Too light trigger pull/reset

[Neil 0]

Hello everyone. 

First post here on the Johnson message board, I was directed here a bit ago to see if someone could help me out with my rifle. 

My Johnson rifle seems to have an extremely light trigger pull/reset. This causes the rifle to bump fire very easily and unexpectedly. 

The best way I can describe this is, if it cycle the action and cock the hammer, pull the trigger and the hammer falls keeping the trigger depressed cycling the action (recocking the hammer) and slowly ease the trigger forward there is very little distance that the trigger travels until it resets and then very slight pressure causes the hammer to fall again. The trigger also seems to be a single stage trigger, instead of the typical two-stage trigger I am used to in '03s, Garands etc.  As I mentioned, this has caused multiple 'double taps' because of this light reset. It happens to me and other experienced shooters.

I have not fired another Johnson so, I do not know if the single stage trigger is normal or if it should be a two stage trigger similar to other military arms. 

So, is there an easy way to fix this issue myself? I know how to field strip the rifle but I do not know about how to take down the trigger group, any assistance in that would be appreciated. 

 

Thank you. 

 

[Joseph Scott 0]

It sounds like someone modified the hammer/trigger sears so as to give full auto by holding back the trigger.  This was common years ago mostly by old veterans who learned it in service.  It is very dangerous.  It takes just a little filing to give this and is hard to see by looking.  I test the trigger group loose in my hand by cocking the hammer back and pulling trigger and holding it back.  Hammer should come up and catch on the secondary sear  If it releases and goes up, sears have been altered.   Hold hammer so you don't get pinched. replacing parts is only solution.

[Neil 0]

Joseph, forgive my ignorance, but is removing the trigger group as easy as pulling the screws infront and behind the trigger and it dropping out?

[Yuccacapt343 0]

Hey Neil,

Welcome! Remove the stock from the receiver. Remove the large head screw under the safety and the second large head screw just behind the magazine. The trigger group/block slides out the top. When you remove the screws, don't loose the washers underneath.

Wayne

 

[Neil 0]

Thanks Wayne, it'll probably be a couple days until I get to pull it apart. 

Are you a fireman? I'm a Captain on a ladder truck

[Yuccacapt343 0]

Neil,

sent you a PM

[Neil 0]

Joesph, 

If I did this test as you described I believe it is not catching on this secondary sear. 

The way I did this test was: removed the stock from the rifle, held the hammer with some pressure and pulled the trigger and let the trigger go. Release pressure from the hammer (which should catch on the secondary sear?) and the hammer does not catch and falls. 

To reiterate the original issue, when the hammer is cocked and the trigger is pulled, the hammer falls. Keeping the trigger depressed and recocking the hammer with the other hand the pressure to release the trigger is about equal to the trigger pull. 

If this is a modified sear issue, are sears available, or am I looking for hens teeth?

[Joseph Scott 0]

I will look to see if I have anything.  Most likely you need the hammer as it was easiest to modify.

[Joseph Scott 0]

I don't have any hammer nor trigger sear bars.  Joe

[Brian Alpert 0]

I have a hammer and sear bar.  Contact me <brian.alpert@louisville.edu>

[Neil 0]

On April 25, 2016 at 7:34 PM, Brian Alpert said:

I have a hammer and sear bar.  Contact me <brian.alpert@louisville.edu>

Email on the way

[Neil 0]

I still seem to be having problems with my rifle and not a strong trigger reset. I've replaced the hammer and sear bar and it's the same problem. It's bad to the point that anyone who shots the rifle to the first time gets a double tap out of it due to the rifle bump firing. 

[Rick S. 0]

Your trigger group (contemporary fire control group) doesn't appear to be the source of your problem - it doesn't sound like you are 'bump firing'.

Check your firing pin assembly! It should have a captive spring that prevents slam fire when the bolt locks into battery. Anything inhibiting proper function of that assembly could cause slam fire to failure to fire conditions. Getting a click when I expect a bang is bad. Pulling the trigger and holding on until the ammo is expended while attempting to grab the charging/operating handle with your trigger hand is the other extreme and infinitely worse, in my opinion. Kinetic energy (mass of the firing pin + velocity of the bolt) must be captured by the spring or you will experience slam fire conditions! A weak, damaged, broken or missing firing pin spring/firing pin spring retainer or damaged firing pin may require replacement - especially if you've replaced the 'buffer spring' or recoil spring in the stock.

There's a delicate balance that has to be maintained in any recoil or blow-back operated weapon as any M1911 fan can testify to.

Since you have to dismount the bolt carrier assembly to inspect your firing pin assembly, you might as well look those components over for anything peculiar: deformation, burring, galling, excessive grease, cosmolene, dirt, etc. Keep in mind these weapons may not have been properly maintained since they were originally assembled. Damage could've occurred so long ago that patina may hide conditions that would be obvious had it occurred yesterday.

For your particular problem, I would look at firing pin protrusion, also. The firing pin hole in the bolt face may be excessively large or deformed, causing the firing pin to get stuck in the bolt face. Sometimes it sticks only when the firing pin is struck by the hammer, but shakes loose when the action is manipulated (the firing pin assembly may still function fine!), making it very easy to overlook. ('Snap caps' prevent this condition when dry firing, by the way.)

I believe your bolt carrier group, particularly the bolt/firing pin assemblies, may be inducing an intermittent slam fire condition. If this is the case, continuing to fire it in this condition may cause it to become a constant slam fire condition, until properly repaired. That could get exponentially expensive. Exercise caution!

I cannot take responsibility for your failures and will not take credit for your success. The very unique and interesting design, history and rarity of the '41 Johnsons mean you are on your own if you want to own and operate a functional JSAR. You will not find a live gunsmith with more JSAR knowledge and experience than some of those on this site. That's where I've gotten mine, including this information. The guys that gave it to me are too damned old to remember, though. (I'm no kid or expert, by the way.) I've owned two functional JSARs and have been a very small part of this community since the mid 90s. I credit that feat to the JSAR website, it's creator Jim Pullen, and all those who continue to return to share their knowledge and experience, in spite of the ravages of fire, flood, hurricanes, volcanoes, life and time. (OK, maybe not volcanoes.)

Use this information well. Be smart. Be safe.

Good luck!

 

Semper Fidelis, Rick S.

[Neil 0]

Good morning Rick, 

Thank you for the well thought out reply, but I'm going to insist that it's the fire control group. If I take the stock off the rifle and use my right hand to operate the trigger and use my left hand to operate (mimicking the action of the bolt) the hammer. When I pull the trigger, the hammer falls, keeping the trigger back and cocking the hammer back again and releasing the trigger forward the pressure to release the trigger is nearly identical to the weight to pull the trigger.

So, I stick with it's a bump fire because if you pull trigger the recoil of the rifle causes it to move enough for the trigger to reset and be pulled again, unintentionally. 

Not trying to toot my own horn saying I'm an amazing shooter, because I'm far from it but I do exercise proper trigger pull/control and it happens to me as well as others. It has happened to my friends that I take shooting who have served in the military (Marines and navy).