When installing the Adjustable gas block you will need to remove the free float rail handguard. You will also need to remove the original gas block. If you can't find soft jaws or non-mar jaws for your vice here is an easy way to make some. Magnetic tape can be purchased at Walmart although I don't support Walmart as they have partnered with anti gun organizations and are clearing their inventory of ammunition. If you have some scrap plywood your set. Cut the plywood scrap to width of your vice jaws and attach the magnetic strip.
Sometimes the Crunch washer deforms in an unfavorable way that causes it to not want to slide off. This is where you apply oil to he threads and use a vice gripe to slowly cut threads into the crunch washer. The crunch washer is made of a softer material and will not damage the treads of the barrel. Take your time and slowly work it off.
As you can see the barrel threads cut threads into the washer
Original Gas block removed.
This is a comparison between the Seekins Adjustable and the original Micro Gas block.
Notice the gas passage and the set screw going through it. This is what our will be doing to change gas pressure coming through the gas tube. Closing the whole will allow for less recoil. Proper adjustment of pressure is when you find the sweet spot of just having enough pressure to cycle the action no more excess pressure.
To separate the gas tube you need to drive out the roll pin. Here I will make make block to support the gas block out of scrap plywood. Us the old gas block to trace material out you want to remove.
Use a Dremel and a sanding wheel bit to remove material.
Find the hole and drill to have a pin catch.
Use tape to make a depth gauge for your drill bit.
after pin is removed install gas tube into the Seekins adjustable gas block
Install the gas block and tube back onto the barrel use blue Loctite on the set screws to anchor to barrel torque to 25 inch lbs.
Install the Muzzle brake with a new crunch washer. torque till 20 ft lbs then index it from there. Be sure to use a drop of blue Loctite. Leaving the free float rail off go to the range and adjust the gas pressure to desired state. Once you found the sweet stop set the set screw to lock it in and reassemble rifle's free float rail.
AR 15 without the rail looks like something from Star Wars. lol
Tuning at the range. The goal is to reduce gas pressure to the minimum amount required to not only cycle the action, but also lock back the bolt on an empty mag.
These are tuning shots free hand unsupported standing and shooting at target 30 ft away at Gander Outdoor's indoor range. When tuning find the slowest moving ammo you can find. I Used Hornady Black 223 62 gr to tune 3100 ft per sec. Then test other brands to verify function. Using a slower round will ensure reliability for more common off the shelf rounds that shoot hotter and faster.
After dialing everything in reassemble rail torque to 24 inch lbs and use blue Loctite
Bro gets his rifle back before Christmas.
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