Page 1 of 2 12 LastLast
Results 1 to 20 of 27

Thread: Suppressor with 6.5 Grendel

  1. #1
    Unwashed
    Join Date
    Aug 2017
    Location
    Austin, TX
    Posts
    16

    Suppressor with 6.5 Grendel

    I have heard it's not the easiest to get the LaRue brake off the rifle initially. My new Grendel has not arrived yet and I was wondering if I should ask them to ship it without the brake installed. I have a Thunder Beast suppressor, but I wasn't sure if it was going to be way over gassed with the Thunder Beast. Have any of you guys shot something other than the TranQuilo suppressor on your LaRue Grendel? Thanks for the help.

  2. #2
    Bloodstained
    Join Date
    Aug 2017
    Location
    Nomadic
    Posts
    57
    I assembled mine myself...so, cannot comment on whether it was hard to get off. I would suspect the issue of over gassing will be roughly the same as any other rifle not setup for suppressor use in 6.5. LaRue, based on the claims for the Tranquilo, doesn't really have any reason to design their rifle around a tweaked, suppressor specific gas system, especially since they make a adjustable gas block for the 7.62 guns.

    Curious to hear the group's findings on this to compliment my pure conjecture. ;-)

  3. #3
    Super Moderator LRRPF52's Avatar
    Join Date
    Sep 2014
    Location
    Utah
    Posts
    4,751
    LaRue built the Tranquillo to reduce back pressure, did a lot of testing with it and built back-pressure test instrumentation to demonstrate it.

    Everyone that has shot one says the rifle cycles the same as it does without the suppressor on, including their 18" MLGS Grendels and .260 Rem PredatOBRs.

    I'm very tempted to order one.

    I just started the paperwork on my TBAC Ultra 5 30CB yesterday, got to hold it at least. I'm allowed conjugal visits they said if I bring in my blaster with the brake ready to go. I've shot them a bunch on Grendel before, and already know how they sound. The Ultra 5 is 7.6 ounces and rated to .300 RUM on a 22" barrel even. It will handle 18" 7mm RM and .300 WM. 11.5" 5.56 and 6.5 Grendel.
    NRA Basic, Pistol, Rifle, Shotgun, RSO

    CCW, CQM, DM, Long Range Rifle Instructor

    6.5 Grendel Reloading Handbooks can be found here:

    www.AR15buildbox.com

  4. #4
    Bloodstained
    Join Date
    Aug 2017
    Location
    Nomadic
    Posts
    57
    7.5 ounces and it handles .300 RUM? Wow...that's a hell of a thing.

    Personally, I think I'll go the Tranquilo route when I eventually get around to it...maybe after I learn to shoot.

  5. #5
    Unwashed
    Join Date
    Aug 2017
    Location
    Austin, TX
    Posts
    16
    I have a 30P-1 that has been re-baffled to the new design and an Ultra 7 6.5 on the way. I would prefer to shoot the new LaRue with one of these on. I just wasn't sure if it would jack with the rifles performance.

  6. #6
    Super Moderator LRRPF52's Avatar
    Join Date
    Sep 2014
    Location
    Utah
    Posts
    4,751
    The 7" 6.5 Ultra will create a lot of back pressure and should really be used on bolt guns.

    I went with the Ultra 5 30CB because there is more opportunity for the gas to bypass in the larger holes in the baffles, with a shorter baffle stack, and I have seen them run on Grendels already.

    The main Grendel I plan to suppress will be 12". I'm going to use an adjustable gas bolt carrier on it.
    NRA Basic, Pistol, Rifle, Shotgun, RSO

    CCW, CQM, DM, Long Range Rifle Instructor

    6.5 Grendel Reloading Handbooks can be found here:

    www.AR15buildbox.com

  7. #7
    Quote Originally Posted by LRRPF52 View Post
    The 7" 6.5 Ultra will create a lot of back pressure and should really be used on bolt guns.
    I was not aware of this when I ordered my Ultra 7.

    While I have a bolt gun on order with Precision Firearms, I was hoping to use it on my AR. It's a PFA 16" carbine with a Adams Arms gas piston. Do you think this will work?

  8. #8
    Warrior
    Join Date
    Sep 2014
    Location
    S.E. KC, MO
    Posts
    269
    Quote Originally Posted by Capt. Morgan View Post
    I was not aware of this when I ordered my Ultra 7.

    While I have a bolt gun on order with Precision Firearms, I was hoping to use it on my AR. It's a PFA 16" carbine with a Adams Arms gas piston. Do you think this will work?
    It'll work... Just expect gas in the face due to the increased blow back

  9. #9
    Warrior Kswhitetails's Avatar
    Join Date
    Oct 2016
    Location
    South Central KS
    Posts
    270
    Adams arms has a selector for the gas port size internal to the block. Run the restricted size first, see how it runs. I'd be willing to bet it'll run, but be a little snappy. You'll like the piston especially suppressed - says the "hype".

    I've got a S&W M&P15 PSX, which is Adams' design, if not their actual kit. I love the piston system. Unfortunately, I don't yet have any experience firing it suppressed as my can is still a year from parole...

  10. #10
    Bloodstained
    Join Date
    Sep 2016
    Posts
    40
    Honestly, you can tune the rifle for the suppressor. Without an adjustable gas block (no experience with piston guns) the shooter's ear will be roughly the same suppressed or un suppressed. If you properly adjust things, you can get an AR into the mid 130s shooter's ear, and I would expect lower numbers with buffer and spring tuning, along with the lower pressure of the grendel compared to 5.56. I've yet to see the gas face with a gas gun that has been tuned for a suppressor.

  11. #11
    Chieftain Klem's Avatar
    Join Date
    Aug 2013
    Location
    Twin Peaks WA
    Posts
    1,126
    Quote Originally Posted by Kswhitetails View Post
    Adams arms has a selector for the gas port size internal to the block. Run the restricted size first, see how it runs. I'd be willing to bet it'll run, but be a little snappy. You'll like the piston especially suppressed - says the "hype".

    I've got a S&W M&P15 PSX, which is Adams' design, if not their actual kit. I love the piston system. Unfortunately, I don't yet have any experience firing it suppressed as my can is still a year from parole...
    I see Adams has a newer adjustable low profile version of their block called the 'P' series. Unlike their original three-position XLP it now has five settings - 100%/74%/53%/32%/11%. The old XLP piston has the three settings (Full, Half and Off) that I think you are referring to. I can vouch the XLP is utterly reliable in a 5.56 carbine but without a suppressor the normal setting is 'Half' anyway. That means you never use 'Full', and on 'Half' there's no further setting to restrict the gas when a suppressor is fitted... except fully 'Off' (single shots only). And it spits in your face with a suppressor fitted, but to be fair I don't think any amount of restricting the gas at the block is going to completely eliminate that.

    No doubt the newer 5-position 'P' series gives you more control, especially with a suppressor but I notice it all costs way more than it used to. Just the replacement block alone is $200 and it's still the old set-screw design (not clamping). The whole kit is $360. On the plus side the 'P' series is lighter and fits under handguards. Just be mindful that while receivers of a piston upper run cleaner than DI, once you fit a suppressor they become just as dirty. All the crud comes back via the chamber as it unlocks. You might be left wondering why you spent all that money on swapping out a perfectly reliable DI system for this.

  12. #12
    Warrior Kswhitetails's Avatar
    Join Date
    Oct 2016
    Location
    South Central KS
    Posts
    270
    That's disappointing, Klem. You're absolutely right, the piston system becoming DI-like dirty makes me wonder why piston a gun indeed. HOWEVER - the one saving grace for my piston hold-out hopes, is Larue's Tranquillo system reduction of back pressures and chamber gas levels. "LGE"?

    I can't wait to take the 556 barrel cartridge, put my mid length AA kit on it, and mount the Tranquillo. Maybe a year from now I'll be ready to tackle that test with gusto... A correctly suppressed piston system AR with little or actually NO face-gas sounds delightfully enjoyable. Especially when training my offhand abilities.

    If I may, I am Absolutely impressed with the AA piston carrier. This thing makes standard AR carriers look like Chinese vs Snap-on. The machining and finish are both incredible, and the nitriding is top notch. I almost thought it was blued at first. A little extra oil never hurt a carrier anyway.

  13. #13
    Chieftain Klem's Avatar
    Join Date
    Aug 2013
    Location
    Twin Peaks WA
    Posts
    1,126
    Quote Originally Posted by Kswhitetails View Post
    That's disappointing, Klem. You're absolutely right, the piston system becoming DI-like dirty makes me wonder why piston a gun indeed. HOWEVER - the one saving grace for my piston hold-out hopes, is Larue's Tranquillo system reduction of back pressures and chamber gas levels. "LGE"?

    I can't wait to take the 556 barrel cartridge, put my mid length AA kit on it, and mount the Tranquillo. Maybe a year from now I'll be ready to tackle that test with gusto... A correctly suppressed piston system AR with little or actually NO face-gas sounds delightfully enjoyable. Especially when training my offhand abilities.

    If I may, I am Absolutely impressed with the AA piston carrier. This thing makes standard AR carriers look like Chinese vs Snap-on. The machining and finish are both incredible, and the nitriding is top notch. I almost thought it was blued at first. A little extra oil never hurt a carrier anyway.
    Absolutely you may...and I agree, the AA piston is utterly reliable, never skipped a beat; both suppressed and unsupressed. The cases eject further forward when supressed and the receiver and spent cases get filthy, but it all works as it should.

    I'm thinking the only reason to spend $360 on an 'P' series piston is to keep the receiver cooler during high volume fire. That said, the fad that is piston uppers has been and gone as people realise that DI is also reliable, and always was.

  14. #14
    Quote Originally Posted by Klem View Post
    Just be mindful that while receivers of a piston upper run cleaner than DI, once you fit a suppressor they become just as dirty. All the crud comes back via the chamber as it unlocks. You might be left wondering why you spent all that money on swapping out a perfectly reliable DI system for this.
    That would be a serious design flaw - gas and crud venting back into the receiver.

    Just like a DI system.

    All kidding aside, the suppressor is a toy of convenience. If function is not satisfactory on my AR (which remains to be seen) it will be just fine of the bolt action rifle.

    And if it turns out the suppressor experience is something I just can't live without - then I get one that will run clean with the gas piston AR. Few problems a little money can't solve.

  15. #15
    Unwashed
    Join Date
    Aug 2017
    Location
    Austin, TX
    Posts
    16
    My rifle came in yesterday and I am really excited to give it a try. They shipped it without the brake attached, so I called LaRue and the tech didn't think my suppressor would be an issue. He said if it didn't run, I might have have to swap the spring in the buffer tube. I will give it a go this weekend and see what happens.

  16. #16
    Yesterday my FFL called - the tax stamp is in. Submitted last January, almost 9 months on the nose.

    Hope to get out to the range Monday with the AR.

    Still waiting on my bolt action Grendel from Precision Firearms.

  17. #17
    IMG_8081 (1).jpgSo ... how did it work out?

    OMG Klem was right. It wasn't so much that I felt gas blowing back in the face. But when the RSO called ceasefire for target change and I dropped my mag the top round on the mag was filthy. Attached is a photo of two Hornady 123 gr. A-Max from the same box of ammo.

    Guess I have a DI gun now. Quite a shock since my previous two semi-autos were a FAL and a 30 Carbine (both piston guns). It must have taken me an hour to get everything clean again!

    How do you guys put up with it?

    Anyway, I think I am going to put the flash hider back on the AR and restrict the can to the bolt action rifle.
    Last edited by Capt. Morgan; 10-23-2017 at 04:50 PM. Reason: Attach Photo

  18. #18
    Oh - and the brass ejects about 2x the distance. Almost as far as my FAL could chuck it.

  19. #19
    Warrior
    Join Date
    Sep 2014
    Location
    S.E. KC, MO
    Posts
    269
    How do I put up with it? I just look through the scope at the target and smile at the results.... LOL

  20. #20
    Unwashed burnsy13's Avatar
    Join Date
    Sep 2017
    Location
    'Braski
    Posts
    6
    Quote Originally Posted by Capt. Morgan View Post
    IMG_8081 (1).jpgSo ... how did it work out?

    OMG Klem was right. It wasn't so much that I felt gas blowing back in the face. But when the RSO called ceasefire for target change and I dropped my mag the top round on the mag was filthy. Attached is a photo of two Hornady 123 gr. A-Max from the same box of ammo.

    Guess I have a DI gun now. Quite a shock since my previous two semi-autos were a FAL and a 30 Carbine (both piston guns). It must have taken me an hour to get everything clean again!

    How do you guys put up with it?

    Anyway, I think I am going to put the flash hider back on the AR and restrict the can to the bolt action rifle.
    Coming from shooting 5.56/9mm suppressed for the last few years, you just allocate more time to cleaning. That's it. All of my BCG's are now nickel boron or black phosphate so just hit em with the degreaser and wipe. Much easier than the standard BCGs. Microslick stuff is coming out too.

    I don't think I've ever seen an accuracy decreased because of dirty rounds in the mag, I wouldn't worry about it.

    Edit - also look into an adjustable carrier. I have a Bootleg carrier on the way for my 12.5" suppressed 5.56 I'll try before buying more for the 6.5G rifles.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •