Radical Firearms Low Profile Adjustable Gas Block - .750" - Set Screw Style
NOTE: Gas tube roll pin and Allen key not included.
Ratings & Reviews
Good block if you have the right tools.
by Shayne -
Bought two of these when they were on sale, they both had to have the adjust screw and set screw holes chased out with a tap to remove small burrs/coating buildup otherwise they wouldn't turn without stripping. After that they worked and installed great. Not that big of deal if you have the right tools, but can ruin your day if you don't. Got them adjusted and they both worked great (one is on a 300 BLK pistol, they other is on a 6.5 grendel rifle) For what I paid for them, I'm happy.
Won't fit barrel
by NATHAN -
Have purchased before and was a little snug on install, this one won't go on barrel at all at the step for the gas block, tried a spare I had and slid on fine. Looks like worn tooling is causing issues
Adjustment screw issue.
by Mel2 C -
Hobby enthusiast level installer. My barrel came with one dimple. I did not dimple the second set screw. After reading the reviews, I've seemed to have discovered an issue. I hope to update this review later if possible. Some have complained of the BCG still not locking back after full close on the gas port. It was happening to me. I inspected the Gas Block and found that the adjustment screw was having trouble traveling to the full rear position. Might be some burr or tapping issue. I had to apply some lube and additional force for the adjustment screw to bottom out fully. I have to hit the range again to see if I can successfully tune now, but I think I've discovered what was the issue for me. I didn't also use any Rockset around the gas port, and noticing some blow-by. I didn't need any on my clamp style Gas Block on another rifle, but I can live with this issue.
Works great on all three installs.
Installed on a 6.8 SPC build...works great, easy to install and adjust. My Allen wrench set fit perfectly. It does take two different sizes, one for the gas screw and a smaller one for the set screw. Perfect fit on my .750 barrel.
Dont waste your time or money!!!!
by Dan -
I typed a detailed review but it was too many characters. So I'll summarize, set screw not drilled straight, gas tube hole not drilled straight, and edge of gas block slightly mushroomed and would not slide over barrel without filing. Complete waste of money. Don't say you weren't warned
300 blk tamed.
by RONALD -
Installed on my 11.5" 300 blk and it works great. Couldnt ask for better.
Harbor freight sells the tool you need.
You can find the proper tool at Harbor Freight. I bought their ball tip hex wrinches. The snallest one is 0.05.
Great price, works as intended.
by Charles -
I read all the negative reviews and bought it anyhow since it was on sale. I have had zero problems with it. The gas adjustment screw will block flow down to almost zero. Some gas still flows across the threads but it's negligible and does not move the bolt. Mine did not require de-burring before installation, but I did lightly polish the inside to improve the fit. My only complaint: The 4-40 set screw uses a TINY allen wrench (0.05"??) which does not come with and is not easy to find.
by Jason -
Friend bought this for a new upper build. Had to de-but to get on the barrel. Couldn’t get a wrench to fit in the set screw. With some work was able to modify a wrench to fit and the screw was to tigh to come out.. tossed it and purchased one local that was good quality..
Functioning gas block...adjustable part questionable
by Matt -
I installed one of these on an over-gassed AR-10 in an attempt to tame it. I've got a few other adjustable GB and have had luck with them but decided to try this out. Following the instructions (adjusting the right screw), I was unable to get any change at all. Bolt continued to lock back even though the gas should have been shut off. It works as a gas block, just not adjustable (at least on the rifle I put it on)
WHAT WAS THAT GIANT BANG?
I, fortunately, didn't purchase this POS!!! It was a gift from a coworker. Well, at least now I know what my coworker thinks of me........Thanks ;) The gas block leaked immediately from the start, and the adjustment screw was completely useless. Regardless what direction you turn it, it had absolutely no effect on the pressure. Completely closed, was basically the same, as completely open?!? What a disappointment, but honestly, I wasn't expecting much. This obviously is not PA's problem, but they were absolutely concerned about the issue! The much larger problem is with the QC at Radical Firearms. To let a product, that adjusts gas pressure, make it to the shelves when it simply doesn't work and is obviously useless, is absolutely dangerous, and obviously, very disconcerting.
Will be the part that causes you to die!
by Thomas -
Valve screw and set screw backwards. Set screw does not lock in valve screw in any way shape or form. If you manage to get one that will actually adjust good luck getting it to hold in place. Ended up opening all the way managed to get about 100 rounds through it and the block completely cracked in half. Primary Arms has gone above and beyond resolving issue sent new gas block A+++ On PA's part but this product if I could select less than 1 star I would. Spend the extra 20.00 and get a better adjustable block!
Make sure you're tuning with the correct screw.
by David -
Make sure you're adjusting the correct screw. The front screw is the one that controls the flow. The side screw is the set screw once you have it dialed in. Mine measures .755 which allows some gas to escape just where I happen to be holding the rail. I may call PA and see if they can exchange as this one looks out of spec
DO NOT BUY AT ALL. OVER GAS ON ANYTHING YOU PUT IT ON!
by RaTiCuS -
Have to agree with the 1 star on this. Claims adjustable but it does not matter what you do with that set screw adjustment you get full gas output completely open or closed. Waste of time and money. Paid extra for the adjustable because of price but I am getting more cycling issues with this block completely closed off than I do with a standard gas block (smaller opening). This item really needs to be tested or pulled from inventory. I am sending this POS back
Worked fine for me
by jake -
Its inexpensive and it tamed my x39 AR. Would buy again.
absolute waste of money
Absolute POS! Even when closed all the way down it is still over gassed. Rifle is ejecting at the 1 o'clock causing stove piping issues. Purchased two of these at the same time and both of them are over gassed even when the adjustment screw is closed as tight as you can get it. Avoid at all costs
Didnt work for me
It fit good. I went to the range yesterday and it wouldn't lock the bolt back. I Started it off 1 turn from closed to almost where the screw was about to fall out. Changed magazines, buffer spring and it still wouldn't lock. I ordered a non adjustable gas block.
by Kyle -
My only complaint with this gas block is it scratched the top and bottom of my barrel going on, even with some oil. There must be burrs on the holes for the set screws.