACP fits loosely(VERY loosely) in the magazine. It's much too short, but I was looking at the fact that it fit at all. Got me wondering, so I pulled out the gun, made some measurements, and did a little bit of thinking.

This isn't something like that 5.7mm cartridge, which is necking the .30 carbine brass down, this is putting a larger caliber in the gun. I'm kind of curious about whether anyone's tried it, but I thought I'd throw what I'd come up with out there too.

I was first looking at the magazine size, but that's irrelevant, the important dimension is how big of a cartridge you can make a chamber for. The barrel threads into the receiver, and that hole is about .637". Not sure how much leeway you'd actually have there, since part of the chamber is here, and it has to be thick enough to hold the barrel and receiver together.

My initial thought was to turn the tapered .30 cartridge to a straight walled one, but Measuring a few cases waiting to be loaded tells me they're about .012-.014 at the mouth, and I'm not sure that would support being stretched. This would only give you about .320, and I'm not sure that would give enough extra weight to be worth it.

Looking back at the .45, The base(not the rim) is .480 according to Lymans, which would give the part of the breech in that threaded part of the receiver a thickness of .178. Not sure if that would be enough, but that would allow you to build a .450 caliber cartridge and gun. Regardless, anything larger than the .30 looks like it would need a rebated rim, since there's not much room to enlarge the bolt face. Now, this would be a pretty low pressure round, since I can't go over the limits of the short-stroke piston, but I think it would still be pretty respectable.

Anyone want to chime in on how crazy I am?

 

[Harley Quinn]

Several people have converted the little rifle to a bigger cal. I am not sure what it takes to accomplish it though.
Take a 223 and cut it prior to the shoulder 35 cal???

:uhoh :http://www.6mmbr.com/223Rem.html

 

[GCW5]

I remember seeing sombody was converting them to .45 Whinchester and 500 AE. It seems like it was a Gun Digest or a Guns & Ammo anual 4 or 5 years ago. I also remember that there is a converson with a 30 carbine cas necked to .22.

 

[M2 Carbine]

Gifted
M1 carbine wildcats
This isn't something like that 5.7mm cartridge, which is necking the .30 carbine brass down, this is putting a larger caliber in the gun. I'm kind of curious about whether anyone's tried it, but I thought I'd throw what I'd come up with out there too.

In the 60's the carbine was made in 9mm and 5.7 Johnson.

The 9mm wasn't a commercial success. People didn't want a less powerful round. The 9mm and 30 Cal Carbine ammo cost about the same.
Plus the 9mm uses a faster burning powder that didn't work the action well.

In the 80's I found an original Iver Johnson in 5.7 Johnson and later re-barreled one of my Carbines in 5.7.
I lost the original in a fire but still have the second one.

Carbine brass is necked down to 22 with a special die.
The bullet was supposed to be a 40 grain Hornet.
The muzzle velocity from the original length barrel is 3,000 fps.
It's a hot little Wildcat round but it never caught on.

5.7 Johnson-5.7 FN-5.7 FN fired case

 

[Harley Quinn]

Carbine brass is necked down to 22 with a special die.
The bullet was supposed to be a 40 grain Hornet.
The muzzle velocity from the original length barrel is 3,000 fps.
It's a hot little Wildcat round but it never caught on.

I have one of these(5.7) and 5 barrels I bought several years ago.
I still have them
I'll sell a few if anyone wants one

 

[Anteater1717]

Looks like with a new bolt it could be made to take the FN 5.7.

 

[Gifted]

That might be an interesting conversion. One of the problems with the FN round is not enough guns for it.

THe idea here though, was to go with a heavier bullet at or just below the current velocities. The 5.7 Johnson goes the other way though.

Heck, when I was looking at just hte magazine, I was thinking about a .600 wide case necked down to .500 for the bullet, but the way the barrel goes in to the receiver, I didn't think it would be strong enough.

 

[Browning]

In addition to the 5.7 Johnson/Spitfire mentioned by other people I remember there being some .44 Automag and .45 Win Mag conversions as well according to various things that I've read. Most of it was just rumors though and I've never actually seen any of these in person, in a picture or in an ad.

In this article from Gun Zone they talk of M1 Carbine in Finland being converted to fire a 7mmx33 Sako round, a 7.63 "Mini-Whisper" and 7.62X25 conversions done in Australia. This is probably THE most informative article on different calibers for the M1 Carbine that I can find anyway.
http://www.thegunzone.com/carbine-wildcat.html

Then in some of these other links I've found talk of 10mm, 9MMX25 Dillons and several other M1 Carbines that were supposedly made in other calibers. All of this stuff sounds like some pretty expensive custom stuff and none of it is from a factory manufacture at a decent price.

http://www.thehighroad.org/showthread.php?t=54647

http://marina.fortunecity.com/harbour/347/10mm07.html

http://www.northeastshooters.com/vbulletin/showthread.php?p=215776

http://www.jouster.com/cgi-bin/carbine/carbine.pl

Not a single picture or a claim that someone owns one or a picture anywhere, so if they do exist, someone's hiding them all and not letting them see the light of day as far as I can tell. Hopefully before I die someone will make an M1 Carbine type weapon in a caliber that has more pop that a .30 Carbine. I don't care if it's 10mm, 9MMX25 Dillon, .44 Automag, .44 Mag or .45 Win Mag, if they build it and it's reliable and accurate I'll buy one and shoot it alot.

If I win the lottery I'm building my own gun company and hiring some weapons designers to build me one (or ten) and I'll sell them at a fair price. If it were me (yes, I'm dreaming) I'd probably pick the 10MM as it's an auto cartridge that's established that you don't have to reload in order to shoot and it doesn't have a rim the way the .44 Mag does so there would be less problems with it being a semi-auto.

 

[Harley Quinn]

The M1 Carbine is a rifle round...110 grain at around 1200 energy
The others are Pistol rounds and even with the heavier bullet does not
compare to the ability of the 30 cal to do the job.

It has been discussed many times about the ability of the 30 over the pistol rounds, still going on and will until another round is built for the little shooter.

 

[eldon519]

I've never messed with one, but if you said a .45 ACP round will fit but is too short, you could try making something out of cut-down .308 or .30-06 brass. It's about the same diameter externally. The brass should also be capable of handling much higher pressures than .45 ACP cases. Maybe you could just make a super-.45 ACP.

I think I remember reading the same article these guys are talking about using the .50 AE. I believe they had problems with the recoil cracking the stocks. I think the company was LeMag.

 

[cane]

Then there was the "Vulcan", a .44 mag pump action. It was made by deactivating the gas system and attaching a pump forearm to the operating rod.

 

[Jim Watson]

Cut .30-06 brass off to .30 carbine length and rechamber. Ackley shows two slightly different versions, the .30 Kurz and the .30-30 Carbine.
Must open up bolt face and extractor, maybe fiddle with magazines.

.375/.38-40. Cut .30-06 off to the length of a .38-40 and size down in that die. Load .375" bullets to make up for the thick brass of the shortened '06.

.375 Shannon. As above except it is a straighter case with more shoulder and would take its own dies instead of adapting .38-40.

Rebarrel by monobloc conversion of the carbine barrel just ahead of the gas block. Open bolt face, etc. 15 rnd carbine magazine holds 7 .375s with little work. Ballistics about like .35 Remington but I don't know where to get the 200 gr .375" bullets.