5.7 Johnson and M1 Carbine

[eb in oregon]

I just found this forum yesterday when searching 5.7 Johnson (5.7 MMJ and .22 Spitfire) and found the thread below fascinating. However it was requested I not revive a thread years old. So here is a new one regarding the same subject.

First, the 5.7 MMJ was designed by Melvin Johnson for a 40 grain bullet, 50 grain maximum. The 30 Carbine case is just a bit small to get the full potential from a 55 grain bullet. It was loaded originally with 12.5 grains of 4227 powder, 40 grain soft nosed bullet (.22 Hornet), to about 2800 fps, with a 1/16 twist. This information comes from Ed Johnson, Melvin's youngest son, and who actually tried to bring that project to fruition after Melvin died. He can be found on "The Johnson Rifle Site" as the sites originator and owner. Ed has stated that they made right around 200 original Johnson Carbines and they actually sold at a loss in order to get the business going. I load the cartridge myself and use either 35 or 40 grain bullets with a charge of 12 grains of H110 for the two and it does pretty well for accuracy and it is a hot little cartridge that is hands over fist better than the FN 5.7x28 and if used in an M2 Carbine is an awesome package.

To build a 5.7 Johnson carbine you need a barrel (made by several different business's after Johnson's company folded due to lack of orders) and to re-profile the feed ramp for the cartridge. The feed ramp is the tricky part as I've never seen a drawing or a decent description of how that's done. Plainfield Machine made some later, as did Iver Johnson, IAI, and Fulton Armory. Unfortunately it never generated enough interest when those company's were making those carbines and that's a shame as it is a tremendous cartridge for the platform it was designed for. Of the carbines manufactured for the 5.7 Johnson obviously the original carbines are the best to have but they are getting as rare as fangs on a chicken. I've heard the Fulton Armory carbines were of good quality but have never seen one. The IAI and Iver Johnson had quality problems, which is the primary reason they weren't so successful. I've an original Johnson and an IAI carbine, the Johnson is of a higher quality though it used an aluminum cast trigger housing that Ed Johnson sourced from Plainfield Machine. It was due to the collapse of Johnson that Plainfield even started making M1 Carbines in the first place. A stock of unsold parts destined for others.

It has been claimed that the government bought some Plainfield carbines for use by security contractors, however I find that hard to believe as the federal government has huge stocks of M1 Carbines in storage and has been receiving them back for years from foreign country's that were given some later, it makes little sense to buy more from an upstart and new company. I don't know how some of those receivers ended up at the CMP but they were never in service with our military. Anyway, the 5.7 Johnson is a good cartridge and it's performance is greater than it's size and weight.

https://www.milsurps.com/newreply.ph...reply&p=266241

https://www.johnsonautomatics.com/

Information

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[browningautorifle]

i thin k this one just got lost in the cracks of time. The cartridge wasn't a success at the time when they had just passed the .30 cal and were trying 7.62, and 5.56 was just looming too. All this and three wars in a short time, over a twenty year period and it was forgotten. I would like to try a carbine in that chamber but they are all but unobtanium here in Canada and a registered trial experiment isn't much fun here, not with our overseers.

[eb in oregon]

i think this one just got lost in the cracks of time. The cartridge wasn't a success at the time when they had just passed the .30 cal and were trying 7.62, and 5.56 was just looming too. All this and three wars in a short time, over a twenty year period and it was forgotten. I would like to try a carbine in that chamber but they are all but unobtanium here in Canada and a registered trial experiment isn't much fun here, not with our overseers.

I'd have to agree with you. It is weird though that in the last 20 to 30 years the firearms industry has created many new small caliber cartridges but the 5.7 Johnson hasn't seen a revival. I believe that if a company would make a new version (especially in stainless steel) it would see a resurgence. As long as people stayed within the parameters of the original design and factory ammunition was available. I would point out though that Ed Johnson has stated in the past one of the reasons the cartridge initially failed was that Johnson had a hard time trying to get anybody to make factory ammunition for it. Those that did didn't make much, so ammunition was a problem. And most people don't want to spent the time and effort to "roll" their own. One of my dreams for years has been an M2 Carbine in 5.7 MMJ. With decent magazines and not that imported rubbish.

Video: 5.7 mm Johnson Spitfire Carbine | American Rifleman | Official Journal Of The NRA

[browningautorifle]

With decent magazines

USGI... I'd just make my own anyway. Probably just gas check cast and as heavy as I could find for a mould.

[tiriaq]

Years go I read an article wherein the author made up a 5.7 on a carbine. He cut the barrel off outboard from the gas block, bored out the stump, and sleeved in a .22 barrel. Did it this way to preserve the slide grooves in the barrel.

[eb in oregon]

Years go I read an article wherein the author made up a 5.7 on a carbine. He cut the barrel off outboard from the gas block, bored out the stump, and sleeved in a .22 barrel. Did it this way to preserve the slide grooves in the barrel.

That individual may have done so when barrels were difficult to come by and I recall once seeing something the same. Conversions of .30 caliber barrels to a smaller caliber by boring out the original barrel and sleeving. And too if the proper twist rate is used I see little difficulty in using a .22 liner. Some liners have thicker walls than others and probably can be used to change caliber.

As for the issue of Plainfield's being used by the US government this might help clear up the picture.

Plainfield Machine Company

[Bruce McAskill]

The government at one point had many hundreds of thousands of carbines in storage. They started giving and selling these as assistance to many friendly governments. Vietnam was the major source of carbines being sent to friendly countries and the South Korea too. Both got many hundreds of thousands of carbine. So many were used that there were none available for use here. Thailand is a prime example of not enough carbines to go around. Contracts with Howa in Japan were made and surplus WW2 equipment was sent to Howa to make carbines. 10,000+ carbines were made and sent to Thailand. Police agencies with in the military had no access to carbines so the next thing was contracts to the likes of Plainfield to supply these needs. These were later sold off as surplus to the militaries needs. But any county that was anti-Communist got carbines.

[eb in oregon]

I have no idea how many carbines Plainfield made, but I'm sure they didn't make their own carbine until Millville Ordnance (a company Plainfield was supplying parts) folded and they were left with a bunch of parts, so Plainfield started making them under their name. I'll also conjecture that any carbines that Plainfield made was a direct response to a contract for other governments purchasing them and our government did no more than rubber stamp the contract and ability to export to those governments. As for Plainfield receivers ending up at the CMP it was more likely that when those firearms were collected from the users that no attention was paid to manufacturer and they were just collected and crated, then returned. I've read nothing that stated or suggested that Plainfield ever had a contract to supply M1 Carbines directly to the US government.

[RCS]

I still have a screwdriver marked Millville Ordnance which they gave you with a large parts order.

I always heard the 5,7mm was 40gr bullet @ 3000 fps and that was published

There was also another carbine wildcat called the 30 Kurtz using a 308 case cut down to 33 mm and necked down
to 30 cal. required a new barrel, never really got off the ground

[Bruce McAskill]

The contracts were made. Many were in armories of base police after military personal no long stood guard duty at the gates to bases. I have seen them there over the years along with M14 rifles. Back in 1991 the M14 rifles were recalled. Went to play in the sand box. Several years later the carbines were taken away and replaced with M16 rifles. A lot of carbines were sent to Capt. Crunch too. Many were put into piles, covered with diesel and sent afire. When the fire was out an M60 tank was used to roll over the pile again and again till nothing was left useable. Just twisted piles of blacked metal.