Page 1 of 2 12 LastLast
Results 1 to 10 of 12

Thread: School me on a 6.5 Grendel build

  1. #1
    Join Date
    Nov 2007
    Location
    Georgia, USA
    Posts
    3,818
    Feedback Score
    0

    School me on a 6.5 Grendel build

    I've gathered some parts for a 6.5 Grendel build. My goal is to build a light weight 16" carbine. Here are the parts that I have so far:

    All parts are from Alexander Arms including the upper and lower receivers. They are both marked 6.5 Grendel which an anal retentive person like me can really appreciate. I've built several 5.56x45 AR-15's from parts, so I understand the general process. The thing that I want to avoid are pitfalls that are specific to this cartridge. Do I need any other parts that are 6.5 Grendel specific? Is there anything different about the assembly or tools that are required? Thanks in advance.

  2. #2
    Join Date
    Jun 2009
    Location
    Allentown, PA
    Posts
    3,422
    Feedback Score
    58 (100%)
    There should be no difference in building that rifle then any other. As far as your picture, the only thing i see missing that isn't like building any other 5.56 rifle is the muzzle device which has a different thread pitch than a 5.56 rifle.
    "Perfect Practice Makes Perfect"
    "There are 550 million firearms on this planet. That's one firearm for every 12 people. The question is... How do we arm the other 11?" Lord of War.
    "I predict future happiness for Americans if they can prevent the government from wasting the labors of the people under the pretense of taking care of them." Thomas Jefferson

  3. #3
    Join Date
    Sep 2010
    Location
    Charleston, SC
    Posts
    35
    Feedback Score
    3 (100%)
    Yep, just looks like you need the muzzle device. I recommend Maxim Firearms. Hit them up on Facebook and message Frank Sabatano. Common thread is 9/16x24 on the Grendel which doesn't have as many choices. If yours is 5/8x24 you can use just about any .30 cal device you want.

  4. #4
    Join Date
    Nov 2007
    Location
    Georgia, USA
    Posts
    3,818
    Feedback Score
    0
    The description of the barrel lists the muzzle as being threaded 9/16x24 RH. I don't do Facebook. CNC Warrior has the one pictured below which looks pretty decent.


    Any other sources?

  5. #5
    Join Date
    Nov 2010
    Location
    MI
    Posts
    3,516
    Feedback Score
    22 (100%)
    That barrel doesn't look very light weight.

    The build may end up heavier than anticipated.

    Barrel, bolt and magazine are the only special parts for a 6.5 or 6.8 build.
    Black River Tactical
    BRT OPTIMUM Hammer Forged Chrome Lined Barrels - 11.5", 12.5", 14.5", 16"
    BRT EZTUNE Preset Gas Tubes - PISTOL, CAR, MID, RIFLE
    BRT Bolt Carrier Groups M4A1, M16 CHROME
    BRT Covert Comps 5.56, 6X, 7.62

  6. #6
    Join Date
    Jan 2011
    Posts
    3,655
    Feedback Score
    6 (100%)
    Make sure the bolt is correct, should not be a problem if AA.

    Check to make sure the barrel and upper receiver both have the same feedramps. All the AA I've seen has been M4 style.

    Nothing specific to worry about for Grendel other than what has been mentioned.

    I'd probably get a H2 buffer, but its not critical.

    Don't go crazy on barrel torque, normal 30-35 lbs is fine

    I've not seen a Grendel that did not shoot well that had a saami chamber, and AA will be saami for sure.


    (Typo corrected, saami Grendels a shoot great!!!!)

    Sent from my PRC-104 using phonetics
    Last edited by pinzgauer; 03-13-17 at 14:00.

  7. #7
    Join Date
    Nov 2007
    Location
    Georgia, USA
    Posts
    3,818
    Feedback Score
    0
    Quote Originally Posted by Clint View Post
    That barrel doesn't look very light weight.
    The build may end up heavier than anticipated.
    I'm thinking the same thing, but it's AA's lightweight barrel. We'll see.

    Quote Originally Posted by pinzgauer View Post
    Check to make sure the barrel and upper receiver both have the same feedramps. All the AA I've seen has been M4 style.
    They do.

  8. #8
    Join Date
    Dec 2012
    Location
    Rocky Mountains
    Posts
    386
    Feedback Score
    0
    I've built several with that exact barrel, have another in the works for a friend. They are very lightweight since there are so many flutes.

    Yes, there are some nuances to building these that can help you avoid problems right off the bat.

    Biggest ones are chamfering the ejector and tuning the extractor.

    For accuracy, I lap the receiver face (although AA receivers already come this way), bed the barrel extension into the upper, and seal the gas block and tube.

    I also de-edge, blend, and polish the feed ramps so there is no chance for meplats to hang up on the ramp edges. I basically hand-fit the guns.

    Use 60ft-lbs of torque or more with this caliber on the barrel nut. I use zero torque on the flash hider. An Alexander Arms A2 is what I prefer with the 9/16x24 threads.

    You'll notice that there are some unique steps in the profile of this little AA barrel at the gas block journal, but using a low profile gas block works just fine with it, even though there will be a slight gap in the front. I seal the block to the journal after measuring port locations and testing gas circuit, so no issues.

    There is a bunch of work I do on the bolt to reduce brass shavings. If you look at Hellbender's gunsmithing thread, you'll see what I do.

    Basically, most of what I do is unrecognizable to the DIY AR15 builder. My guns work out of the gate, and are always very accurate.

    These barrels make for wonderful little AR15's. With an H2 buffer, it handles like a pussycat, because AA uses an optimum port size after years of testing. You don't need a muzzle brake at all. With common components, you'll end up with a 6lb gun without optics. That's with a 15" MI handguard as well.
    Last edited by LRRPF52; 12-24-15 at 10:36.

  9. #9
    Join Date
    Nov 2007
    Location
    Georgia, USA
    Posts
    3,818
    Feedback Score
    0
    It's been a while I know, but I'm going to move forward on this project after letting it sit in a box for over a year. I appreciate all the very helpful information that's posted here. I decided to go with an Adams Arms mid length piston setup. It kind of works out because I have a bolt, but need a carrier which the kit comes with. I'm not sure of the optic that I'm going to use yet. I have an extra Mepro M21, but I might go with something that has magnification in order to get more accuracy out of the setup. Other than the stock set, I'm down to needing the following parts:
    1) Charging handle assembly
    2) Backup sights
    3) Muzzle attachment
    4) Crush washer
    5) Barrel nut

    Before I round up the few remaining parts that I need, I have a couple of questions. I tried a regular crush washer and found that the internal diameter wasn't large enough. What do people usually do?
    Would I be correct to assume that a regular barrel nut would work?

  10. #10
    Join Date
    Nov 2007
    Location
    Georgia, USA
    Posts
    3,818
    Feedback Score
    0
    Does anyone know about the crush washer and barrel nut questions?

Page 1 of 2 12 LastLast

Bookmarks

Posting Permissions

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