SLR gas block reliability?

I've heard some people say not to use a AGB for a SHTF/HD/SD gun, but I can't stand shooting mine suppressed without the gas turned down. Major gas to the face and hard to control with hot 5.56 NATO. I've used the SLR blocks on all of my rifles since I got a suppressor. Still, I can't help but feel like it's a failure point waiting to happen compared to a fixed block. But maybe I'm overthinking things. I can't seem to find any negative feedback about SLR gas blocks failing. And even if it's my primary HD/SD rifle, it's likely I'll only ever need to defend myself with a few shots, not wage a war with an army.

What think ye?

OLM-Medic said:

I've heard some people say not to use a AGB for a SHTF/HD/SD gun, but I can't stand shooting mine suppressed without the gas turned down. Major gas to the face and hard to control with hot 5.56 NATO. I've used the SLR blocks on all of my rifles since I got a suppressor. Still, I can't help but feel like it's a failure point waiting to happen compared to a fixed block. But maybe I'm overthinking things. I can't seem to find any negative feedback about SLR gas blocks failing. And even if it's my primary HD/SD rifle, it's likely I'll only ever need to defend myself with a few shots, not wage a war with an army.

What think ye?

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I have one on my primary HD gun.

I've been using them on my two suppressed rifles - 16" 223 and 10.5" 300BLK - with zero failures. Just make sure to close it off when you clean the barrel so the screw doesn't get gunked up. I had that happen one time. Everything still worked but it was hard to adjust until I took it apart and cleaned it.

Stories of screws failing on adjustables are out there. I did have an adjustable gas block fail, but it was not an SLR. I have SLRs on all my rifles now, they have never failed.

Conversely, without an adjustable things like the firing pin may be more prone to break with a supressor (that also happened to me shooting suppressed on a rifle without an adjustable gas block).

Seems to me its a trade-off. Shooting suppressed, something will wear faster. if the adjustable fails, you have a bolt action rifle. if the firing pin fails, you have a club.

mdbassplayer said:

I've been using them on my two suppressed rifles - 16" 223 and 10.5" 300BLK - with zero failures. Just make sure to close it off when you clean the barrel so the screw doesn't get gunked up. I had that happen one time. Everything still worked but it was hard to adjust until I took it apart and cleaned it.

Click to expand...

I do close it off when cleaning, but I don't always work it in and out after a few hundred rounds like they say you should to prevent it from getting stuck. I probably won't care too much if it gets stuck. I'm more worried about some catastrophic failure turning it into a single shot, or worse.

So far it's worked well. Next range visit I'm actually going to turn the gas down even further than I have it now. With low power .223 it's a dream to shoot, but I busted out some 5.56 NATO the other day and it was very over gassed, shells flying far in front of gun. Noticeably harder to control the recoil for quick shooting which affected my performance under the shot timer negatively compared to what I'm used to.

I have it tuned to shoot my weakest load (Wolf) UNsuppressed, plus two clicks extra for reliability. Next time, I probably will just have it tuned to shoot my weakest load reliably suppressed only, and make sure 5.56 NATO functions reliably UNsuppressed as well, just in case. I rarely shoot unsuppressed anymore anyway, and if SHTF I'm not using my stash of Wolf anytime soon. I'd rather have the extra recoil control with my 5.56 nato HD ammo.

danb said:

Stories of screws failing on adjustables are out there. I did have an adjustable gas block fail, but it was not an SLR. I have SLRs on all my rifles now, they have never failed.

Conversely, without an adjustable things like the firing pin may be more prone to break with a supressor (that also happened to me shooting suppressed on a rifle without an adjustable gas block).

Seems to me its a trade-off. Shooting suppressed, something will wear faster. if the adjustable fails, you have a bolt action rifle. if the firing pin fails, you have a club.

Click to expand...

Great point. That brings me to my ultimate question, what exactly happens if the AGB fails? Will it turn into a bolt action? Or will it be in a undergassed state, which may just cause consistent malfunctions? I would rather have it be a bolt action than a double feed machine. I'm really not sure what would happen though.

OLM-Medic said:

Great point. That brings me to my ultimate question, what exactly happens if the AGB fails? Will it turn into a bolt action? Or will it be in a undergassed state, which may just cause consistent malfunctions? I would rather have it be a bolt action than a double feed machine. I'm really not sure what would happen though.

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Best way to find out is to experiment by inducing the failures you anticipate. Remove the gas screw, fire a few shots, and see what feeding problems happen.

If you shoot the sh!t out of the gun and it works, chances are it'll continue to work. I wouldn't worry about it too much on a gun you've proven to be reliable.

ideally you would have a gas port sized just right, with a short enough dwell, and a heavy enough buffer that it would be tolerable suppressed, and reliable with or without a can. There are failure points in adjustable blocks that just aren't there in non-adjustable, they can clog, the screws or detents can break or back out, and depending on the model, a couple other issues. A good block with click/detents like the SLR can limit failures, I really like the new Aero blocks and Superlative arms, the screws and detent designs are more rugged, and they can be freed up if they seize, and tend to cut gas close to the hole and have a larger volume above the screw into the tube so debris can be cleared out with a failure drill. I've shot enough that I've seen good adjustable blocks cause failures, but have seen a lot of good parts causse failures, and even then the number is nothinng compared to ammo problems or user error, so in all likeliehood they should be fine.

I would be more concerned about staking the gas block so it does not move than an adjustable gas block screw falling out.

danb said:

Seems to me its a trade-off. Shooting suppressed, something will wear faster. if the adjustable fails, you have a bolt action rifle. if the firing pin fails, you have a club.

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I would agree - if reliability and durability are paramount, then skip the adjustable gas block and and make sure the buffer and springs are right for the ammo/suppressor and stake the gas block so it does not move and get out of alignment.