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jrcii
06-23-17, 08:55
Hello All,

I'm building out a new 223 rifle that is just for longer range target shooting. It's going to have a 20" barrel with a rifle length gas system. I would like to be able to shoot it both suppressed and unsupressed.
Will I need an adjustable gas block for this? My only suppressor experience is with my 300 BLK SBR and it just magically works with both types of ammo.

Thanks,

JRC
thopkins22
06-23-17, 09:21
No, a properly sized gas port will work just fine suppressed and unsuppressed from carbine length systems all the way to rifle length systems.

If you want it to run "optimally" suppressed, then an adjustable gas block can accomplish that, but if it's the correct size with quality ammo it will be reliable without any kind of doohickeys. It will cycle slightly harsher, but that's going to be mitigated a great deal by the rifle length system.
daniel87
06-23-17, 09:33
A rifle or a5 buffer setup would be ideal. It should help compared to a carbine buffer

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jrcii
06-23-17, 09:37
Yes. I'm going to use a Gen2 Magpul PRS stock so it's going to have a rifle buffer.

The thing is that I have a Geissele gas block left over from buying one of their rails and I'm trying to decide if I should use it.

Perhaps I should contact Ballistic Advantage and see what their gas port size is.

Thanks,

JRC

A rifle or a5 buffer setup would be ideal. It should help compared to a carbine buffer

Sent from my SM-G900P using Tapatalk
markm
06-23-17, 14:34
You shouldn't need an adjustable. Longer systems are more forgiving in my experience.
tom12.7
06-23-17, 17:45
What size is the gas port?
It is possible that you may not have to do much to do, but it is also possible that you may have a lot to do.
Potss
06-25-17, 10:00
Need? No. Want? Yes. Less recoil, gas in face, parts wear, and noise.
voiceofreason
10-06-17, 20:27
try it before buying anything, depending on the ammo as well
hdrolling
10-06-17, 21:24
Do you want to be the guy at the range with a weapon that isn't working because you thought you might not need it going from un-suppressed to suppressed?

Do you care about downtime after you realize you needed one and now have to order and remove the old and reinstall the adjustable?

For my last build, I decided while it was apart I was going to use the adjustable just in case. I bland to load my own rounds someday as well so I can adjust for that as well.
MisterHelix
10-12-17, 08:38
Adjustable gas blocks can tune a suppressed/unsuppressed rifle or carbine nicely. I use an SLR Sentry on my hunting AR in 6.8spcii, and it performs well.

It does introduce an additional point of maintenance, and possibly an additional point of failure. If set to "suppressed", the rifle may not lock back when unsuppressed. It requires that a 2mm hex key be available. If not cleaned/lubed it can bind.

With that in mind, my "fighting rifle" (12.5" Noveske 5.56x45) does ~not~ have an AGB, even though it would cycle smoother when suppressed with one.
markm
10-12-17, 11:00
Need? No. Want? Yes. Less recoil, gas in face, parts wear, and noise.

We've choked down gas ports and still had gassy stink guns. Also, my adjustable gas blocked sbr with suppressor... although tuned to wonderful cycle/function, had so much ejection port "snap" that I couldn't shoot it without ear pro. I ended up dismantling the gun. I don't know why that particular set up was so snappy, but the gas block didn't reduce noise for sure.
tehpwnag3
10-13-17, 11:22
This has been my experience with nearly all AGBs. If set properly, it's actually not a bad thing unless you prefer to tune for each load and/or w/wo can.


If not cleaned/lubed it can bind.
tom12.7
10-15-17, 17:21
When you restrict the gas flow to the action by a gas block instead of a smaller base port, you will end up with more of the tear drop gas port erosion in the barrel over time. The width of the port opening in the bore for the sealing surface of the projectile determines the exposure to erosion. Inside the barrel, it is never better to have a port any bigger than what is required to regulate the gas flow. An AGB is just a band aid for a problem, not a solution.
joeg26er
10-15-17, 17:29
What about an adjustable Gas Carrier?
tom12.7
10-15-17, 17:37
It doesn't matter how far down stream the restriction is for the barrel port erosion when it is not done at the base port.
tehpwnag3
10-16-17, 14:16
You mean like a Gemtech carrier? I believe there was a review thread on here that had favorable results. Big bucks though.


What about an adjustable Gas Carrier?