ACOG Maintenance

The Trijicon Advanced Combat Optical Gunsight, also known in the Army and Marine Corps as the M150 Rifle Combat Optic, is a durable and trustworthy optic. However, there are a couple of ways to ensure that this piece of equipment is kept working to standard. The Mount Often times the ACOG will be mounted with a TA51 mount to a 1913 Picatinny rail on either a M4/ M16 or a M249 and the parts of the mount need to be tight. The base of the ACOG is critical for ensuring the optic stays tight inside the housing.

If loose, the optic will move forward and back during operation. It is especially critical to check for looseness if mounted on a M249 due to heavy recoil. If it is, apply a drop of blue Loctite to the two base screws and use a screwdriver to tighten until snug. For military-issue equipment the only authorized Trijicon’s ACOG is the most common magnifying optic in the United States military inventory. compound is Sealing Compound (Loctite), 2 Type and N Grade Blue Thread Locking Compound.

The front of the base should be in line with the front of the locking interface. To properly secure the interface to the rail, ensure that the locking studs are actually in a rail slot and that the interface clamp is not tilted but securely laying on the edge of the rail. Note, it is possible to mount it with the locking bar sideways. While applying forward pressure on the optic, tighten to finger pressure only, then use a screwdriver to tighten a quarter of a turn more. Do not overtighten.

If your optic is not maintaining a zero, a loose mount and proper mounting is the first thing to check. Verify both housing screws and locking knobs. Return to Zero Although the TA51 mount does not have a return to zero knob, there are ways around that to ensure Far

screws and interface. This will allow you to tighten the optic back on to the same tightness after returning it to the correct slot after removal which is critical to maintaining zero. Fiber Optic Light Collector The fiber optic light collector on top of the ACOG is filled with tritium that collects ambient light, allowing the reticle to be brighter. Many times during daylight hours operators will put tape over the light collector to dim the brightness and allow a more crisp reticle.

However, doing this can cause damage to the glass from the tape residue. If you want to dim the reticle and prevent the ACOG is mounted back to the previous zero set. To do this, after gaining a proper zero, use a paint pen to mark which rail slot the optic is in and mark the locking blooming, put apiece of paper under the tape to keep any residue off the glass. Do not attempt to scrape anything off of the glass. If the light collector is damaged it could allow tritium to leak which is very dangerous.

It also deadlines the ACOG if the collector is so badly damaged that it no longer collects light. To check for operation, go into a dark room and see if the reticle is still illuminated. Operator Inspection These easy inspections and maintenance techniques will ensure that your equipment remains in service for as long as possible and can be done by all levels of experience. You are responsible for your pieces of equipment and good practices like these will ensure that no negligence is found. AG