EMR-A is a long in development ambidextrous magazine release for .223
and .308 AR receivers, dating back to 2015. After numerous changes to the mag catch geometry and lever
shapes, final design was made into working prototypes in 2017, and
first shown in public at Cola Warrior West III.EMR-A is an ergonomic
ambidextrous magazine release. The placement of its lever is well
thought out to closely mirror the magazine release button on the right
side. The portion immediately below the bolt catch's lower paddle has a
lower profile to avoid interference, heretofore a common drawback of
popular ambidextrous mag catches, it is also left smooth. The serrated
length of the lever is split into a shallow V shaped serrations (80%)
that conform to the curvature of the user's finger, and straight
serrations (20%) that form a natural index point, and provide additional
traction. We refer to the design as Multi-faceted Control Surface, the
difference MCS makes has to be felt to be fully appreciated.
A 10.9lb rated
magazine catch spring is included with each EMR-A. We've long
considered the standard magazine catch spring to be rather weak (rated
at 8.3lb), accidental / unintended mag drops can take place if a user
slings his weapon, and has gear and pouches on the vest. A stiffer mag
catch spring mitigates these risks, thus it is an integral part in the
EMR-A package.
EMR-A's catch is made from
CNC machined 4140 steel and black nitride coated, its lever is 7075
aluminum and Type 3 hard coat anodized. The roll pin has a shear
strength of 800lbs.
The
LP (low profile) mag catch shaft option reduces the mag catch shaft
length by a full revolution, or 0.03. The LP option on the EMR-A (not
available for extended length lever EMR-A) reduces the installed height
of the right hand mag release button, resulting in a right side mag
release button that sits below the mag release fence. This is our
latest step to mitigate accidental / unintended mag drop risks.
The
LP on the EMR-A will not reduce the EMR-C's installed height on an
AR15/M16 to the point where EMR-C doesn't constitute accidental /
unintended mag drop risks. The LP option's shorter mag catch shaft aims
to reduce the installed height of a TDP spec mag release button (such
as our EMR), it isn't a solution for extended mag releases, the
installed height of which would require a drastically shorter shaft to
offset. EMR-C is meant for 7.62mm ARs, even though it works on an AR15 /
M16, we suggest it be relegated to 7.62mm ARs and gaming ARs, not for
defense and duty.
Notes:* EMR-A's lever pivots on the receiver.*
EMR-A needs to be removed before installing / removing the trigger.
EMR-A is installed and removed in the same manner as a factory mag
catch.
* Please wear
eye protection while installing as there's considerable spring tension in the 10.9lb
spring.
Incompatibilities:
* Geissele's Maritime Bolt Catch.
Material from either the top edge of EMR-A's lever, or the bottom edge
of Maritime Bolt Catch's lower paddle may need to be removed for both to
work together. The close proximity of these two control surfaces makes
this combination less than ideal.
* CMC's anti walk pins
* KNS Gen 2 anti-rotation trigger/hammer pins. KNS Gen2 Mod2 and Gen JJ, and Gen ST (Spikes Tactical) are compatible with EMR-A with standard lever, but not with extended lever. Gen2
Mod2's pins connecting bar may require minor fitting on thicker
receivers to create adequate clearance for the EMR-A's lever when
pressed.
* HK 7.62mm AR style rifles, MR762 series.
* Hodge Defense Mod 2 lower receivers.
* Battery assist device levers.*
Receivers with the left side fence around the bolt catch and mag catch,
such as some CMT, Magpul and AR15.com billet receivers. EMR-A requires
the left side of the receiver to more or less adhere to TDP spcs.
* May not be compatible with Seekins SP223 and AR10 B receivers.
* Due to lack of standards for 308 ARs, EMR-A may not work with 80% 308 ARs. 