caf1948

Semi-auto Johnson LMG

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I believe at least two of our Website Team members have had this done and/or currently own such modified pieces. If I recall correctly, it could involve the substitution of '41 JSAR components and possibly the receiver with a '41 JLMG stock, rear sight, magazine, fore-stock, barrel & front sight. You would in some fashion eliminate the word "auto" on the selector switch. It would preferably involve a professional gunsmith to make the conversion. Let's see if other folks chime in on this. We've also had a small # of conversions to the prototype "Johnson Auto Carbines" as described in our book.   ej

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To create a 41 JLMG look-a-like from a JLMG parts set, begin with a 41 JSAR receiver and modify it to accept the lower fire control and magazine support assembly.  We are already practically home as the receiver is marked Johnson semi auto rifle!

The fire control is modified as follows: Remove and discard the trip plunger, spring and retainer from the bolt rear.  Grind the retaining holes off the top of the bolt catch support assembly so the assembly (which is discarded) cannot be installed.  Also discard the bolt catch support spring.  Now either weld a pin on the outside of the control group to prevent the change lever from rotating all the way to the left (full auto) or modify the change lever with an appropriate weld to prevent it from rotating into the full auto position.  This makes a neater conversion. 

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On 6/30/2019 at 11:26 AM, Ed Johnson said:

I believe at least two of our Website Team members have had this done and/or currently own such modified pieces. If I recall correctly, it could involve the substitution of '41 JSAR components and possibly the receiver with a '41 JLMG stock, rear sight, magazine, fore-stock, barrel & front sight. You would in some fashion eliminate the word "auto" on the selector switch. It would preferably involve a professional gunsmith to make the conversion. Let's see if other folks chime in on this. We've also had a small # of conversions to the prototype "Johnson Auto Carbines" as described in our book.   ej

I have done just that on some Johnson semi-auto conversions in the past. The lower receiver will require 0.040 removed on the right side, or the depth of the lettering. This is done using a magnetic base surface grinder by a machine shop, or gunsmith licensed to perform the job. The words SAFE and FIRE will need to be engraved in their respective locations using a Hermes Engraver with the correct font and sized exactly as the original lettering. The sear, trigger and other pins will require a lathe to remove 0.040 from the right side and match the amount removed on the receiver. After re-parkerizing the rifle it is impossible to distinguish it from the original. This is the same way my Johnson Auto-Carbine was done and it looks correct in every way. I will have to drag them out and submit a photo.

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