Firing pin protrusion *SOLVED*

[Alex 0]

Hello folks, 

 

I've got a question for y'all about the firing pin and the way it's supposed to fit. I pulled my JSAR apart for a proper deep cleaning for the first time since I bought it around 2018 (Got it from a nice guy in the CA North/East Bay Area who had several - including at least one directly from the estate of Melvin Johnson himself) and had some questions upon reassembly. See the attachments. The firing pin disk won't press flat against the locking cam unit because the "tail" of the firing pin spring is in the way. I didn't see if this is the way it was when I pulled it apart. This also means the firing pin protrudes from the bolt when it's closed and locked. Is this normal, and if not, what's the solution? I'm concerned about possible slam firing, or out-of-battery unpleasantness. This rifle won't have ammo anywhere near it until I'm convinced it's safe. Thanks for any thoughts you can provide!

 

Other issues I encountered were that the rear cross pin is extremely tight, requiring a screwdriver to lever it out, and a mallet/punch to tap back into place. That's different from most of the videos I've seen. Also, when I try to slide the bolt in with the stock fully assembled, it hits and lifts the bolt catch assembly, and won't go in any further. To reassemble, I had to slide the bolt in before putting the buttstock back on. Am I missing something here, or doing something wrong?  

Edited September 25, 2023 by Alex
Question answered

[matconcrete 0]

You are correct to Expect slamfire, if you have another firing pin compare it, I have found one to be too long and also had the washer come loose from the grove and the result was slam fire. 
Phil

[eb in oregon 0]

The object of the spring is to keep the firing pin away from the primer until the hammer strikes it. If the firing pin sticks out I'd conclude the spring was incorrectly installed. Especially if it wasn't like that before you disassembled the rifle. If force is required to put it together something is in the wrong place.

[ArtR 0]

A while back, I had asked for, and received, some fairly good photos of firing pins. From two of the HD photos (expandable) it appears that you firing pin is correctly assembled, as it sort of shows the spring tail going through the disc (which holds the spring in place). My concern becomes, is your spring too short or weakened, not allowing it to push back as intended? Also, is the tail of the spring too long, causing a problem? Or, is the 'disc' damaged/misshaped not allowing proper placement?

[Alex 0]

Not knowing exactly how flush the firing pin should sit against the locking cam unit, that's a hard question to answer. Not having any other firing pins either, I have nothing to compare with. 

 

When the whole bolt is assembled, twisted and "locked" the firing pin won't retract any further than shown even when pressed on, so spring strength isn't relevant to this issue.

 

Maybe I just need to rotate the spring clockwise a bit to make the tail lie flatter...? 

[camstuff 0]

I would check inside the cam to make sure there are no obstructions inside blocking the firing pin. Perhaps post a picture of the other end of the firing pin while it’s inside the cam so I can see how it rests.     I do believe all my firing pin springs are bent flat against the washer.  There is also a couple of notches on the firing pin where the washer should be crimped at the notches, and I believe you won’t see the notches if it’s crimped in the correct location.  I’m away from home right now so I can’t look at my parts for reference just yet. 

[Dutch2 0]

I took mine apart for comparison, the tail of the spring protrudes from the disc just a small amount and is bent inward, and since it is in the groove it slides right into the hole leaving the disc flat against the housing.

I measured my spring, which I got from Numrich  years ago since the one the rifle came with did not look that great.

length : 18 mm, wire diam. 0.7 mm , 4 windings., sorry for the metric measurements, I'm from Holland and grew up with the metric system.

Another thing that comes to mind, is the retaining  collar in the back present and not binding, also in the very back where the firing pin protrudes there is a pivot point for the extension that goes to the main spring, on mine that pivot pin seems to have a relief in it to allow the firing pin to go through it, mine ends up in the wrong place sometimes seeing through the opening you can see the obstruction, swiveling the extension a few times the pin turns and the hole is clear and the firing pin can be inserted.

Putting both halves of the bolt together, the firing pin spring keeps the firing pin retracted until pushed forward, so there you have a few things to check, hope that helps.

I'll leave mine broken down so if you need any more info just let me know.

Best regards,

Herman

[camstuff 0]

I just realized that I forgot to mention the “firing pin stop”. 
 

Alex, Was it in place before you took the pictures of the firing pin protruding from the bolt?  

[ArtR 0]

FYI, from one of the Firing Pin Assembly drawings (77X) (provided to web team members by Ed Johnson)  the instructions are to 'weld or braze in position' the firing pin ring (washer) after assembly and to 'bend' the spring after assembly, as shown at a 30deg angle.

[Alex 0]

Thanks for the replies! I'm now at sea for work until probably mid August, so I'll have to necro this thread when I get home and pull my rifle apart again. 

If there are any JSAR experts around Phoenix AZ or north of there, I'd love to have a second set of eyes on it sometime after I return.

[ArtR 0]

Phoenix, AZ and 'at sea for work'...from 'bone dry' to 'water, water, everywhere'....an interesting change of venue. Keep us posted when you return....stay safe!

[Ed Johnson 0]

Alex, I wish you the best, but thought I should mention that anyone who told you they received a Johnson Rifle direct from the Estate of my father, Melvin M. Johnson, Jr.,, is telling you a "story." I quote the paragraph at the beginning of the Johnson Rifle Message Board by our Webmaster:

" Over the years, certain auction houses or dealers claimed they had "Johnson Estate" items, or "special prototypes" with special serial numbers, available for sale at elevated price levels. These claims should all be considered as outright false. The only Johnson Rifle or deactivated LMG products and prototypes, that were in the personal collection of Melvin Maynard Johnson Jr, at the time of his death in 1965, have been directly handled by members of his family. These items are already in the legal possession of a few private collectors or museums and have never been available for sale to the general public.  "

At the time the above paragraph was written last year, this was still the case. Just recently, some very rare prototypes were actually sold to a private buyer via the Amoskeag Auction House in New Hampshire, but this is the only exception and we have records of those items. .

Some of us are aware of the activities of a certain California arms dealer who, years ago, made claims to have received Johnson weapons from the Johnson Estate. When I confronted this individual, he told me that he had actually purchased these from another dealer who claimed they were from the estate. No paperwork was ever submitted with any of these guns...

If you would like to e-mail me privately, at   edwardrjohnson610@gmail.com   and give me the name of the dealer who made this statement to you, I will confirm whether that was the person I confronted years ago. I am aware that he also sold some Johnson Rifles to other dealers who "bought the story" and then proceeded to sell to buyers.with that story.....but no written proof from the family.    .

[camstuff 0]

11 hours ago, Alex said:

Thanks for the replies! I'm now at sea for work until probably mid August, so I'll have to necro this thread when I get home and pull my rifle apart again. 

If there are any JSAR experts around Phoenix AZ or north of there, I'd love to have a second set of eyes on it sometime after I return.

Alex, I’m in that area.  PM sent- 5-22-22

[Alex 0]

Hello folks! Sorry to resurrect an old thread, but I'm back from sea again for the next few months and looking to figure out what exactly is up with my rifle. 

 

So, I had originally been saying my spring was getting in the way of proper seating of the firing pin; this does not seem to actually be the case. I pushed the spring partially out of its retaining hole, and discovered that the firing pin still wouldn't sit flush, even without the spring interfering. Now I'm really baffled, because I can't see anything else that might begetting in the way. It does this whether the firing pin stop is in place or not. 

 

. 

 

Anybody else experienced anything like this?

 

Also, thank you especially Ed for replying to me and correcting me on the likely provenance of that unusual scoped M1941 I saw. Glad I got the one I did instead. 

 

[ArtR 0]

Alex:

I hope that maybe you and camstuff can possibly hook up and  compare notes.

 

[camstuff 0]

PM’s sent to Alex , 9-9-23

[Alex 0]

So! I know all of you here have been waiting with bated breath to find out how this situation has been resolved. Camstuff came by my place this morning to perform some troubleshooting. He discovered, as tech support people often do, a classic case of PEBKAC (Problem Exists Between Keyboard and Chair). 

 

So, whether or not the firing pin ring/washer sits flush against the locking cam unit appears to actually be irrelevant in my case. Perhaps it normally does sit flush, or is intended to, but in this case it doesn't seem to actually matter so long as it's "close enough"

 

The real issue I believed I had was, in fact, a misunderstanding of how far the bolt can cam when outside the gun versus how much it actually does when it's assembled and in the receiver. Observe the attachments for a demonstration of what had me worried, versus what actually happens inside the gun.

 

To confirm this, I tried loading a spent casing with tape over the primer into the assembled gun to see if the firing pin would indent it. It did not. When Camstuff was here, after checking it out, he reassembled it without the barrel, and we were able to visually confirm that the firing pin does not, in fact, protrude when the bolt is locked in its proper place. As far as we can tell, the gun is perfectly fine. Obviously this makes me very happy! I look forward to taking it to the range again next time I go.

 

Thanks again Camstuff! Please let me know if I missed anything relevant or if you have other thoughts on the matter. 

[ArtR 0]

Alex...sounds like good news all around. Great photos and analysis.  And thanks also to Camstuff for visiting and assisting. Great that the two of you could get together and introduce yourselves.  Good luck at the range and keep us all posted.

[camstuff 0]

I believe Alex drawings did a good job of explaining the issue. I wouldn’t have any concerns firing his JSAR.  
 

Also non of my firing pins seat flush against the cam either.  It was a pleasure meeting you and your collection!  Thank you. 

[M48TANKER 0]

Great drawings. Even I could understand them.