EMR-A v1 was first introduced in 2017, and production stopped in 2024.
EMR-A v1 was designed at a time when Norgon's Ambi-Catch patent was still valid. We like the Norgon Ambi-Catch mechanism, though it's not without minor issues which EMR-A was designed to fix:
1. The lever is largely protected since it's completely contained in the mag catch slot, which is a good thing, but the short lever can be difficult to press when a fully loaded USGI magazine is inside the mag well.
2. The lever can be short for some users.
EMR-A v1 uses an external lever attached to the mag catch plate, when the lever is pressed, the plate is lifted outward and releases the magazine. EMR-A v1 wasn't the first ambi mag catch to use the design, LWRC and SIG have used it, and continue to use it. The design does pose a drawback, it's sensitive to the lower receiver being out of spec (the receiver must be close to TDP spec, and the mag well can't be too thick), as its external lever effectively stops the mag catch plate from protruding sufficiently into the mag well and engage the magazine, if the receiver is too wide, or the mag well is too thick. Also, the lever isn't spring loaded, on lowers that are thinner than TDP spec, the lever can have movement and have a slight rattle.
When the lower is TDP spec or near TDP spec, EMR-A works wonderfully.
EMR-A v2 uses the Norgon Ambi-Catch mechanism, where the mag release plate itself is the lever and pivots when pressed, and has its own internal spring (we use a Colt spec 4 coil bolt ejector spring). EMR-A v2 is no longer sensitive to lower receiver's adherence to TDP spec (though we think they should be TDP spec regardless), as there isn't an external lever attached to the mag catch plate.
For EMR-A v2's internal spring, we chose the Colt spec 4 coil spring, it's much stiffer than the spring Ambi-Catch, and Ambi-Catch clones use. EMR-A v2's plate/lever extends further back towards the buttstock, this provided us the freedom to make the paddle's size and shape more user friendly, but at the same time, its extra leverage has to be offset lest it becomes easy to press and drop the magazine.
The rearward extension serves multiple purposes:
1. The textured portion of EMR-A v2 is further away from the bolt catch's lower paddle. Close proximity of two control surfaces is best avoided, EMR-A v2's lever is further back than EMR-A v1's, and Norgon Ambi-Catch's.
2. The textured portion isn't confined by the length and height of the mag catch slot on the lower receiver, the paddle can now be made larger with more effective textures.
3. The additional length puts the paddle in a position that's accessible for most users.
EMR-A v2 comes with either a serrated, or dimpled paddle (all angles) texture, there will no longer be an extended version, as EMR-A v2's paddle is already further back than the v1's, it's no longer necessary to extend the lever further. The textured paddle continues to have the multi-contoured design of the v1 lever where 80% of the length has a shallow V shape, and the last 20% being straight, the transition forms a ledge that provides additional traction.
EMR-A v2 uses a stiff Colt spec 4 coil ejector spring to counter balance the mechanical advantage. It requires both a long arc, and a firm press to release the magazine. The 10.9 in lb extra power mag catch spring will continue to be shipped with EMR-A v2, but the mag catch spring no longer has any effect on EMR-A v2, it will only stiffen the right side mag catch press. The stiffer mag catch spring was originally calibrated for use with EMR-A v1, but we like it so much, we made them available separately on our site, the stiffer spring mitigate unintentional mag drops.
EMR-A v1 with ABC/R v3
EMR-A v2 prototype with the latest ABC/R v4, notice the greater distance / separation between the bolt catch's lower paddle and EMR-A v2's textured lever.
EMR-A v2 is scheduled to be released to retail and dealers in 2025.