5.7 Johnson and M1 Carbine

[eb in oregon]

5.7 Johnson firearms and reloading supplies are still available, but rare. Only about 200 original Johnson "Spitfire" carbines were made by Melvin Johnson's son's. The market to convert rifles never panned out and the cartridge never caught on. It was before it's time. CH4D makes reloading dies and case forming dies. You'd have to contact them about current price and delivery date.

There is an IAI 5.7MMJ being offered on Gunbroker, but the company (or guy) want's more than twice what it's worth (IMHO), so it won't sell anytime soon. Iver Johnson made a few, but the quality of those carbines (as well as IAI) is suspect. There were issues with both manufacturers regarding barrel twist and quality control. It's not a straight forward conversion. The feed ramp of the .30 Carbine receiver needs to be modified and if done incorrectly your receiver is ruined and it won't feed properly. Then too the twist rate of the original 5.7MMJ Carbine was 1/16 and the others have a faster twist rate which doesn't stabilize 40 grain projectiles well, which is about the heaviest bullet that the cartridge was designed to handle. Wikipedia's information is incorrect in that regard as Ed Johnson himself has stated that the twist rate was 1/16 for Johnson's Carbines and it was originally designed for 40 grain projectiles, 50 grain at the absolute maximum.

Forums - Johnson Rifle Site Bulletin Board

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[Trooperdan]

5.7 Johnson firearms and reloading supplies are still available, but rare. Only about 200 original Johnson "Spitfire" carbines were made by Melvin Johnson's son's. The market to convert rifles never panned out and the cartridge never caught on. It was before it's time. CH4D makes reloading dies and case forming dies. You'd have to contact them about current price and delivery date.

There is an IAI 5.7MMJ being offered on Gunbroker, but the company (or guy) want's more than twice what it's worth (IMHO), so it won't sell anytime soon. Iver Johnson made a few, but the quality of those carbines (as well as IAI) is suspect. There were issues with both manufacturers regarding barrel twist and quality control. It's not a straight forward conversion. The feed ramp of the .30 Carbine receiver needs to be modified and if done incorrectly your receiver is ruined and it won't feed properly. Then too the twist rate of the original 5.7MMJ Carbine was 1/16 and the others have a faster twist rate which doesn't stabilize 40 grain projectiles well, which is about the heaviest bullet that the cartridge was designed to handle. Wikipedia's information is incorrect in that regard as Ed Johnson himself has stated that the twist rate was 1/16 for Johnson's Carbines and it was originally designed for 40 grain projectiles, 50 grain at the absolute maximum.

Forums - Johnson Rifle Site Bulletin Board

Eric, is the Johnson Forum active? I have tried to log in there but haven't been able to. I have one of the original 5.7 Johnson built carbines.

[eb in oregon]

is the Johnson Forum active? I have tried to log in there but haven't been able to. I have one of the original 5.7 Johnson built carbines.

It is. If you're having difficulties registering see if you can PM Ed Johnson.

http://www.johnsonautomatics.com/