A KAW Valley 3.25" Linear Compensator for .22/.223/5.56mm arrived a few days ago. I bought it to replace a short and small CMMG Zeroed Linear Compensator on my 7.5" barrel AR-15 pistol. Upper is a PSA, and lower was assembled by me with a 17 Design & Mfg. stripped folding lower plus Aero Precision parts and a Geissele 2-stage trigger control group. Brace is a Magpul BSL. My first whack at a DIY AR-15 lower. Removed its "A2" flash suppressor and put the CMMG Zeroed Compensator on, but wanted more as a 7.5" barrel produces a loud and sharp report. The KAW Valley reportedly pushes more of the blast downrange than the CMMG. Photos have lint from using paper towels.
Clamped a portable padded armorer's vise onto the edge of the kitchen counter where there was a deep enough lip to hold it. In the vise is a Magpul BEV Block with the upper receiver assembly pinned into the action end of the block. Magpul's BEV Block has two ends. One is made to hold a lower, locking into the magazine well. The other locks onto an upper with an action plug similar to an action rod that goes into the chamber, a pin that goes through the front takedown lug, and an O-ring plug opposite the action end onto which a bolt carrier with bolt can help lock the upper receiver down. The action end has a metal core that runs from it down through the entire block. Used the lower receiver end to build two pistol lowers starting with stripped lower receivers. I also have a Wheeler Delta Series Upper Receiver Action Block that could have been used, but this one seemed easier as it has the action plug that engages the barrel chamber, and the barrel was going to be subjected to the torque.
This is the CMMG Zeroed Linear Compensator to be removed. It's about the same size as the A2 flash suppressor it replaced. Fortunately its flats are accessible for wrenching it off without having to remove the handguard.
A Knipex smooth jaw pliers wrench adjusted to proper jaw width removed the CMMG and disposable crush washer. The great thing about the Knipex, in addition to smooth jaws, is how it maintains the jaw faces parallel to each other.
The Kaw Valley is hexagonal at 30mm across the flats. A 30mm socket can be used to install it, with some painter's tape around the compensator to protect its finish from being marred by the socket.
One must read directions and follow torque specs on specific muzzle devices. They're not all rated for the military A1 and A2 military maintenance manual torque values. This Kaw Valley has no orientation, and its torque spec is 15 lb-ft without a crush washer. Not all muzzle devices use one. This was easy with a 3/8" drive torque wrench using a 1/2" drive adapter for the socket, compared to the torque typical of buffer tube and barrel castle nuts. Minimum for this wrench is 10 lb-ft., about par for a 3/8" drive torque wrench.
The new KAW Valley linear compensator installed with painter's tape removed.
The complete pistol with its new linear compensator. I may make some upgrades to the PSA upper, but that's a low priority and I need to shoot this one some before considering any.
My next project is building a 10.5" AR-15 pistol upper starting with a stripped upper receiver.
John
Clamped a portable padded armorer's vise onto the edge of the kitchen counter where there was a deep enough lip to hold it. In the vise is a Magpul BEV Block with the upper receiver assembly pinned into the action end of the block. Magpul's BEV Block has two ends. One is made to hold a lower, locking into the magazine well. The other locks onto an upper with an action plug similar to an action rod that goes into the chamber, a pin that goes through the front takedown lug, and an O-ring plug opposite the action end onto which a bolt carrier with bolt can help lock the upper receiver down. The action end has a metal core that runs from it down through the entire block. Used the lower receiver end to build two pistol lowers starting with stripped lower receivers. I also have a Wheeler Delta Series Upper Receiver Action Block that could have been used, but this one seemed easier as it has the action plug that engages the barrel chamber, and the barrel was going to be subjected to the torque.
This is the CMMG Zeroed Linear Compensator to be removed. It's about the same size as the A2 flash suppressor it replaced. Fortunately its flats are accessible for wrenching it off without having to remove the handguard.
A Knipex smooth jaw pliers wrench adjusted to proper jaw width removed the CMMG and disposable crush washer. The great thing about the Knipex, in addition to smooth jaws, is how it maintains the jaw faces parallel to each other.
The Kaw Valley is hexagonal at 30mm across the flats. A 30mm socket can be used to install it, with some painter's tape around the compensator to protect its finish from being marred by the socket.
One must read directions and follow torque specs on specific muzzle devices. They're not all rated for the military A1 and A2 military maintenance manual torque values. This Kaw Valley has no orientation, and its torque spec is 15 lb-ft without a crush washer. Not all muzzle devices use one. This was easy with a 3/8" drive torque wrench using a 1/2" drive adapter for the socket, compared to the torque typical of buffer tube and barrel castle nuts. Minimum for this wrench is 10 lb-ft., about par for a 3/8" drive torque wrench.
The new KAW Valley linear compensator installed with painter's tape removed.
The complete pistol with its new linear compensator. I may make some upgrades to the PSA upper, but that's a low priority and I need to shoot this one some before considering any.
My next project is building a 10.5" AR-15 pistol upper starting with a stripped upper receiver.
John
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