[Teddy bruckshot]

Hi, does anyone know off the fostech echo trigger is able to drop in the mcx 556? I just ordered a fostech echo trigger and I was wondering if it will fit in my mcx like other ars. Thanks for your help.

 

[MrMcGoo]

Hi, does anyone know off the fostech echo trigger is able to drop in the mcx 556? I just ordered a fostech echo trigger and I was wondering if it will fit in my mcx like other ars. Thanks for your help.

Welcome to the forum.

If your bolt carrier assembly is the new model, aftermarket triggers will not actuate the safety lever and therefore not move the firing pin. Your trigger will drop in, but will probably only work with the original bolt carrier, but not the Gen 2 bolt carrier.

SIG has some recall information on their site for the MCX.

Bill

 

[cole2757]

the fostech comes with its own bolt carrier and wont work without it. the franklin binary might work. it works in some mpxs and not in others. it didnt work in my mpx on semi but ran fine on binary. maybe see if others have had success with the mcx.

 

[Teddy bruckshot]

Hi, does anyone know off the fostech echo trigger is able to drop in the mcx 556? I just ordered a fostech echo trigger and I was wondering if it will fit in my mcx like other ars. Thanks for your help.

Welcome to the forum.

If your bolt carrier assembly is the new model, aftermarket triggers will not actuate the safety lever and therefore not move the firing pin. Your trigger will drop in, but will probably only work with the original bolt carrier, but not the Gen 2 bolt carrier.

SIG has some recall information on their site for the MCX.

Bill

Thanks Bill, I have the gen 1 mcx. So Do you think the echo will work in this model? Or will I have to get it modified?

 

[cotis]

Teddy, your best bet is to try it with your Gen 1 BCG. It will most likely not work with the new BCG unless the hammer has the same dimensions as a mil-spec hammer or a Geissele, which are the two safety bars Sig has designed for the new BCG so far.

I ran a Timney in my gen 1 and it was 100%. Mine is back at Sig getting updated (hopefully not screwed up).

 

[MrMcGoo]

Teddy,

Drop your new trigger in and hope for the best at the range. The primary reason for the recall was related to slam fires on 300 Blackout rounds, so no 300 Blackout barrel should ever be installed with the original BCG. Also, keep an eye on the BCG and trigger condition as the MCX/MPX design seems to be hard on trigger groups and BCGs. Thorough lubrication seems to help as does the low gas setting.

I've put in a POF roller cam pin in my Gen 2 BCG in the hope that the low gas setting will keep my Geissele SSA in good condition. Geissele makes its triggers out of S7 tool steel, but premature wear has been reported in a few instances. Hence, Geissele has stopped recommending their triggers until they design new triggers for the MPX/MCX type weapons.

Bill

 

[cole2757]

the echo uses an AR carrier with a curved part cut out on the bottom. the trigger wont work without it.

 

[jugger]

Thanks Bill, I have the gen 1 mcx. So Do you think the echo will work in this model? Or will I have to get it modified?

Teddy,
Any luck? The new version of the Echo trigger no longer needs a special bolt.