Corn Gunworks Ambidextrous Milspec Active Reset Conversion (MARC) - AMBI-MARC

Compared to other similar products on the market, the lever arm of the MARC is:

This list is not exhaustive, and inclusion on (or omission from) this list does not guarantee compatibility in every possible configuration. There are many variables involved, and it is not feasible to test every combination.

Standard test configurations are as follows:

• Aero Precision Gen 2 Lower / M4E1 Lower
• Standard carbine buffer tube with carbine spring and H2 buffer
• A5 buffer tube with A5 spring and H1 buffer

Additional requirements

• An M16-cut bolt carrier group (BCG) is required
• A low-shelf lower receiver is required, or the user must be comfortable modifying their lower to a low-shelf configuration
• If using a Geissele Trigger, you must have our Geissele Over Travel Stop installed

– Geissele	SSA	Two Stage	YES*
– Geissele	SSA-E	Two Stage	YES*
– Geissele	S3G	Single Stage	YES
– Geissele	SD3G	Single Stage	YES
– Geissele	G2S	Two Stage	YES*
– Geissele	SD-E	Two Stage	YES*
– Geissele	SSAEX	Two Stage	ONLY WITH MODIFICATION YES- DO NOT PURCHASE IF UNWILLING TO MODIFY
– Geissele	SSAX	Two Stage	ONLY WITH MODIFICATION YES- DO NOT PURCHASE IF UNWILLING TO MODIFY
CMMG	Milspec	Single Stage	NO
DPMS	Milspec	Single Stage	NO
Jacob Gray	Jacob Gray Single Stage	Single Stage	YES
MimTac	MimTac Drastic	Single Stage	YES
Noveske	Noveske Single Stage	Single Stage	YES
PSA	PSA EPT	Single Stage	YES
PSA	PSA Custom SS Drop In	Single Stage	YES
Rise Armament	Rave 140	Single Stage	YES
Rise Armament	RA 434	Single Stage	YES
Rise Armament	RA 535	Single Stage	YES
Rise Armament	RA Blitz	Single Stage	YES
Rise Armament	RA LE145	Single Stage	YES
Rise Armament	ICONIC	Two Stage	NO
Schmid Inside	Schmid Two-Stage	Two Stage	ONLY WITH MODIFICATION YES- DO NOT PURCHASE IF UNWILLING TO MODIFY
Schmid Inside	Schmid Pro Line Trigger	Single Stage	YES
Schmid Inside	Schmid Inside GI Flat Face SS	Single Stage	YES
Schmid Inside	Schmid Inside Match Flat Face SS	Single Stage	YES
Smith Defense	AR15 Lower Parts Kit	Single Stage	YES
Sons of Liberty Gun Works	SOLGW LFT	Single Stage	YES
Spikes Tactical	Spikes ST Battle	Single Stage	YES
Timney	Timney Competition 3LB	Single Stage	YES
Timney	Calvin Elite	Single State	YES
Heckler Koch	HK MR556A1 Trigger	Single Stage	NO

 

*Marked Geissele 2-stage triggers may require some amount of polishing or small material removal on the top of the trigger shoe tail. This is due to increased trigger shoe travel associated with 2 the two-stage models and tolerance stacking between various parts interacting. These are general recommendations based on our personal experience. Your experience may vary depending on your rifle.

Tuning Recommendations

Without proper tuning will cause premature wear. We will warranty any that deform regardless (excluding negligent retardation), but at this time we strongly recommend a 10+ oz buffer weight or a captured/hydraulic buffer (the heaviest that is available) with the MARC if you’re planning on running them with a blowback 9mm. For a tuning guide with full explanations, check out the following video from Blowback9 on YouTube. He is a wealth of knowledge for your AR-“SMG”/AR-PCC needs.

In principle, the AMBI MARC operates in a manner similar to other products, but it remains legally and mechanically distinct due to numerous functional, material, and aesthetic improvements. These improvements reflect independent engineering judgment and upgraded material selection, intended to correct what we consider inferior or unreliable implementations found in other products on the market. The MARC design prioritizes durability and long-term reliability. Particularly because, due to the life-saving nature of the systems, they may be utilized in.