PSA Adjustable Gas Block

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TeleStratMan

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Used this on a 6.5 CM upper build. Works great with no cycling issues, blown primers, or damaged brass.
I simply loosened locking set screw [facing front] and adjusted the Gas Screw [facing right] 2 full turns open from closed. Then tightened locking set screw. Very happy with the results.

Note: I checked it before installation and on my PSA gas block 2 full turns from closed exposed 1/2 of the gas port. This would lead me to believe that the rifle would be over gassed without an adjustable gas block.

https://palmettostatearmory.com/psa-custom-750-diameter-adjustable-gas-block-116001.html

I also drilled-tapped- threaded the forward port where the gas tube is normally roll pinned into position and installed a 4-40 set screw with blue Loctite.
 
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dennishoddy

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Got lucky getting it set right. Good deal.
I've always shut the adjustment screw down until it won't lock open on the last shot, then back it out until it locks open on the last shot reliably, then open it another 1/2 turn. That's always worked for my builds.
 

TeleStratMan

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Your suggestion is excellent for anyone who wants a precise setting.
I was looking for a reliable setting with the adjustment without signs of over pressure. After watching several different Youtube videos on gas block adjustments and most always wound up at 1 3/4 - 2 1/2 turns from closed for the final setting. So starting at 2 turns was logical for me as a starting place. I fired 1 cartridge at a time [3 times] and inspected it for blown or dislocated primers- any bulging in the cartridge or obvious damage and made sure the bolt was locking open.
The rifle cycled properly and smoothly. 2 turns worked good with the 6.5 CM on my particular build.
One reason I chose this method is the hand guard on my particular build would require removal to make precise adjustments. I brought tools to the range in case adjustments were needed.

Note: I've got an idea to have an access opening milled in my hand guard where the adjustment screw is located so hand guard removal is not required to make adjustments. I know several machinists that will do it for no charge. I considered drilling a 7/32" D hole to access the adjustment screw but it would be on the edge of one of the M-LOK slots. The hand guard can be milled so the access matches the M-LOK Slots.
 
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