One of the most popular AR-15 upgrades in recent years has been the adjustable gas block. It’s so popular, some folks now insist that every AR-15 should have one. But is that true? Brownells Gun Techs™ Caleb and Steve say there are situations where an adjustable gas block is useful, but it’s NOT a cure for every gas system problem. Scenario: your AR is under-gassed – doesn’t have enough gas flow to cycle the action reliably. Will an adjustable gas block let you “dial up” more gas to fix it? Nope. When you fire a shot, a little gas exits the barrel through a port under the gas block. The gas block’s corresponding port is LARGER than the one in the barrel. An adjustable block can only RESTRICT gas flow; it can’t draw MORE gas from the barrel because that’s limited by the barrel’s gas port. This will not help an under-gassed AR-15! Manufacturers often over-gas their guns to ensure reliable cycling. You may actually need to reduce the gas flow, and an adjustable gas block is the way to go. You could also install a heavier buffer to counteract the excess gas, but Caleb explains why an adjustable gas block is the better solution. Steve likes to dial down the gas flow on AR-308s to make ’em shoot softer. So the myth is half-busted: You don’t always need an adjustable gas block, but it can be very useful on an over-gassed AR-15.
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How do i know what diameter gas block i need🤔
My theory on things buy want to cry once that goes for ammo to the barrel BCG and buffers test in conjunction you want quality oh regular M 16 BCG is fine but if you start going with lightweight cut out BCG‘s that just look cool because they’re super light and white not the reciprocating bass you’ll have issues you can get both bounce all sorts of different issues that’s why I stick with heavy M-16 BCG‘s I did recently just to order a nickel polished over a nitrated finish type bolt carrier to test it out 180 bucks so we’ll see if it runs good but I prefer you’re just standard plain Jane chrome lined carrier but it has a natural lubricity to it and what not so curious do a little testing with that but as far as gas systems if you have an over gassed say when Daniel defense Around seven years ago had over a guest MK 18 for the commercial market I suggested using a heavy buffer like an H2-3 but I run those in literally everything I have very very smooth specially the one I have the super 42 it has a triple braided wire system that gets all the crane cool out of your buffer system and makes it silent it also aids dramatically and recoil I have noticed and it lasts at least 5 to 10 times the life of a standard buffer system and they are only between 70 to 100 bucks depending on if you get an H one or an H3 and then they also sell them with buffer tubes and I usually do that if I’m doing a build because GEISSELE makes some amazing offer tubes especially if I’m using one of their rails their type three hardcoat anodized in different colors like ATC black gray and in different lighting scenarios it gets darker and lighter which I would like with analyzing process basically gives your rifle a self camouflaging affect in different lighting scenarios to wear a good look super tan and then you come indoors and different lighting and it’s dark and they’re castle nuts are just so clean I would just pay literally just for one of their castle not because It looks like they friggin use the best of the best and then yeah I’ll polish young and clean them and analyze them so there’s no little things and scratches and stuff like is he on most out of the box castle nuts
Now I need to purchase one. I have a db 10 that is hell on brass and kicks almost as bad as my 300 win mag with no brake.
Gonna be running an adjustable gas block once I get my suppressor, along with a heavy buffer tube/heavier bcg
If they wanted to upload a video just for the sake of content; here it is. Things to consider: Gas port hole size, gas block to port hole alignment, rifle gas length (carbine, mid, rifle), caliber, rifle type (hunting, sport, combat), suppressor setup, range engagement. I mean, if you're grabbing a rifle off the shelf, fine, who cares as long as it works. But, if you're considering a build of your own and want something that shoots better and more balanced than your $700 sports store make; highly consider incorporating an adjustable gas block. After all, your rifle is an engine, your finger is the ignition. Make your engine drive best for you.
Very informative, thanks guys!
Happy new year guys ! I have a question about the gas block adjustment on my AR 15 geisele super duty . Is it adjustable gas block on my AR ? By the way, this is my first time to upgrade or modify my rifle.🤔 thank you you guys are great
Are Adjustable Gas blocks (AGB) absolutely necessary when using 'lightweight' BCG's? I have (2) Faxon Lightweight Gunner BCG's but don't want to install the (AGB), unless it is over gassed. What buffer & spring should I use with these Faxon BCG's when no adjustable gas block is installed?
Would you use an Adjustable gas block on a 9" 300 Blackout you intend to suppressed?
Issues that come from over gassing ? Thanks
how about when using a suppressor, would an adjustable gas block help with all that back spray?
how do you determine what weight buffer to use if you are over gassed?
Oh and im suppressed also.
I have an ar15, adjustable gas block installed. I have the block completely closed and my bcg cycles and locks open with last round? Why? Shouldn't this scenario stay closed?
I’m gonna get my hair like his 50s looks sick
what would you recommend for a good cheap budget option adjustable gas block, preferably under $30.?
One thing adjustable gas blocks are good for are suppressor use. Attaching a suppressor will significantly increase gas pressure so being able to reduce that to maintain balance is a good thing.
Upgrading my 300blk AR Pistol to run with a can, should I go with Adam's Arms piston kit or Superlative Arms adjustable DI block? 🤔
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Short answer, YES!!! If you are building one. Just include it. Clamp on only Set screws are for losers. For your existing gun? Only if you are over gassed.
Well, the answer is NO. When the Army gave me my first M-16A1; there is or nothing to adjust if it shoots that is all they want.
Most barrels are over gassed from the manufacture. Some barrels need a combination of gas and buffer/spring mods to calm them down.
Especially short ones, they are violent.
Thank you gentlemen
If you think it's under gassed it's either not lined up properly or you need a lighter/smaller buffer
Very well explained good job guys
America can be energy independent again with a oil extraction lease from Cabeb’s
hair…
Dude needs more hair gel.
Where should my sister store her depleted uranium rds.?
It’s like watching the gun community’s versions of Sam Elliott and Jesse Eisenberg.
I don't need an adjustable gas block I just want one, what the heck why not
First determine what ammo they are using.
Great video. Will Brownells ever offer free shipping? Most companies do nowadays. Kinda sucks spending couple hundred dollars and then paying $15 shipping.
How do arctic and other extremely cold conditions affect a rifles gas system? Do these conditions typically require more or less gas?
Good vid guys! I was getting ejections from 1:00–1:30ish. Followed sprinco's article on gas/ejection diagnosis. Tried a heavier buffer, nope, tried a heavier spring, this started to mess up the timing and cycling of the firearm. Closest with spring/buffer combos I could get was around 2:30 with reliable functioning. Slapped on a adjustable gas block, rifle spring an h2 buffer (A5 length setup), tuned it in a few shots.
Not only does it shoot smoother and softer, it is cleaner as well! And my brass doesn't look like it has been through the ringer, sweet 4:00 ejection, all the brass lands in a nice pile.
Caleb could have been in the movie The Outsiders as a greaser
I will stick with my Gas Piston conversion of my Colt AR, I don't have gasses coming into my action unlike the Gas tube system and I don't need gas rings on my bolt. My AR runs cleaner and cooler. runs like an AK !!!
I built an AR-308/7.62×51, the barrel gas port too close to the muzzle not allowing enough gas to bleed off to the BCG. Problem solved by opening up gas port, but now too much gas; installed an adjustable gas block; problem solved. But now, I encountered another problem with some factory ammunition M80 primer flow in the bolt firing pin hole; another problem solved PJ Enterprises Enhanced High-Pressure BCG, it worked.
If you using a suppressor, you will want an adjustable gas block.
I had a DPMS AR-10 that was under gasses and the problem turned out to be a miss-aligned gas block. Once the proper alignment was achieved, the rifle functioned perfectly.
Love the honesty 🎶🤩
I was thinking about this and buffer for a 224 upper build.
Eh… I don't know about that conclusion. My experience has been one of plugged up adjustable gas blocks (one JP low profile and a Seekins) at the worst possible time. Both times I found it easy enough to correct (just clean it), but in both cases I had no warning until the moment it was just too crumb'd up to work right and I ended up ruining good runs because of "no alibi" rules. Since then I've removed the adjustable gas blocks and replaced them with straight Geissele low profile blocks (pinned, with the provided large roll pin) and I tweak the buffer/spring combinations until everything is shooting as soft as I can get it, with 100% reliability. Yes, I agree I'd rather keep the excess gas out of the gun from the get-go and I can't change ammo in the middle of a match but, I can't afford to bleed points because of what the sanctioning body considers an avoidable malfunction.
I avoid adjustable gas blocks like the plague. I’d just rather have the simplicity of a slightly over gassed system that just works without having to fine tune anything.
I was lead to believe that the adjustable gas blocks were primarily for supressor use to stop excessive gas blowback into the shooters face.
I started using AGB's about 6-8 years ago, great for over gassed but you don't cure under gas or alignment issues. What I like most is the fine tuning for minimal recoil, and using different loads.
appreciate you guys !
I would love to see an adjustable gas block instead of a adjustable piston for a AK, that won't break the bank lol. I'm sure it will happen in the future
HK 416 gas station better than AR gas tubes!
Some of my hard core buddies claim that adjustable gas blocks are more succeptible to failure but I dont see how.