Trinity Trigger MP5 3-Position FRT

The Trinity Trigger MP5 3-Position FRT is the build-it-yourself path to MP5 forced reset for an owner who already runs, or plans to run, an AR fire control group inside an MP5-pattern lower. It is not a complete lower like the Mars unit or a drop-in cassette like the Rare Breed FRT-RD3. Trinity is explicit that it requires an AR-15 FCG lower adapted to the MP5 platform and does not function in a stock MP5 lower, so it pairs with an AR-FCG MP5 lower from Leber, AS Designs, or a similar maker rather than dropping into a factory housing.

The kit ships the components that convert that AR-FCG lower to forced reset: a V3 Trip Kit, a trigger, a cam, a lever, a curved detent, and an M16 spacer for lowers with cut shelves. The trigger option is curved, flat, or none if you already own the trigger. The third position on the selector engages forced reset, where the bolt carrier mechanically resets the trigger after each shot and every round still takes its own trigger press. Parts are 4140 heat-treated steel and made in Texas.

Price depends on the trigger option you select, and the entry configuration costs roughly a third of a complete Mars lower or Rare Breed unit. The trade is assembly: you supply or build the AR-FCG lower and install the trip kit yourself. If you want a finished part instead, Trinity also sells complete per-host 3-Position FRT Trigger Housings for the HK SP5, HK SP5K, full-size AP5, AP5-P, and PTR 9K. Trinity does not ship to 18 states or Washington D.C. Verify current federal, state, and local law before purchase.