Lasr month I bought an MP15-22 MOE and stuck about 1000 rounds through it without issue. It ate CCI mini mags, CCI standard, Blazer, Aquila etc without a single failure.

Last week I installed a Jard single stage non-adjustable 3lb trigger (see below for instructions)



I put about 150 rounds through the rifle and had a few light strikes (about 4) and the hammer pin (part 8) kept slipping out of one side of the receiver as the pin keeper (part 9) wasn't seated properly. I took it home and re-seated the pin keeper so that it fit snuggly into place. I also installed a Battle Arms Ambi safety (the one specifically built for the MP15-22).

When I went back to the range the following day I immediately had problems. The hammer would not re-set after firing a shot. The rifle would eject the spent round, chamber a new one, but the hammer had not re-set and so you had to re-cock the rifle to get it to fire again. It would do this once or twice in a mag of CCI standard but the hammer would refuse to re-set at all using the more powerful CCI mini-mags.

I took it home, removed the trigger cleaned and lubed it all and put it back in. I tried again at the next range day but the hammer was still refusing to re-set.

Thinking about what I'd changed since it intially worked with the Jard trigger installed I removed the pin keeper plate and the Battle Arms safety (I ran it without a safety at all), but the hammer still refused to re-set after firing a round off.

I've triple checked that all of the springs are installed the right way. I've checked that the pins are seated correctly and are not moving. I've looked at the grip (which i removed to install the ambi catch) to make sure that the bolt was not interfering with the trigger. I've function checked the action with the upper removed and all looks to be working normally.

I am at a loss as to what could be causing this issue. If the Jard hadn't worked when I first installed it I would probably have given up by now, stuck the original trigger back in and tried the Jard in my AR15 instead. Thing is though that it worked okay when I first installed it (except for the pin keeper not being seated properly and the hammer pin coming out).

One guess remaining is that I might have bent the hammer pin when it came lose; not sure if this would cause an issue with the hammer failing to re-set though. I am trying to get a set of KNS anti-rotation pins (the longer set made for the MP15-22) but they are difficult to get here in the UK as not many people will ship them abroad (Brownells don't appear to have the MP15-22 version in stock).

I have tonight re-installed the original trigger and will test it out on Friday. If the rifle shoots okay then at least I know it's an issue with the Jard trigger and not the pins.

Any thoughts or ideas are welcome as I'm all out!

Is the disconnector properly timed? Take the upper off and thumb the hammer back while holding the trigger fully to the rear. Let go of the hammer. Does the disconnector catch it? Release the trigger. Does the sear catch the hammer or does it fall?

Yup, fully checked, I must have done this about 100 times by now and it works every time, catches the disco then tbe sear perfectly.

I can tell you that the there is little tolerance in the hammer trigger relationship. It must be almost exactly in the correct place or the rifle will not function correctly. Even factory new my pin locations were off ever so slightly which caused the hammer to not fall at all sometimes. I just slightly filed of a little bit on the disconnector and have been good ever since. In your case I would say the disconnector is not catching the hammer or the sear is not engaging. This can be caused by the trigger not in the proper position. Do you have anything that restrict the trigger from moving completely forward or backward?

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15-22 bullpup, "X-terminator"

Try to squeeze the trigger and hold as the hammer falls. Then while still squeezing the trigger cock the hammer and release the trigger. Does it still cock?

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15-22 bullpup, "X-terminator"

In normal firing the trigger would be held to the rear as the hammer re-cocks so this is how you need to check it. The disconnector needs to catch the hammer at this stage and then when you release the trigger the sear engages.

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15-22 bullpup, "X-terminator"

Disco and sear work perfectly every time I function check it. Holding the trigger down I reset the hammer which catches on the disco. When I release the trigger the hammer is then caught by the sear. Pull the trigger again and the hammer is released.

Interesting. Well if it functions correctly every time then it must not be the problem. When a round fires the bolt is blown back which cocks the hammer. If something was stopping the bolt from its full rearward travel it may not be able to cock the hammer. Are the rails that the bolt rides on flat and smooth and does the bolt easily move all the way back?

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15-22 bullpup, "X-terminator"

I have heard of people separating the upper from the lower for cleaning and the bolt has fallen out onto the floor bending the rails.

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15-22 bullpup, "X-terminator"

Bolt is okay, rails are fine too. I pretty much clean and lube it after every visit to the range.

I'll report back after my trip to the range with the standard trigger back in. I'm almost hoping that the problems persist, then I can rule out the trigger as the problem and look at the pins.

This is odd. Trigger works fine and the bolt is fine. This just doesn't make sense. Standing by waiting for the results.

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15-22 bullpup, "X-terminator"

I'm due down the range tonight @ 7pm GMT (About 6hrs time) . I've re-installed the original trigger and will see how I get on, but in the mean time I found this interesting exchange on another forum which seems to mirror my issues (but involves a RRA trigger not a Jard).

This was the response
and then this
Now all of this got me thinking. When I was having my issues I was assuming that the hammer had not re-set as the safety was off and the trigger was pretty solid. When I looked inside the rifle the trigger was not back on the disco BUT I do remember on at least one occasion the hammer coming forward as I opened the rifle up. So maybe the issue is with the disconnector not letting the hammer fall after the first shot is fired? (although it function checked perfectly when I had it open and was manually pulling the trigger back?)

Once I've tested the orginal trigger I'll put the Jard back and try again, paying more attention to see if the trigger is caught up on the disco or if it just isn't re-setting properly. If it is caught on the disco then should I think about filing doen the disco spring a little?

JP has a great video on timing the disconnector.

original_FC_inst2

The disconnector bit starts about halfway through.

Went to the range last night and tried out the original trigger and the Jard trigger again.

The good news is that the original trigger worked perfectly, it shot every type of ammo I tried to use without a single problem.

Bad news was that the Jard still played up. I had previously removed the disco and smoothed out some of the edges I could feel with a whetstone and so I was hoping it might have solved the problem. No luck though, it still failed to reset the hammer on some shots, I've posted a short video of the range trip below.

trigger testing - YouTube

It seems to me that the hammer spring is to hard, which prevents the bolt to push it back enough to engage the disconnector. This happened to me when I tried subsonic ammo. The ammo was not hot enough to push the bolt back. Why don't you try to swap the hammer spring to a weaker one like the OEM spring? I am pretty sure that will work!
Have a nice day
/Elmerviking

Hmmm. Not so sure about that as it seemed to cycle standard CCI a lot better than mini- Mags. I think its a timing issue with the disco.

A weaker hammer spring = possible light strikes. I still believe it is the disconnector. It possibly is just slightly off timing and is why it works sometimes. The trigger is adjustable so I think now would be a good time to learn how to adjust it.

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15-22 bullpup, "X-terminator"

This is a non adjustable trigger according to the pic. I have a Geissele SSA-E trigger and had to use the OEM hammer spring because the Geissele spring was a bit too strong and would not cock the hammer. You will not get light strikes with the OEM hammer spring unless the Jard hammer is much heavier than the S&W hammer, which I doubt. Strange behavior ...can you feel any difference in the creep with the Jard hammer (i.e. Is the engagement not long enough)?
/Elmer

(Will be interesting to know what you find out...let us know)

Oops, sorry wrong trigger.

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15-22 bullpup, "X-terminator"

Yeah- I bought a non-adjustable trigger because I didnt want to have to muck about with settings to get it to work!?!

Okay, next visit to the range will be Wednesday after work. I'll try the Jard trigger with the OEM hammer spring and will post up results.

I have a Jard non-adjustable in my 15-22. My notes of 4/16/13 read as follows:

"Installed the Jard non-adjustable trigger that I took out (of another AR). Much trial and error fitting required to achieve proper letoff release, but I got it where I wanted it to be. Tail of trigger needed to be taken down to allow sufficient trigger movement. Unfortunately at that point it also allows the safety to be put on with the hammer down, which is not right. However this being a .22 practice weapon, it is not a real issue as it might be on a 5.56 serious piece. The safety engages and disengages properly and prevents hammer fall when cocked. Had to cut the 3 pound trigger spring off one coil as it was stacking and preventing full movement. The average of 5 hammer falls on the gauge was 3 pounds, 5.8 ozs. Hammer spring seems a bit light so may have ignition trouble. If so I can swap in a heavier hammer spring."

The above was written 2 years and 700 rounds ago; have had zero problems with the trigger assembly since that time.

My guess is that while the Jard N/A triggers work well in ARs (I have put in several) the firing group well in the polymer reciever S&W 15-22 is just enough different to give some fitting problems. Anyway, the above procedures worked for me and I'm quite happy with the results.

Hope this helps a bit.

I find I like Geisselles better nowadays...

Thankyou for the information, very helpful.

So you cut a coil off of the trigger spring (part 4 of diagram at the top) and modified the tail end of the trigger; any more details on this i,e how much materiel did you take off and from where? I'm guessing that this changed the angle of engagment for the sear and disconnect?

Also found this thread which has some interesting info in (specifically post 26)
light primer strikes with lighter triggers?

i have read light strikes and fitting problems with several

makes of AR triggers fitted into the 1522,due to weaker

hammer springs than the 1522 needs

i did not want to start experimenting with what would or

would not work in my rifle due to as you know,getting hold of

spare bits to try out...........reading on the forum quite a few

are using the CMC drop in unit with no problems,so i have one

on order with a straight trigger and in FDE

keith

I looked at the CMC drop in triggers as well, however the only place that I could find one available here was at MidwayUK and they wanted £240.00 plus shipping (about $400.00 + shipping)

I'm off to the range tonight for another attempt with the Jard. I've polished the rails and hammer face and I've pulled out my 3lb yellow JP spring from my .223 to try as well. Fingers crossed

Just my opinion, but the trigger group is too critical for safely using a firearm to have backyard mechanics doing such adjustments. I even doubt if I would let a gunsmith make these type changes to a factory trigger. He would have to demonstrate he had done this a lot.

If it were me & I couldn't afford a better replacement trigger... I'd stick with the stock one. Last year I tried a Timney drop in & it was safe & didn't cause any of your problems, but I did get a lot of failures. I got rid of it & went with the CMC drop in, and have had zero issues since. The CMC dropped in easier & the hammer hits real hard. I know there are other triggers that work well in the 15-22, so why attempt to remake one that doesn't? Stubborn? Me too, but safety comes first. Not enough money? Been there, but would stick with the factory trigger until I could afford something that improves function & remains completely safe.

Yes, you might be able to come up with an adjustment that works, but how will you ever know how close you are to some safety issue? Might be safe for 5000 rounds but what happens with wear? That would scare me greatly.

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FIDELITAS ET FORTITUDO

your not looking in the right place for the CMC trigger

if mine comes good i will share where its from

keith

as Jim says safety first is a must

before Dunblane i had a Coonan model B .357mag that i used

for speed shooting......i had the safety removed in case i had

foul ups .....but it was frowned upon at the club,it was a

simple fix but to be safe i sent it to york guns for them to sort.

IMO just leave well alone

keith

Tomo2:

Just pulled the 15-22 out to verify what I did with the tail of the trigger. By the "tail" I mean the rear stepped-down portion of the trigger. My Jard was purchased in about 2007 and has only a single such extension, whereas your diagram shows a split double tail. I had previously run that trigger in a Bushmaster AR where it worked ok; but it would engage to the "on" position with the hammer forward. Although it was only a spare rifle I did not care for the chance that it could concievably prevent the bolt from being retracted. The rifle worked normally in all other respects. When I sold it I took out the Jard and reinstalled the original parts. By that time I had already taken a little material off the tail and the trigger kit was no longer returnable anyway.

The original trigger in the 15-22 was acceptable but not ideal. Since I had this spare Jard lying around I decided to try fitting it up to the .22. The main problem I encountered right away was that the aforementioned "tail" contacted the safety's shaft and prevented proper disconnector and sear engagement. At his point I figured I had nothing much to lose and carefully removed some material from the top of the "tail" until I got proper trigger engagement and function. I was also able to set the backlash where I wanted in the process. The cutting of the #4 coil spring was a self-evident step and the last thing I had to do. As I recall I had a JP yellow spring in the gun for a short time, got a few misfires, and went back to stock springs.

I looked into installing a standard metal AR safety and found dimensional differences between it and the stock S&W safety. In addition I also think that the 15-22 trigger group well in general has some other anomalies. I have installed about 5 of these triggers. I did have one that was not quite right and Brownell's replaced it. One additional thing I notice is that your schematic shows a "pin keeper" part #9. I've never seen one of those, and quite frankly don't see the point. My stock Jard pins stay in place just fine as they are. They do appear short as the 15-22 lower is a bit wider than a 5.56 receiver, though.

The other Jards I installed have worked fine in all respects. Considering that everyone and his dog makes ARs and AR parts, it's remarkable that things fit together as well as they do...

My latest venture has been to put a Geiselle G2S into a new AR. I like it very much, so will probably lean that way in the future.

BTW--maybe the term "backyard mechanic", like the term "gunsmith" needs to be examined a bit more carefully. I have seen some remarkably good work done by amateurs, and likewise seen a few guns botched up by the rich and famous.

As Inspector Callahan said, "A man's gotta know his limitations."

Just back from the range.

I tried the Jard trigger again, this time with a yellow JP 3lb hammer spring. I'd also polished the rails that the bolt runs on and the face of the hammer itself. CCI standard ammo seemed to run okay, I shot 100 rounds and had maybe 4 or 5 failures to reset the hammer. It still struggled with CCI minimags and Blazer though.

My last option seems to be to sand down the trigger tail and cut the trigger spring as detailed above. I have for now though reinstalled the original trigger and intend to leave it alone for a while.

I'm lucky in that all the work I do gets checked by a friend of mine who's a full time gunsmith. The trigger seems a pretty simple system to understand, it only has a few moving parts and a couple of springs. That's what makes it so frustrating when it doesn't work!

take it to a gunsmith and see if he has an answer or can do it without issues....all this over and over trial and error seems like more hassle than its worth.

at least you will find out if its the gun, you or whatever

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NeedleFreaks Tattoo

Make sure the gunsmith is qualified to work on AR-style FCGs. Many so-called gunsmiths are nothing more than butchers when it comes to triggers.

Personally, the Jard should be returned to factory condition and proceed from there. Doing spring cutting and filing on trigger parts needs to be left to someone who absolutely knows what they are doing!!!