Improved M1 Carbine (update)

[GrumpyOlGuy]

(Reviving a thread from a few years ago) There has been ton of discussion about M1 Carbine (good: Handy, light); bad: under-powered, weak, short-ranged). The single biggest mistake made by Winchester was not using a pointier, higher ballistic coefficient bullet. Going from the round nose (BC ~0.178) to a pointy bullet (BC ~0.275 to 0.300) would have increase the effective range by about 150 to 175 yards. I consider the as-built Carbine to have an effective range of about 250 yds (where the bullet had about the energy of a 9mm Parabellum (115gr) at the muzzle). At 450 yds, the high BC Carbine bullet would have the same energy as a .38 Special +P at the muzzle. At 225 yds, its a .357 magnum (muzzle energy), 75 yards further out than with a standard Carine round (equiv at 135 yds). Who could argue with that for power?

If a 110 gr, 0.275 BC bullet were used, the bullet at 400 yds would have the same energy as the 9mm/115 muzzle. At 375 yds it would have the same energy as a 230 gr .45 Auto at the muzzle. I think many people would find that energy satisfactory. (All calcs from standard ballistics calculators).

The could have been done any number of ways (bottle-necked case, slightly longer action (~ 0.2 inches) to accommodate the longer bullet). Two bad this wasn't done at the time - a much more effective weapon (with a 150% increase in effective area covered) could have been had for nearly no additional effort. I know, i know -- it was only to be a replacement for a pistol... that kills stuff at 250 yds.

Oh, well.

 

[CapnMac]

Well, Winchester to save essential time for the Carbine competition (which they just barely met, with only like 45 minutes to spare), based virtually all of its Carbine off the 32 Winchester Self-Loading, both the cartridge and the weapon. (That latter is why the magazine design is so sub-optimal.)

War Department had, notionally, begun their thinking with the .32pederson (aka 7.62 french long), so a "more modern" round, like the .32wsl was seen as a bonus.

This also fit into the original notion of the Carbine as a replacement for side arms for second & rear echelon troops, who would not be expected to engage beyond visual range, perhaps 100-150 meters. Which would be 3x or 4x reasonable handgun engagement ranges.

The use of the carbine as a Squad and Platoon Leader arm was not anticipated in the original design, and that "blurring" of tactical utility mostly came about from just how easy it was to make as many Carbines as were mass produced.

Now, the .30carb round does have a lot of potential. The case volume and diameter and LOA offer all manner of possibilities.

The real problem being the limitation of the magazine, a last minute (as in 8-10 hours before testing) "fix" of a kludged existing magazine adopted by the expediency of an immediate international world-wide war (which can have the effect of blurring people's imagination, even engineers').

 

[Bwana John]

.22 Spitfire (5.7mm Johnson)

 

[someguy2800]

I've always thought that the perfect round for the M1 carbine would have been 300 blackout. A 110 grain spitzer at about 2400 fps would have been a nice bump in effective range and power, and I bet it would have made the m1 carbine a more accurate and reliable weapon to boot. If they had done something like that we would probably consider that to be the start of the intermediate cartridge revolution rather than the 8mm kurz. And yes of course I realize that 300 blackout didn't exist for another 50 years, but in hindsight I think something similar to that would have been about perfect and would fit with relatively minor modification to the design.

 

[Jim Watson]

Trivia: The proof load for .30 carbine was a 150 gr M2 bullet, probably with the 110's powder charge.

 

[BreechFace]

I've always thought that the perfect round for the M1 carbine would have been 300 blackout. A 110 grain spitzer at about 2400 fps would have been a nice bump in effective range and power, and I bet it would have made the m1 carbine a more accurate and reliable weapon to boot. If they had done something like that we would probably consider that to be the start of the intermediate cartridge revolution rather than the 8mm kurz. And yes of course I realize that 300 blackout didn't exist for another 50 years, but in hindsight I think something similar to that would have been about perfect and would fit with relatively minor modification to the design.

Like this?

 

[BreechFace]

I don't consider the 30 Carbine to be a firearm with "a lot of potential," I think it's reached it's potential in today's market with good commercial SP hunting/SD loads. Now maybe a spitzer projectile might breathe a bit more distance and energy at distance, but really it's kind of inconsequential.

Off the top of my head, I believe the twist rates on M1 Carbines are 1:20, so getting a longer spitzer projectile to stabilize well and not have it's stability fall apart in flight would be a main concern in loading for the M1 Carbine. M1 Carbine bullets are short in length and are matched to the twist rate. I'll try and dig up my projectile lenght spreadsheet and post the difference between a 110gr M1 Carbine SP projectile and a 110gr VMAX; there in lies a big problem with loading with spitzer bullets for the M1 Carbine, along with projecting too far into the case with the spitzer to be fed from the M1 Carbine magazine COAL restriction.

We are talking about a case capacity of 21gr H2O on a straightwall with a max pressure of 40k psi; I would say there's not much more to work with for improving.

I look at my M1 Carbine and say to myself, its good to 100 yards and in. And I say all the above with an affinity for the M1 Carbine.

 

[BreechFace]

Just found looked in my projectile length database I had saved.

110gr 30 Carbine RN - 0.602" Length
110gr VMAX - 0.926" Length

That's a 35% increase in length for the 1:20" 30 Carbine barrel to have to stabalize. Typical twist rates for

I don't think there is much room for improvement in the M1 Carbine that already hasn't been done with good commercial SD loads.

 

[BreechFace]

Just plugged in the 110gr VMAX, minimum twist rate is 1:13". So trying to load spitzer projectiles in 1:20" twisted M1 Carbines is going to be unfruitful outside of any really short spitzers which defeats the OP idea of breathing life into the 30 Carbine with higher BC projectiles.

 

[trackskippy]

I dont see why people get all wound up about this sort of stuff. The M1 Carbine is what it is, worked very well in its designed use, and if you can shoot, you can easily put a couple of quick rounds on target at realistic distances.

While it is dated, Its still a handy little gun that most anyone can shoot well with. And the same can be said about similar guns that came after it that replaced it, that take the caliber issue to another level.

If you have a Carbine, you're still fairly well armed and have a fun little gun to play with (or worse if need be). Id be happy with that and not get to wound up.

 

[Jim Watson]

Just plugged in the 110gr VMAX, minimum twist rate is 1:13". So trying to load spitzer projectiles in 1:20" twisted M1 Carbines is going to be unfruitful outside of any really short spitzers which defeats the OP idea of breathing life into the 30 Carbine with higher BC projectiles.

I think he was in would'a should'a could'a mode. Certainly if the Army had specified a spitzer bullet they would have rifled it to suit. Probably a 10 twist so they could use the same setup as .30-06.
Probably what Germany did, the early intermediate ammo work was done with 7mm but they went to 8mm for production.

 

[codytrucker]

I've always thought as soon as they saw the Germans 8X33 cartridge they should of shortened the .30 Remington and reworked the M1 carbine to use the longer round and issued it to the Marines . Considering how fast they got the carbine into service and as many as they made it should of been doable . And a 6 1/2 pound intermediate round carbine would of served well over the next 20 or 30 years after WWII .

 

[gpb]

they should of shortened the .30 Remington

Sounds like the 6.8 SPC.

 

[Steel Horse Rider]

You can bust on the .30 carbine round all day but I have fired them ((FMJ) through the tailgate of a steel pickup tailgate from a Ruger Super Blackhawk when a .45 round (FMJ) just made a dent.

 

[CoalTrain49]

woulda, coulda, shoulda

As was referenced upstream. I have 44 Inland and it's fine for 200m shooting 18" plates. Not a lot of energy at that range but the main battle rifle was an M-1 Garand anyway. Reference the time frame and not the cartridge.

I guess if you were an infantry dog in ww2 and you felt the need for more horsepower you could find an M-1 Garand.....somewhere.

 

[codytrucker]

Sounds like the 6.8 SPC.

Pretty much . Everything was there to do it if they just had the idea . Maybe just a little more than 7.62X39 , but a 130 grain 7MM .

 

[gpb]

I thought that the original purpose of the M1 carbine and cartridge was to replace the 1911 pistol and 45 ACP cartridge being used by support troops. The carbine and cartridge offered more power and longer range than the 1911 and 45 ACP. The carbine and cartridge were not meant to replace a full-sized rifle and cartridge.

The carbine and cartridge only seemed to fall short when mis-applied. (used in place of a full-sized rifle and cartridge). When used as intended and designed (short range use by support troops in place of a pistol), the carbine and cartridge seemed to have meet the original requirements.

 

[cfullgraf]

I guess if you were an infantry dog in ww2 and you felt the need for more horsepower you could find an M-1 Garand.....somewhere.

I shot with a gentleman for a while that was a forward observer in Europe during WWII. They were issued M1Carbines. My friend felt the carbine was a bit light so he scrounged an M1 Garand. He carried it for a couple months and since he hardly ever fired in anger, he decided the Garand was too heavy. He went back to the carbine.

 

[lemaymiami]

A lot of dead enemy in the Pacific would be the best indicator of that old carbine's worth (or if you want to, remember the NYPD's robbery stakeout team - that used war surplus carbines with soft point ammo to put down armed robbers - in progress, at close quarters when reaction time and quickness of movement was life itself...). That's the measurement I'd apply to whether that design was a good one - for that era....

I think enough of it that it's my primary close quarters vehicle defensive weapon out on the road... Yes, today we have several generations later the AR platform, and the Ruger mini platform - but for its day that "war baby" was just the ticket at relatively close quarters. NO, it was never a main battle rifle -nor was it designed to be...

 

[Speedo66]

I enjoy my WWII Underwood Carbine just as it is.

In this day of pistol caliber carbines, one in .357 magnum would be an interesting conversion, though.

 

[trackskippy]

I enjoy my WWII Underwood Carbine just as it is.

In this day of pistol caliber carbines, one in .357 magnum would be an interesting conversion, though.

Seems like over the years Ive heard a lot of talk of that, but never saw one materialize.

 

[GrumpyOlGuy]

This was posed as a "what if" (coulda) proposition. Just thought this would've been more useful relative to the Garand (10 lbs+).

I modified a couple of carbines a few years ago (new builds, on Fulton Armory receivers): one in a "Short" 300 blackout, the other in a .256 Win Mag rimless. The Short BO used the standard carbine loads. Certainly doable projects. Both theoretically in the 0.275 to 0.300 BC range. (Why? Cuz it was fun for an older person!)

Anyway -- just thought this might have been a real possibility 83 years ago (spitzer-type bullets had been around a long time by then). Maybe it was just the extremely rapid development timeline (as the second poster mentioned). A little tweak, and it's a much more capable weapon.

I do like the original carbine, just fine. Extremely handy weapon - 5.5 lbs. I can hit OK on the nearby 200 yd range (pie-plate of accuracy). I don't know why folks think it won't work out that far. I think the original spec for it was to pierce a steel helmet at 300 yds.

 

[Royboy99]

The M1 Carbine is fine just the way it is. It's a close range personal defense weapon, not a battle rifle. It will never be a battle rifle. It doesn't need to be a battle rifle, we've got plenty of battle rifles to choose from.

In it's role as a close range personal defense weapon, it far outshines any handgun. Never mind that it's "only" a 110 grain 30 caliber round nose bullet. The fact is, the average (typical) user can shoot it with a lot more effect on target than they can a handgun of any kind. Two or three of those "puny, low ballistic coefficient, slow moving, round nose" bullets hitting center mass will do a lot more to settle the immediate conflict than will a whole magazine load of 9mm or .45 bullets flying through the air all around an attacker. It will also outperform the 8 - 10 pound battle rifle that remained slung across your back because it was so big and heavy and slow and clumsy to deploy.

If you need a fairly small, light rifle to shoot pointy bullets, get an AR, that's what they're made for.

 

[kanook]

Here is an original proof load

 

[Jim Watson]

Back when the DCM turned loose a lot of Carbines through NRA at low prices, there was a lot of wildcatting done.
There was the .30 Kurtz which was a '06 cut and necked to Carbine length, lots more chamber volume. The bolt face had to be opened up but fortuitously the 15 shot GI magazine would hold 7 Kurtz.

One guy took it a step further and put in a .375" tube, mono blocked into the rear section of the carbine barrel. He fed shortened '06 cases into a .38-40 sizing die. The thick unreamed case neck would hold a .375" bullet. He loaded it up to .35 Remington ballistics.
I never saw any followup, I wonder how the Carbine action held up to these bigger rounds.

Gunsmith John Lawson put a .224" barrel in one for his daughter, chambered it for .221 Fireball, and loaded it with blunt Hornet and Bee bullets to fit the magazine.