BOTW: DJ's 6.5 Grendel Pistol Build

Tom R
by Tom R

The fifteenth Installment of Build of the Week was contributed by DJ. I personally have no experience with 6.5 Grendel. One of the things I am enjoying about this series is seeing the variety of not only modifications but platforms. DJ has provided one of the more detailed write-ups for his build.

In any case, keep the submissions coming in! We are publishing them in the order in which they were received (with the exception of a single person submitting back to back–those will get spread out).

You can submit your own build at

6.5 Grendel is often thought of as a cartridge with a niche in long-range shooting with high BC projectiles. That is why my first foray into the cartridge was an 18″ mlgs AR platform designed for precision shooting. But then I got the itch to build a versatile pistol that would be a compact but capable performer in a home defense or truck gun role.

Unwilling to accept the ballistic penalty 5.56/.223 suffers when fired from a short barrel, I decided to pursue an alternative cartridge, particularly .300 Blackout, 6.8 SPC or 6.5 Grendel. When I compared the ballistic performance of those three cartridges, I realized that 6.5 Grendel is vastly underappreciated as an option for short barrels. It outclasses .300 BLK all around (except of course ability to fire heavy subsonic projectiles) and is effectively the same as 6.8 SPC until the 6.5 Grendel starts to pull ahead after I believe a couple hundred yards. Since I already had 6.5 Grendel mags and didn’t want to add a new cartridge to my collection, the choice was easy.

I completed the build with more than a little help from the fine folks at the 6.5 Grendel Forum (, which has an amazing group of civil and knowledgeable members and is a great resource for anyone interested in the cartridge. I am very pleased with the build, which I put together with a focus on achieving high quality and reliability at a reasonable cost. Without further adieu, here is a list of the components/specs:

  • 12″ carbine length gas system 1:8 twist 5R rifled barrel custom made by Faxon Firearms for a Grendel Forum group buy.
  • Ergo low profile adjustable gas block.
  • WMD NiBx bolt carrier with nitrided 6.5 Grendel Bolt sourced through Bear Creek Arsenal.
  • BCM Gunfighter charging handle.
  • BCM pistol grip (Mod 0 I think).
  • Magpul Mlok vertical grip.
  • 12″ UTG pro Mlok free float handguard.
  • Magpul BUIS.
  • Holosun HS503C red dot.
  • NiB enhanced mil-spec trigger.
  • KAK shockwave brace and buffer tube (I’ve been running an H1 buffer and standard carbine spring).
  • Krink style brake (essentially Noveske Flaming Pig knockoff) which is very effective in taming recoil and muzzle blast.
  • Monstrum tactical light/mount and remote pressure pad (remote switch wire cut and soldered to more reasonable length).

I think that about sums it up!

Comment below to ask DJ questions about his build.

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Tom R
Tom R

Tom is a former Navy Corpsman that spent some time bumbling around the deserts of Iraq with a Marine Recon unit, kicking in tent flaps and harassing sheep. Prior to that he was a paramedic somewhere in DFW, also doing some Executive Protection work between shifts. Now that those exciting days are behind him, he teaches wilderness medicine and runs an on-demand medical staffing business. He hopes that his posts will help you find solid gear that will survive whatever you can throw at it--he is known (in certain circles) for his curse...ahem, find the breaking point of anything.You can reach him at tom.r AT or at

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4 of 85 comments
  • Brut Faberge Brut Faberge on Oct 18, 2018

    So are the folks being willfully ignorant about the status of this weapon anti-2A trolls or idiots?

  • RetiredSOFguy RetiredSOFguy on Oct 31, 2018

    Nice build. I was intrigued by Fortier's article on a short barreled 6.5G in one of the fairly recent gun mags and glad to see this.

    Not trying to be an ass, but is that vertical fore grip going to get you in trouble with ATF, seeing as how this is a pistol and not an SBR? I'm not a lawyer, just offering that up so you don't accidentally run afoul of some dish*t ATF guy like recently happened up in northern Ohio. You may want to consider an angled fore grip or some other option. Just a thought.

    • See 1 previous
    • RetiredSOFguy RetiredSOFguy on Nov 06, 2018

      @Dcommoncents Yeah, after your reply I checked out some of the comments.

      Interesting stuff and I'd kind of blown past the 26" OAL mentioned in your writeup, frankly because I didn't have the sight picture on the "firearm" (I'd just see that ref'd on the non-SBSes and the Franklin Armory smooth bore thing). I'm trying to brush up on that now at the ATF website. Interesting stuff for sure.