LaRue MBT Trigger Install Questions

[Whalstib]

Hi,

On my previous AR I investigated and watched videos of the install and figured I could pull it off. Store I bought it from was slow that morning and offered to do it for me so I let them and watched. They seemed to struggle more than in the videos and I'm curious if any pitfalls they were unaware off that made it more difficult than the smooth YT vids I've seen?

Also...

When discussing mil-spec v. after market triggers at a local shop the counter guy suggested the mil-spec "better" as a heavier hammer drop and some after market triggers can be prone to light strikes.

Is this so?

Any problems with Larue having such issues?

I assume the heavier trigger spring has NOTHING to do with hammer strike force and simply sear release weight so no advantage to using the heavier option trigger...right?

I would think a properly lubed AR with proper firing pin should have no problem with this and perhaps this from battle conditions of MANY rounds without cleaning and perhaps a heavier pin strike to overcome any carbon build up in short term.... I dunno...

Thanks!

W

[CPM]

Hi,

On my previous AR I investigated and watched videos of the install and figured I could pull it off. Store I bought it from was slow that morning and offered to do it for me so I let them and watched. They seemed to struggle more than in the videos and I'm curious if any pitfalls they were unaware off that made it more difficult than the smooth YT vids I've seen?

Also...

When discussing mil-spec v. after market triggers at a local shop the counter guy suggested the mil-spec "better" as a heavier hammer drop and some after market triggers can be prone to light strikes.

Is this so?

Any problems with Larue having such issues?

I assume the heavier trigger spring has NOTHING to do with hammer strike force and simply sear release weight so no advantage to using the heavier option trigger...right?

I would think a properly lubed AR with proper firing pin should have no problem with this and perhaps this from battle conditions of MANY rounds without cleaning and perhaps a heavier pin strike to overcome any carbon build up in short term.... I dunno...

Thanks!

W

You can have an aftermarket trigger and a standard hammer spring. I have two MBT's. Zero light strikes. I use the heavier spring. The lighter one has a soft reset.

The trigger is wide and the inner workings long. I've found I need to remove the safety to get it to seat. That's all. If you're asking this question the risk of carbon buildup to the point of it affecting your gun is exceedingly low.

[1168]

Triggers are not hard to install, but people do eff it up. The LaRue is easier than average, but the guy probably hadn’t touched one in a while or something.

It is true that some triggers can cause light strikes, because of how they arrive at their pull weights and feel. Your LaRue should be just fine, as would be many other well-established aftermarket “tactical” triggers that get discussed here.

You are correct that the heavier trigger spring that comes with the LaRue has no impact on hammer fall energy. I use it because I like the “feel” better, particularly the reset that some people complain about. I also tend to prefer the heavier springs with any aftermarket trigger that has options, so maybe I’m weird.



Hi,

On my previous AR I investigated and watched videos of the install and figured I could pull it off. Store I bought it from was slow that morning and offered to do it for me so I let them and watched. They seemed to struggle more than in the videos and I'm curious if any pitfalls they were unaware off that made it more difficult than the smooth YT vids I've seen?

Also...

When discussing mil-spec v. after market triggers at a local shop the counter guy suggested the mil-spec "better" as a heavier hammer drop and some after market triggers can be prone to light strikes.

Is this so?

Any problems with Larue having such issues?

I assume the heavier trigger spring has NOTHING to do with hammer strike force and simply sear release weight so no advantage to using the heavier option trigger...right?

I would think a properly lubed AR with proper firing pin should have no problem with this and perhaps this from battle conditions of MANY rounds without cleaning and perhaps a heavier pin strike to overcome any carbon build up in short term.... I dunno...

Thanks!

W

[AndyLate]

I also remove the safety to install the MBTs and they are marginally easier to install than a Mil-type trigger because the disconnector is pinned. I always struggle with installing the hammer because you have to fight the hammer spring tension.

Andy

[1168]

I also remove the safety to install the MBTs and they are marginally easier to install than a Mil-type trigger because the disconnector is pinned. I always struggle with installing the hammer because you have to fight the hammer spring tension.

Andy
Run a punch through it before messing with the pin.

[pag23]

Used the Geiselle trigger fitting pin to help install...

[m4luvr]

i believe the store you used is inexperienced and misinformed

[matemike]

AR triggers. Mil spec and the MBT’s are about the same level of difficulty to me. I have used the lighter spring FWIW.

If the shop offered to do it they should be competent. If they had trouble it seems they are somewhat incompetent in that simple task. Does the trigger function correctly?

[Whalstib]

AR triggers. Mil spec and the MBT’s are about the same level of difficulty to me. I have used the lighter spring FWIW.

If the shop offered to do it they should be competent. If they had trouble it seems they are somewhat incompetent in that simple task. Does the trigger function correctly?

I wouldn't say trouble but there was something that took a couple tries to get. Guy seemed a hand short was all. I didn't mean to say he messed it up. It's just I watched a few videos and those guys make it seem extremely easy compared.

I thought maybe a common tough spot that those guys who do lots make look easier.

I shot 100 flawless rounds through it!

Waiting for a new one for my new one!

Thanks!

[Whalstib]

i believe the store you used is inexperienced and misinformed

It was two different stores. The one where I bought and had installed the first trigger months ago is a great shop! The owner took lots of time and broke out some ARs with similar triggers and weights for me to try. His helper who seems quite competent did the install. He's a hardened Army sergeant with lots of field experience..

Second store who suggested light strikes was in response to my remarking why mil-specs are always lacking and my griping of why Daniel Defense puts such triggers in their ARs. I don't think he was quoting gospel with the light strike remark but just what he kinda figured. Another great shop I've done lots of business with.

Even though anonymous I don't like making it sound like guys are inexperienced and misinformed based upon my choice of words.

Thanks

[m4luvr]

Mike’s tool and the KNS Precision, Inc. AR15 Hammer/Trigger Pin Assembly Guide seem to work well for me

[AndyLate]

Perhaps struggle is too strong a word. AR triggers drop right in but the hammers have to be rotated against fairly stiff springs and can move in 4 directions.

Nonetheless, a person who installs triggers/hammers more than a couple times a year should only take a few minutes to swap one.

Hard to compare against videos. The guy or gal doing the video may have practiced once or twice before filming.

Andy

[1_click_off]

I have 6 of those triggers and never an issue. I even put one in a M&P 15/22. You made a good choice. Are there better triggers out there, sure. Are there better triggers for the money, I don’t feel there is. (With that said, I haven’t tried a Centurion Arms yet.....)

[Alex V]

Never had a light primer strike with an MBT and I don't use the heavier spring.

Also, never had a problem installing the two I have. I'm guessing the guy at the counters just hadn't done it in a while... or ever...

[202]

I have two of the 2 Stage Larue triggers. The newest one has only about 200 rounds through it, but never a problem with them. Well built and smooth triggers.

[titsonritz]

Run a punch through it before messing with the pin.

Slave pin.

[Warp]

It varies. I've done some trigger installs in my time now. I put a lower together just recently, maybe a couple weeks ago, easy as pie straight through from memory and felt like it took 10 minutes for the whole thing.

Then yesterday I simply swapped the trigger on an existing lower and damn if it didn't take me about half an hour and a lot of swearing to get it done.

One thing I learned: If you already have a Geissele maritime bolt catch installed, you can't use a slave pin nor can you run a punch through from the opposite side, because the bolt catch blocks the punch or pin from having a straight shot.

Another thing I learned: My bench is far too cluttered because as soon as I drop the pin, I can't find it and have to start dumping out boxes and cans from under the bench to see which one it went into and buries itself.

Getting the hammer pin through cleanly can be frustrating and you may find yourself wishing you did, in fact, have 3 hands. Use a slave pin or punch from the other side, you don't want to be trying to fight the hammer's spring tension entirely with your thumb while trying to line it up and then push the pin through. And don't compare to YouTube videos, those folks made those videos and they are popular enough that the search algorithm gave them to you for a reason (they are often very good at it). Also, it's pretty easy to do many takes and only use the good one, it's also common for guys to cut the video briefly to do what they just explained "because it's hard to do it in camera shot" so there's no telling how long they took.


Also, that LaRue trigger is a winner. If it's installed correctly (look up the correct hammer spring orientation and look into your lower to make sure yours is correct), you won't have any primer strike issues whatsoever.

[titsonritz]

It varies. I've done some trigger installs in my time now. I put a lower together just recently, maybe a couple weeks ago, easy as pie straight through from memory and felt like it took 10 minutes for the whole thing.

Then yesterday I simply swapped the trigger on an existing lower and damn if it didn't take me about half an hour and a lot of swearing to get it done.

One thing I learned: If you already have a Geissele maritime bolt catch installed, you can't use a slave pin nor can you run a punch through from the opposite side, because the bolt catch blocks the punch or pin from having a straight shot.

Another thing I learned: My bench is far too cluttered because as soon as I drop the pin, I can't find it and have to start dumping out boxes and cans from under the bench to see which one it went into and buries itself.

Getting the hammer pin through cleanly can be frustrating and you may find yourself wishing you did, in fact, have 3 hands. Use a slave pin or punch from the other side, you don't want to be trying to fight the hammer's spring tension entirely with your thumb while trying to line it up and then push the pin through. And don't compare to YouTube videos, those folks made those videos and they are popular enough that the search algorithm gave them to you for a reason (they are often very good at it). Also, it's pretty easy to do many takes and only use the good one, it's also common for guys to cut the video briefly to do what they just explained "because it's hard to do it in camera shot" so there's no telling how long they took.


Also, that LaRue trigger is a winner. If it's installed correctly (look up the correct hammer spring orientation and look into your lower to make sure yours is correct), you won't have any primer strike issues whatsoever.

The slave pin is for holding the trigger and disconnector assembly together, the Maritime bolt catch does not interfere with the trigger pin hole. A slave pin does nothing for you at the hammer pin hole. There you cock the hammer and align with your pin punch, remove pin punch while holding the hammer with thumb and insert hammer pin.

Also, there is no reason to remove the safety with a proper trigger.

[AndyLate]

The MBT disconnector is semi-permanently attached to the trigger - no slave pin needed.

On a Mil Spec design trigger (and G trigger) there is no need to remove the safety. On the MBT, the safety normally needs to be removed.

Andy

[Warp]

The slave pin is for holding the trigger and disconnector assembly together, the Maritime bolt catch does not interfere with the trigger pin hole. A slave pin does nothing for you at the hammer pin hole. There you cock the hammer and align with your pin punch, remove pin punch while holding the hammer with thumb and insert hammer pin.

Also, there is no reason to remove the safety with a proper trigger.

Lining up with the punch, then removing the punch, then inserting the hammer pin, is a good strategy, when it works. I've had it work. I've had it not work, just a little movement in doing that and suddenly things aren't aligned any more. If you're good, that's probably the fastest.

I rather run the punch through from the backside to keep that lined up, and then push the pin through following the punch as I back the punch up. That way is easier for me. When doing so is not blocked.

The bright shiny sliver slave pin helps me with the hammer pin install, usually doing it that way is the easiest for me, not punch required, just look for the shiny and you're lined up, push the pin through.

There's more than one way to do it, and some of those ways are interfered with when you have an oversize bolt catch in the way. This I recently learned.

[Curlew]

I find these tapered pins from KNS to be helpful for getting everything lined up:

https://www.knsprecisioninc.com/product/kns-precision-inc-ar15-hammer-trigger-pin-assembly-guide/

[Wow]

I would not spend money on a tool that helps you install the pins. I'd rather spend money on a punch that can be used for more than just that.