300 BLK Diet

[Uffdaphil]

My AAC 9” SBR felt in need of a diet so I ditched the Sopmod and tried four less bulky stocks. The SL-K looked to be The One until I remembered I had an old FiberLite that had never looked right on anything I built.

It looks okay on the AAC, but really works on the cheaper 8.3”. With the can it weighs less than the 9” upper without. As pictured the 8.3” is 6lbs 5.8 oz. A half pound less than with the upper upper and with the lighter rail and suppressor the balance is perfect.

P.S. Do you use shims on a direct thread suppressor? I am thinking it might help break free if left on a loong time.

.8182

[Jerry R]

P.S. Do you use shims on a direct thread suppressor?

As best I recall (please correct me if wrong) AAC recommended not using shims on a direct attach. The can should not require timing, and a shim may introduce the possibility of a baffle strike.

[Former11B]

Shims would work better than a crush washer (always a no go) but the trick for direct thread cans is Teflon tape. I prefer the dark gray kind that’s for oily environments because 1) it’s darker in color and 2) it’s thicker and holds up better. Two passes around the threads and the can is held on nice and snug and no carbon lockup occurs. When it’s time to remove the can, just unscrew like normal and a gun cleaning toothbrush or a 9mm/.45 cal bore brush scrapes the threads clean for a new application of Teflon tape

[Uffdaphil]

Thanks Jerry. When I removed the Omega 9K I was surprised to find 4 shims. I have no recollection why I used them.

Former, that makes a lot of sense. I didn’t know there was other than white teflon tape.

[BoilerUp]

Shims would work better than a crush washer (always a no go) but the trick for direct thread cans is Teflon tape. I prefer the dark gray kind that’s for oily environments because 1) it’s darker in color and 2) it’s thicker and holds up better. Two passes around the threads and the can is held on nice and snug and no carbon lockup occurs. When it’s time to remove the can, just unscrew like normal and a gun cleaning toothbrush or a 9mm/.45 cal bore brush scrapes the threads clean for a new application of Teflon tape

Hmm, I wonder if that would be helpful even with thread taper lock / mounts.

[SINNER]

Use a few wraps of teflon tape on direct thread cans. Keeps them from loosening and allows easy removal. I use nothing but direct thread mounts now. Had enough of the QD bullshit.

[Uffdaphil]

Since I swap four taper mount cans around frequently, I’ll stick with anti-seize for those. The white Griffen goop is preferred to Aeroshell as it cleans off fingers more easily.

I used to have difficulty removing cans as I ignorantly thought you were supposed to unscrew while hot. Physics is not my strong suit.

[alamo5000]

Hmm, I wonder if that would be helpful even with thread taper lock / mounts.

No. It will prevent the can from seating all the way if you are putting it on that way and not just for the muzzle device.

Another option is Thread Sealant. It's a much better option vs the teflon tape.

[Joelski]

Since I swap four taper mount cans around frequently, I’ll stick with anti-seize for those. The white Griffen goop is preferred to Aeroshell as it cleans off fingers more easily.

I used to have difficulty removing cans as I ignorantly thought you were supposed to unscrew while hot. Physics is not my strong suit.I forget the commercial name of the stuff Griffin uses and sells (because who doesn't have the technical term "Horse Gipe" rattling around in their head?).[:D]

I'd like to source a container of it for my own use because that stuff works like a charm. Aeroshell comes in grease gun cartridges and is nowhere near the cost people charge for a thimble size container.

[alamo5000]

I forget the commercial name of the stuff Griffin uses and sells (because who doesn't have the technical term "Horse Gipe" rattling around in their head?).[:D]

I'd like to source a container of it for my own use because that stuff works like a charm. Aeroshell comes in grease gun cartridges and is nowhere near the cost people charge for a thimble size container.

The stuff they use is called "ST-3A Thread Sealant" which is (I think) a trade name for a specific product-- sort of like "Kleenex".

https://www.ndindustries.com/products/inert-sealing/st-3/

I think the one they specifically use and/or repackage is specifically for Aerospace stuff, which means it's got a much higher temp rating. If I am not mistaken it's temp rated to over 700 degrees F but can still withstand much higher temps for short periods of time.

It's basically VibraTite but with a substantially higher temp range ability. It also does not 'set up' like a red loctite or Rocksett.

[Uffdaphil]

Griffin’s anti-seize is Lok-Cease 20/20.

[BoilerUp]

Well, according to GA's website, you are both right as they sell both Loc-Cease 20/20 and ST-3A but for different applications. Anti-Seize vs thread lock. They recommend Loc-Cease for the taper mounts and ST-3A for threaded interfaces like end-caps or loose direct thread.

[alamo5000]

On a side note, I tried 'thread sealant' for a couple of my suppressors. Specifically on the Revolution 9--the end cap is the critical part that puts tension on the baffle stack so I wanted to make sure that it didn't work loose or anything.

The stuff works, but man, it was a PITA to get it apart once its set. Basically I had to use solvents to get it to come apart. Basically it was like it was really carbon locked on there, except it was the thread sealant. Getting that end cap off was a multiple day ordeal of soaking and so forth. That being said I didn't know what to use to undo it so I tried a few options.

Another 'issue' is the end cap doesn't have anything you can put a wrench on so I was a bit limited there.

This is the stuff I used:

https://www.permatex.com/products/thread-compounds/thread-sealants/permatex-high-temperature-thread-sealant-6-ml/

[Uffdaphil]

“Up to 400 degrees” sounds too low for a suppressor. Maybe that Permatex was baked hard.

[SINNER]

I've literally worked with thread sealants for 35 years. Over 450-500° the carrier in pastes hardens and becomes a hard set thread sealer. If I absolutely had to use a paste based product the only one I'd use is nickel based antiseize. But as I stated before, Teflon tape is the correct choice. That's real world experience on systems thst reach 1200+° daily. The internet may say otherwise. LOL

[alamo5000]

“Up to 400 degrees” sounds too low for a suppressor. Maybe that Permatex was baked hard.

To clarify, this is specifically and only talking about my cans that come apart. Those being a 9mm and rimfire only.

I don't know that I've ever fired a semi auto handgun enough for the end cap to reach 400 degrees F. Same thing for rimfire. With an MP5? Who knows what the temperature will be.

Of course I've baked the finish off of a 5.56 can before, but not so much with an actual semi auto hand gun.

I did notice that I could do a much better job on the application of the stuff should I try it again. By that I mean the last time I put it on the lower edge of the threads on the end cap itself. What it did was have almost a whole inch of the threads with sealant on them.

On the other hand if I just put some on the top few threads then seat it down the rest of the way it will serve it's purpose and will probably be a lot easier to get off.

Literally the only reason I'm doing anything at all is to prevent things from loosening under fire.

[Joelski]

On a side note, I tried 'thread sealant' for a couple of my suppressors. Specifically on the Revolution 9--the end cap is the critical part that puts tension on the baffle stack so I wanted to make sure that it didn't work loose or anything.

The stuff works, but man, it was a PITA to get it apart once its set. Basically I had to use solvents to get it to come apart. Basically it was like it was really carbon locked on there, except it was the thread sealant. Getting that end cap off was a multiple day ordeal of soaking and so forth. That being said I didn't know what to use to undo it so I tried a few options.

Another 'issue' is the end cap doesn't have anything you can put a wrench on so I was a bit limited there.

This is the stuff I used:

https://www.permatex.com/products/thread-compounds/thread-sealants/permatex-high-temperature-thread-sealant-6-ml/

Does the revolution not use a ratcheting wire to keep the cap from backing out? Seems a brilliant idea, but I don't take mine apart very often. I don't shoot rimfire ammo through my can so it doesn't get dirty enough in there for me to fk with! I bought spare wires and a .22 cal end cap when I bought my Alpha, but I haven't used any of them. It's good enough with 5.56, and I'm terrified I'd put the small cap on and forget to switch it back for my .300 BLK.

[alamo5000]

Does the revolution not use a ratcheting wire to keep the cap from backing out? Seems a brilliant idea, but I don't take mine apart very often. I don't shoot rimfire ammo through my can so it doesn't get dirty enough in there for me to fk with! I bought spare wires and a .22 cal end cap when I bought my Alpha, but I haven't used any of them. It's good enough with 5.56, and I'm terrified I'd put the small cap on and forget to switch it back for my .300 BLK.

Rev 9 just screws together with no ratchet system at all. IIRC Griffin made those ratchet end caps so those other cans could be used on a much wider array of hosts, ie full power rifles, but still have the take apart function.

I have dedicated caliber cans for everything except .45 which I shoot so little of it doesn't matter. 9mm is also the only thing that I have just one of. All others have at least two or more options (at least).

While I have in the past shot .22LR through my 9mm can I did it just as a test. It definitely works quite good. Like with anything else shooting 22 LR it will need a good cleaning in not that long should you ever want to try it.

That all being said swapping out a smaller diameter end cap, at least with 22LR it will make only a small amount of difference in sound suppression. You can notice it yes, but it will not be crazy more quiet or something. I have a 22 end cap as well and yes I did test it just because I'm curious.

[Former11B]

I’ve always used Teflon tape on direct threads, haven’t used any anti seize compound on taper mount threads.

I’ve only got one mount that locks up kinda snug and requires some effort to remove regardless of being fired or not. I think there’s a tiny tiny imperfection likely on the mount’s taper. Unfortunately it’s pinned in place so not an easy fix but the silver lining is that it’s not “bad”, just annoying sometimes. All my other mounts work just fine

[Uffdaphil]

I also have one problem child. It’s the Explorr blast shield. Even tightening with less than the normal force it’s bear to pop loose by hand. The same “stiction” on half a dozen taper mounts. No biggie, just make sure I have a wrench at the range.

I do like the porky Explorr over the original open end blast shield, but both are mainly just Gucci thread savers.



P.S. Yikes! I just noticed I put an Explorr 5.56 can on the BLK upper for the photo.

[alamo5000]

I also have one problem child. It’s the Explorr blast shield. Even tightening with less than the normal force it’s bear to pop loose by hand. The same “stiction” on half a dozen taper mounts. No biggie, just make sure I have a wrench at the range.

I do like the porky Explorr over the original open end blast shield, but both are mainly just Gucci thread savers.



P.S. Yikes! I just noticed I put an Explorr 5.56 can on the BLK upper for the photo.

Explorr blast shield?

One thing you can do to taper mounts is to treat them with frog lube or something like that. In fact do the thread end of the suppressor as well.

That being said I've never had a problem getting anything stuck on a taper mount.

[Uffdaphil]

Explorr blast shield from Griffin

8187

[BoilerUp]

I didn't know that existed. I've got the old school minimalist that I throw my 8.5" BLK when I remove the suppressor since the MD is slightly tucked inside the handguard, but this looks better.

[alamo5000]

I didn't know that existed. I've got the old school minimalist that I throw my 8.5" BLK when I remove the suppressor since the MD is slightly tucked inside the handguard, but this looks better.

I had an older version of the blast shield but I never used it so I gave it away. I don't even remember to who. That said, I learned the hard way how those can be valuable. Someone came over to shoot one day and they wanted to hear how loud my SBRs sounded unsuppressed so they could make a comparison. Naturally, not even thinking about it, I obliged. It was LOUD. Also it was really dry at that time so I was kicking up dust and some fine sand with the muzzle blast. That stuff got in my eyes even though I had eyepro on. The concussion was crazy. I couldn't even imagine shooting those things unsuppressed indoors.

[Joelski]

I feel like my 5.56 SBR is every bit the ear-splitting, head cracker my 18" 308 AR is. I tested it in a shoot house and came right back out and got my can for it. I like Griffin Flash-Comps and run them on every rifle I have, but the newer ones have more in common with a brake than a comp, IMO.

[Stone]

Breaking the sound barrier 2 feet away from your brain pan has a way of reminding you that you forgot to put your ear pro on... Ive rattled my teeth a few times and its painful on the ears and hangs with you for a while afterwards...

[Joelski]

And even with ear pro, a good blast in a confined space will rattle and twist your axons and dendrites. Hell, that kind of concussive force can take you anywhere on the CHI damage chart from a stinger up to DAI (very bad).

Directable concussion is one of the big DARPA technologies in warfighting. Look at Havana Syndrome; being able to amplify and place that kind of force inside your grape will liquify brain matter. Kinda takes all the fun out of shooting at assholes.