Posted on 06/23/2015 10:05:16 AM PDT by w1n1
Did you know that replacing the factory gas block on your AR-15 with an adjustable gas block can improve your rifle’s performance?
Let's backup, What is a Gas Block?
The typical factory gas block is pinned onto the barrel in front of the polymer handguard as part of the front sight assembly. If your rifle features a free-float aluminum handguard, then the gas block is typically a low-profile type that fits under that handguard. The job of the gas block is to take some of the hot gas from behind the bullet that comes through a gas port in the barrel, and direct it into the gas tube which drives the bolt carrier and cycles the action. Most gas blocks on factory AR-15s are fixed, meaning they just provide a path for the gas from the barrel to the gas tube.
With a fixed gas block, all the gas and pressure that comes out of the gas port in the barrel will be used to cycle the action. In most AR-type rifles there is intentionally more gas than needed, so that if the gun gets dirty, it will continue to cycle. But often this overgassed situation is more than is really needed, adding to the recoil and increasing wear on parts. That’s where adjustable gas blocks come in. They provide a way to cut off a portion of the gas flow so the action can be driven less forcefully.
The Benefits
So whether you fall into one of these two groups Joe Tactical or a 3 Gun competitor, here are some pros of having a gas block in your AR installed:
1) You can tune your rifle to run just as hard as is really needed, and by doing so you will experience less recoil and less movement of your sights off target, so your follow-up shots can be faster. What’s happening is that your bolt carrier group will cycle hard enough to extract, eject and feed reliably, but it won’t slam to a stop as hard at the rear of its stroke.
2) There will be less stress on your operating parts because they are not running any harder than necessary. It’s like running your car engine at lower revolutions per minute. Don’t worry, it will not feel slower while shooting.
3) Since you will be cutting off some of the gas going into the bolt carrier group, it’s common to get less carbon build-up in your bolt carrier and on your bolt. This will cause your gun to run cleaner, which can result in better reliability and easier cleaning.
Read the rest of the story here.
Tune the rifle by adjusting the gas hole, not some mickeymouse add on.
Interesting. Thanks.
The “gas hole” is not adjustable, hence the adjustable gas block. Which isn’t really a micky mouse add on as every AR has a gas block.
just a bit of humor about mini-14s. Apologies in advance. :)
The barrel is dirt simple to change, and barrels can be ordered with any size hole desired, or no hole at all.
Adding another failure point to any weapon is never a good idea.
And any gunsmith worth a screw driver knows how to adjust any gas hole, up or down.
I've never heard of an adjustable gas block failing and if it's good enough for competitors who tax their ARs to the limit then it's good enough for anyone. Further it's not like they were invented last week, they have been around for decades.
Or as we call it the “Wheel of Misfortune”.
Thanks for the post. As a new AR owner, I’m trying to bone up on everything about my rifle. For now, I just need to get to the range and shoot the crap out of it.
I’m hoping it solves the problem of excessive back pressure associated with suppressors. The ability to reduce felt recoil in a .308 AR10 will be nice too.
A lighter bullet helps felt recoil, the 125 gr SST from hornaday is noticeably more comfortable to shoot than the 147 gr mil loads.
Gas guns and suppressors are not made for each other, if you cut the gas to the point you notice a difference, you will cut the reliability of the weapon. If it is just a paper puncher, dial the gas back to zero and open it up a little at a tile till it works again. The best solution is a bolt gun.
If you reload, you can custom load ammo that is not as gassey by using different powders. With commercial ammo, you are pretty much stuck.
The suppressor increases the gas pressure and volume, there is not a blowback effect in the bolt cycle.
Your suppressor effectively lengthens the barrel and causes more gas dell time on your pressure chamber in your bolt carrier.
Have you looked into the suppressor bolts now available? They have a suppressor/no suppressor adjustment and reportedly work well.
Most semi-auto guns run well on one type of ammo. They can be set up for whatever you want, but trying to get one to run on everything is a lesson in frustration. Set the gun up for suppressor only use is optimum .
The Gen II recon uses a proprietary bolt and carrier. I don’t know that I want to replace it or if I even could given that there’s no such thing as a mil spec AR10. If we were talking about a mil spec AR-15, I would consider that option. I’ll see if the AGB solves my problem which I am pretty confident is overgassing secondary to the suppressor. I like the idea of being able to just switch back and forth between settings for suppressed and unsuppressed. If it doesn’t work I’ll start messing with buffers. I think it just needs retuned for the suppressor.
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