Unfortunately no, this will not bring a 14.5" barrel to a 16" minimum length. This muzzle device has an OAL of ~1.94" and the industry standard thread length for AR's is ~0.625". (1.94 - 0.625 = 1.315) + 14.5 = 15.81"
Yes this item will fit.
The Griffin Armament Taper Mount Hammer Comp features 1/2x28 TPI and is designed for 5.56 (22cal). The Griffin Armament taper mount muzzle devices interface with the Griffin Armament taper mounted suppressor (RECCE, PALADIN, Sportsman, Optimus). To be compatible with the Optimus 9, the blast baffle must be removed. We do not currently carry a muzzle device that uses 1/2x28 TPI internally and 5/8x24 TPI externally.
The Griffin Armament Taper Mount Hammer Comp features 1/2x28 TPI and is designed for 5.56 (22cal). The Griffin Armament taper mount muzzle devices interface with the Griffin Armament taper mounted suppressor (RECCE, PALADIN, Sportsman, Optimus). To be compatible with the Optimus 9, the blast baffle must be removed.
Yes, it will.