My Suppressor is Teaching Me a Lesson

The other day, I got in some range time and put 150 rounds downrange with my 5.56 AR pistol that has an 11.5-inch barrel and an arm brace. More rounds and time than I would like were spent sighting in. The result was that I learned a couple of lessons. That’s OK; it’s better to learn them on the practice range than in the real world.

A Lost Zero

The first shots from the gun formed a nice tight cluster at 36 yards, with three or four of five shots touching and two in the same hole. The problem is the shots were a little low and to the right.

That’s frustrating, because I know I had sighted the gun in before. But no worries, I was planning to mount a suppressor on it, and that will change the point of aim in any case. I’ll sight in after I set it up.

Adjusting the Zero

I remove the flash hider and screw on my Banish 5.56 suppressor. Then I shoot the target again, and my first thought is, “Wow, that’s nice and quiet.”

I still get a nice tight group, but now the hits are even lower. I remove the cover for the adjustment screw and determine which way to turn it to make the bullet go up. It’s ½ an MOA per click, and I am three inches low at 36 yards. That’s about six clicks per inch at this range, so I turn the screw 18 clicks up.

I settle back in behind the gun and shoot five more rounds. I walk downrange to the target and find the hits are about six inches too high. What? Three inches high I would understand. That would mean I was wrong, and the adjustment was 1 MOA per click. I go to the manufacturer’s website and download a PDF of the manual. Nope. It’s ½ an MOA per click. I check my math. It’s not my math.

Ok, no problem. I’ll dial it back down 9 clicks, half my prior adjustment. That should put me right on center. I shoot five more shots and examine the target. This time, I can’t even see where the bullets hit. Then I notice there is a bullet hole in the wooden cross member below my target. Was that there before? I don’t recall. I go back, aim at the top of my target and fire five more rounds.

There was a nice tight group hit about nine inches below and three inches to the left of my point of aim. WTF? I didn’t even change the windage. At this point, I can only blame one thing: the optic.

Don’t Buy Cheap Optics

This was not a no-name Amazon Chinese optic, but it was a less expensive optic from Atibal, a lower-cost supplier. They are based in Arizona, but their optics are made in China. I think the problem is I purchased their $89 model instead of their $199 model. Admittedly, this optic is five years old. Hopefully, their quality has improved. A quick review of their website shows they have favorable reviews.

Atibal has a lifetime warranty, so I may send it in and see what happens. But that wouldn’t help me in an SHTF scenario. So the first lesson I learned is one I should have known: don’t buy cheap optics if you can afford better.

I dig into my big box of gun parts and accessories and find I have two optics I could mount on the gun: a used ACOG I took off another gun when I mounted an 1-8x LVPO and a new Holosun I picked up on sale. Thinking a 4x fixed optic wasn’t ideal for a gun with an 11.5-inch barrel, I opted for the Holosun, which is also made in China.

I mounted it and took 15 rounds to get it sighted in. Now I could do some real training.

Let the Fun Begin

This is the gun on which I mounted the Olight Sigurd Angled Foregrip with a built-in 1450 lumen light. While I wasn’t doing any low-light shooting, I liked the way the grip felt in my hand. I often mount stubby vertical foregrips on my ARs, but I liked the angled one. That’s good because you can’t use a vertical foregrip on a pistol if you want it to stay a pistol. (Just another ATF rule that makes little or no sense.)

I shot from both sides of a barricade, engaged four different targets at different ranges from different positions, and shot some steel plates. I also did reload drills and practiced headshots. Everything was going fine, and then the groups started opening up. This was especially obvious when doing headshots since I slowed down a bit with them.

Oh no! Was another optic going bad? Not this time. The suppressor had come loose, although not loose enough to result in any baffle strikes. My guess is it vibrated just enough to enlarge my group size.

I don’t know if it became loose because the titanium suppressor heated up faster and expanded more than the steel barrel or if the vibration of the gun going off caused it to loosen. Maybe both. This is clearly a downside of a screw-on suppressor. Sure, it will fit any of my ARs without costing me an extra dime, but it might work its way loose after 100 rounds.

Not a problem you want to deal with in an SHTF scenario.

When it had cooled down enough to touch, I tightened the suppressor, and the tighter groups returned.

Preventing the Problem

I did some online research, and this is a known problem with direct screw-on suppressors. I guess I should have expected that. The solutions varied, but using red Loctite was a frequent solution.

The next weekday, I called Silencer Central (they have excellent customer service) and they admitted it could happen. They recommended I use Rocksett, which is a thread locker designed for suppressors and muzzle brakes. I had never heard of it, but it is supposed to be easier to remove than the red Loctite. I expect a bottle will be on my next Amazon order.

That’s the second lesson, which I also (mostly) knew. Use Loctite or Rockset to ensure things stay tightened down on your firearm, not only when you build it, but when you mount something to it.

They also suggested using an adjustable gas block from Superlative Arms. I may do that, although it will mean removing the handguard and swapping out the original gas block. I am more than capable of doing this, but it’s not my idea of fun. Sounds like a winter project.

A Sweet Little Gun

Overall, I am very pleased with my pieced-together low-budget AR pistol, which I built back in the fall of 2022. Since that build, I added a new pistol brace, the grip flashlight, plus the new optic. The result is a lightweight, handy gun, even with the suppressor mounted.

I originally built this AR pistol thinking it would be a lightweight weapon for my wife. So far, she hasn’t used it, but it won’t go unused because I like it! I think it will make an excellent gun to carry on the Polaris Ranger. Once I get the Rocksett, it will become a semi-permanent home for this suppressor.

I was able to squeeze the Allen key that came with the light, it’s charging cord, a spare 2032 battery for the Holosun, and two tools that came with the optic into the compartment of the Magpul pistol grip. It doesn’t even rattle. Sweet!

The 36-yard Zero

There are countless arguments online about what distance you should sight in your gun for a good battlesight zero. I ran 25, 36 and 50 yards through the ballistic calculator and chose 36. I can hold my point of aim, and if I do everything right, the bullet should never be more than 2.9 inches higher than the point of aim or lower than .7 inches between the ranges of 25 and 225 yards. That’s perfect for our forested mountain, where seeing more than 100 yards can only be done on a road or someone’s cleared property.

This is definitely a short-range gun, and I would not feel under-armed if I grabbed it in a homestead defense scenario. It’s making me a believer in the benefits of shorter barrels.