KAC Triple Tap. It is a .gov item only right now, they are frighfully expensive to build, and thus expensive to buy.
Initally was from the SR25 BattleRifle, and designed as a control item, then scaled into 5.56mm as a sacrificial baffle to designed to enhance the life of suppressors.
Its a great setup, but unless we can descrease the cost of manufacture - I don't see a large public market.
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