[razzman1]

Has anyone by any chance tried the Mossberg JMPRO match cassette trigger in the MR556?

 

[mildot]

Anyone running the Franklin Armory Binary trigger and what they think about it? Is it reliable?
Thanks in advance.

 

[Flipz]

Thanks for putting this list together. I have an extra ALG ACT laying around I can use until I save up for something nicer.

 

[tommyPL]

Here's a test of the Wilson Combat TTU-3G releasing firing pin safety on the HK 416:

 

[Coreybridges33]

I have the Timney DH3 Compition trigger in mine and it works great.

 

[DBClyde]

Does anyone know if the geissele mr556 trigger works with the mr556a4 on a milspec lower? Geissele is telling me it wont work with the a4 lower but since I just bought the upper will it work?

 

[dwillHK]

Does anyone know if the geissele mr556 trigger works with the mr556a4 on a milspec lower? Geissele is telling me it wont work with the a4 lower but since I just bought the upper will it work?

The trigger has nothing to do what you’re doing. The issue for you is that you need a hammer without a notch so that it can activate the firing pin safety (or you can remove the firing pin safety). Since you aren’t using an A4 lower, whether or not the Geissele trigger works or not isn’t really an issue. Most likely, the issue with using the Geissele MR556 trigger in an A4 lower has to do with the 45 degree safety.

 

[DBClyde]

The trigger has nothing to do what you’re doing. The issue for you is that you need a hammer without a notch so that it can activate the firing pin safety (or you can remove the firing pin safety). Since you aren’t using an A4 lower, whether or not the Geissele trigger works or not isn’t really an issue. Most likely, the issue with using the Geissele MR556 trigger in an A4 lower has to do with the 45 degree safety.

Gotcha, I have a standard 90 degree mil spec safety on my bcm lower so that trigger should work just fine? I know some people say to use the ALG ACT trigger but I've become a trigger snob in my old age

 

[dwillHK]

Again, it’s not the trigger (the part you put your finger on and that interacts with the safety axle), it’s the hammer that matters. If you have a trigger that works with the safety you have, that’s fine. It’s the hammer that is the issue. When people talk about the Geissele trigger, or ALG trigger, or Larue trigger, etc. they are generally talking about a matched trigger/disconnector/hammer set. You just need a hammer without a notch at the top. Whatever trigger, safety, disconnector you use doesn’t matter, as long as it properly catches and releases the hammer.

 

[DBClyde]

I should have the trigger in a few hours. Is there a way to test the hammer to make sure it works before taking it to the range this weekend? I'm fairly new to this platform since I have only ever owned pistols

 

[Jodi]

You can add the Eratac drop in trigger to the it works list.

 

[Elitheiceman010]

I should have the trigger in a few hours. Is there a way to test the hammer to make sure it works before taking it to the range this weekend? I'm fairly new to this platform since I have only ever owned pistols

Snap caps

 

[lordboogie]

You can add the Eratac drop in trigger to the it works list.

Does it allow you to put on Safe with the hammer dropped?

 

[Jodi]

Does it allow you to put on Safe with the hammer dropped?

No

 

[dragnet]

Seen some mixed reporting on Hiperfire triggers, I've been using a Hiperfire X2S Mod 2 in the MR556A4 and it's been flawless function for over 1500 rounds so far, no light primer strikes.

I also talked with Hiperfire support over the phone and they say their hammers are based on mil spec profiles for full compatibility. They specifically called out the HK416 and MCX Virtus/Rattler as having been tested to ensure full function with the firing pin safeties. They did say the heavier hammer springs may be required in some scenarios to ensure reliability on harder primers, those are the ones I'm using and have been having full function.

 

[HKNer]

Again, it’s not the trigger (the part you put your finger on and that interacts with the safety axle), it’s the hammer that matters. If you have a trigger that works with the safety you have, that’s fine. It’s the hammer that is the issue. When people talk about the Geissele trigger, or ALG trigger, or Larue trigger, etc. they are generally talking about a matched trigger/disconnector/hammer set. You just need a hammer without a notch at the top. Whatever trigger, safety, disconnector you use doesn’t matter, as long as it properly catches and releases the hammer.

Hey brother I’m having the same issue I have the new A4 MR556 upper I just bought a police trade in 416D upper in the gun won’t even fire but with a milspec lower it work perfectly fine can you help me pleaseee I need recommendations

I should have the trigger in a few hours. Is there a way to test the hammer to make sure it works before taking it to the range this weekend? I'm fairly new to this platform since I have only ever owned pistols

Did the trigger work for you

 

[binbui46]

Does it matter on the atc ar a gold trigger I get? The hammer does look a little different on the adjustable and fixed hammer thanks

 

[binbui46]

hello, is this one adjustable or fixed ?

 

[Sean K.]

Apologies. Posted before I realized the forum took me to the last page. Feel free to delete, mods.