BreechFace
Member
- Joined
- Mar 2, 2020
- Messages
- 3,542
I don't have an Adams Arms piston kit but some thoughts below:
Did you follow these instructions when fitting the gas block (specifically the measurements I highlighted in red)?
https://adamsarms.net/wp-content/uploads/2020/11/InstallationInstructions-1.pdf
It seems they ship the OP rod in the short stroke piston with the intentions of it needing to be "fit" to the rifle. With setting the gap as detailed below by Adams you will need to pay special attention that the gas port is still lining up; if not it may require removing material off the op rod to get it to within their 0.015-0.025" spec while maintaining centering over the barrel's gas port.
Note 3: It is easier to complete the remainder of the gas block installation if it is tight enough to not move
back and forth (towards or away from the receiver) unless you slightly twist the block from side to side as
you push or pull the gas block. If it moves forward or back without having to twist it, tighten it until it
requires twisting to move.
o. While you continue to hold the carrier in the receiver, work the gas block down towards the receiver
until the space between the end of the sleeve and the back part of the gas block is approximately between
.015” and .025”.
(If you continue to move the gas block down towards the receiver it will start to push the carrier down. The
rod will push on the carrier key, which will move the carrier out of battery away from the barrel extension.
If you push the carrier up into the receiver as you move the block away from the receiver the carrier will
move back into battery. You want to make sure that the carrier is pushed all the way forward against the
barrel extension and the space between the sleeve and the back of the gas block is between .015” and
.025”.)
Barrel Warning: We have experienced situations where barrel manufacturers have cut barrels out of the
commercial Mil-Spec tolerances. If the gas block will not go back far enough to get the .015” to .025” space
on the rod then the barrel might be cut out of the proper tolerance (shoulder cut too far forward). If this is the
case, you can either have the barrel shoulder cut back towards the barrel extension (receiver) or buy a
properly cut barrel.
Did you follow these instructions when fitting the gas block (specifically the measurements I highlighted in red)?
https://adamsarms.net/wp-content/uploads/2020/11/InstallationInstructions-1.pdf
It seems they ship the OP rod in the short stroke piston with the intentions of it needing to be "fit" to the rifle. With setting the gap as detailed below by Adams you will need to pay special attention that the gas port is still lining up; if not it may require removing material off the op rod to get it to within their 0.015-0.025" spec while maintaining centering over the barrel's gas port.
Note 3: It is easier to complete the remainder of the gas block installation if it is tight enough to not move
back and forth (towards or away from the receiver) unless you slightly twist the block from side to side as
you push or pull the gas block. If it moves forward or back without having to twist it, tighten it until it
requires twisting to move.
o. While you continue to hold the carrier in the receiver, work the gas block down towards the receiver
until the space between the end of the sleeve and the back part of the gas block is approximately between
.015” and .025”.
(If you continue to move the gas block down towards the receiver it will start to push the carrier down. The
rod will push on the carrier key, which will move the carrier out of battery away from the barrel extension.
If you push the carrier up into the receiver as you move the block away from the receiver the carrier will
move back into battery. You want to make sure that the carrier is pushed all the way forward against the
barrel extension and the space between the sleeve and the back of the gas block is between .015” and
.025”.)
Barrel Warning: We have experienced situations where barrel manufacturers have cut barrels out of the
commercial Mil-Spec tolerances. If the gas block will not go back far enough to get the .015” to .025” space
on the rod then the barrel might be cut out of the proper tolerance (shoulder cut too far forward). If this is the
case, you can either have the barrel shoulder cut back towards the barrel extension (receiver) or buy a
properly cut barrel.
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