Did anyone ever make an adjustable gas block with an a2 style fsp with four set screws where otherwise the taper pins would be? I got a 1:8 stainless douglass with the four divots and would like a FSP gas block, but would also like for it to be adjustable. I might just say fuck it and dimple the underside for a normal gas block but would rather not. Thanks.
- Thread starter jeffl838
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Yeah, I was looking at that but would rather have a fixed FSP and/or adjustable. Beggars can't be choosers though. I like the four screws from the side design - I always thought it was silly to have grub screws loosen in the direction of gravity.
We install a lot of Mk12 gas blocks with two set screws and Red Loctite. I cannot say they are just as secure as a taper pin through an A2 FSB, but many have to be destroyed to get off. With a dimple properly made in the bottom of the barrel, the gas block is not going anywhere. To remove, we have to drill through the set screws, mallet or cut the gas block off. The ones we remove are almost never used again.
I would not hesitate a properly installed gas block with set screws. They have been used by Navy Seals for 20 years in the Mk18 and Mk12 platforms.
I would not hesitate a properly installed gas block with set screws. They have been used by Navy Seals for 20 years in the Mk18 and Mk12 platforms.
I'm super familiar with the reliability of set screw gas blocks. It's just a principle (that clearly doesn't really matter).
Nice. That's on the top of the list right nowThe only FSB adjustable gas block I’m aware of is the JP, which is a clamp-on style:
A thing high power shooters used to do was get an unfinished fsb and drill/tap them to mate to flats machined on the barrel, could adjust windage by tightening/loosening screws. It was pretty trick, amd guys have been drilling/tapping fsb to make them adjustable gas for a while. So getting an unfinished one might run about 25 bucks last I saw, which was before the rona, so I don't have a conclusive current price.
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If you switch to a FSB, it should be pinned in place. What are you currently working with?
What do you mean? In terms of tools? Currently it's just a barrel, an upper, and a 12'' handguard. I gotta get a gas tube and a gas block
Another tidbit was "back in the day" This is prior to flat tops-wow, imagine that! Guys would mill off the carry handle and fix a rail on top to attach a scope or an iron of some sorts. I remember a guy Sam Dayton in Portsmouth, Va. used to do it for the local match guys.
If you decide to pin the FSB, I recommend having a reputable shop make the barrel cut. After that it’s a punch and brass hammer.
Both White Oak Precision and Compass Lake made windage-adjustable front sights for NM competition before they allowed optical sights. Just use them and Loctite the setscrews with red once you set windage
Looking for gas adjustable not windage. Sorry should have clarified
If the setscrews are on the bottom of the front sight base, where the taper pins should be, then they are for centering your rear sight by adjusting the front sight for windage.
A setscrew, maybe 2, would be on the upper portion of a front sight base for gas adjustment.
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