POF USA Roller Cam Pin KIT 223 AR15 AR-15 M16 5.56 or AR10 7.62 (select size)
Cam pin wear is normal for all AR's. It is worse in piston guns do to the alternate operation, and is a result of the cam pin not being fully aligned behind the gas key. In a DI gun, gases inside the bolt carrier, pushing against the ring seals, thrust the bolt forward out of the carrier. This usually assures the bolt is fully extended before the lugs unlock and the complete BCG starts its rearward travel. In a piston gun, only the Bolt Carrier is being pushed back. Once the bolt has rotated and is free of the lugs, the carrier again is free to move rearward. However, in the piston system, the cam pin may or may not have reached its full travel, perfectly aligned behind the piston "gas" key. If not 100% aligned, the hardened square cam pin gouges into the softer aluminum upper, shaving the metal off (often seen as slivers inside the upper). The good news is it will not continue to wear once it gouges out enough clearance where the cam pin sits when the bolt lugs free from the chamber lugs in normal operation.
There are two things you can add to lessen the effect: First, a POF Roller Cam Pin which is round instead of square and rolls onto the portion of the upper where it would normally take chunks out. It will still wear this area a bit, but not nearly as much! Second is the Adams Arms bolt spring if it isn't already installed. This mimics the action in a DI gun where the hot gases push the bolt forward and achieve quicker and more complete cam pin alignment prior to releasing the carrier rearward. I recommend both for all Adams uppers and keeping spare bolt springs to replace after a couple thousand rounds.
This is a MUST HAVE UPGRADE in my book for all AR15 BCG's, but particularly for all piston uppers. This greatly reduces the wear from square cam pins that will create shavings in the upper as square cams create space for themselves. Available as an upgrade kit for Direct Impingement DI with a modified Gas Key.
Reduce friction and drag from the AR platform to stop potential failures. Standard cam pins have a stiff, square, steel head that actually grinds along and wears the inside of the aluminum receiver. POF's NP3 coated roller head actually rotates along the inside wall, enhancing performance, reduces failures and prolongs the life of the receiver. Other carrier and bolt assembly parts not included.
NOW ALSO OFFERED AS CAM PIN ONLY (SELECT KIT TYPE BELOW)
UPC Code: 847313003935
Manufacturer: Patriot Ordnance Factory
Description: Roller Cam Pin Kit 223/AR15
Manufacturer Part #: 00393