6.5 Grendel Bartlein barrel profile for 18" AR 15?

[MichiganMitten]

I'm looking at having a Bartlein barrel made for me. The question came up as to what profile would be best for a Recce/SPR type build? At first, it was suggested that I go with a .875 gas block diameter and have the barrel fluted to increase the overall rigidity. I loved the idea of slightly increasing the weight, but perhaps increasing the inherent accuracy over a thinner barrel with a .75 gas block.

Now I tried to find a handguard for an AR 15 that would accommodate the minimum inner diameter of an SLR 8 adjustable gas block. SLR has that listed as 1.35" ID required for the SLR 8... Unfortunately, every single handguard I looked at, had 1.3" inner diameter listed.

So, back to the drawing board. I was hoping someone more knowledgeable than me could suggest the best route to go for an accurate barrel profile for an 18" rifle gas 6.5 Grendel (.75 gas block?), without creating a monster in weight. I was thinking of having this spiral fluted as well.

Thanks!

 

[Torchy]

I know this may not be a popular opinion, but choose a different caliber. I have literally seen more people with bad luck than good luck with that cartridge.

I personally tried 3 different Bartleins with 2 different smiths, all with matched bolts to barrel and all shot horribly. Had another buddy with same problem as me (they wouldn't group with all kinds of different combos). Have 2 other buddies that have Grendels and they are lasers. Have one last buddy that kept breaking bolts with his (3 total then sold it). I can recommend who to use and not to use but IDK if that'll get me in trouble.

Craddock himself will tell ya he doesn't love the cartridge but he'll do it for ya (which I love that about him).

For profiles I like the 875 and 750. Did all 750's on mine but if I did it again I'd go 875. Oh and fyi fluting actually reduces rigidity given the same barrel diameter. It's more for weight reduction. That said a fluted 875 could be cool. You'd have more rigidity than a 750 but not all the weight of a full blown 875. And def yes on the rifle gas. Heck if you could score a +1" or +2" that'd be a added bonus.

Sadly I got completely out of the caliber. Hope this helps and don't hate me

 

[mheimer_45]

What type of handgaurd are you looking for. YHM has several listed with an inside diameter of 1.75”. I have a few. They are rock solid.

And the Grendel is a fantastic cartridge.

 

[MichiganMitten]

I'm looking for a super light 15" M-lok handguard. I WAS looking at the aero Atlas S-one. However, that has the 1.3" ID. If there is a nice lightweight handguard that has an ID > 1.35", then that would be the ticket that would allow me to use the .875 gas port.

That being said, I'm still not sure that this is the correct direction to take this barrel? Perhaps slimming the barrel down to .75" for a rifle length gas would be more ideal for strength / weight ratio... I don't know.

 

[hitman]

Look at Satern or Lilja also. I have a Satern and it is awesome and only $ 450 with a bolt. Paul has told me the same thing though about the Grendel.

 

[MSTN]

This is a Bartlein 6.5 Grendel barrel from Craddock Precision, a one-hole gun at 100 yards. This Seekins forend has plenty of room inside.

 

[strike33]

Larue Grendel with a Craddock Bartlein Spr 18" barrel

 

[bobke]

Well...where to start? First off, the Grendel has been one of the easiest, most flexible and accurate gas gun cartridges to load for, in my experience with 7 different Grendel’s. There are many options available in barrel profiles, either off the shelf or tailored to your needs/wants. Are you wanting an adjustable GB because you’ll be shooting suppressed, wanted to work with different handloads or just to have some flexibility?
My first pure custom Bartlein Grendel was spun up by Bob Reynolds of Templar Custom. He recommended an .800 profile in front of GB, as he said he’d been told long ago that .800 assured enough rigidity for an accurate result. Okay. He also sold his own low profile hand guard-very similar to a current BCM. Great-only issue being couldn’t fit an AGB under guard. I agreed, with hesitation. I’d have to remove the GB to tell you what size gas port was drilled, but in combination with correct buffer and springs, is a very soft shooting gun, and exceptionally accurate as you’d expect from a Bartlein.
All that said, I have a couple of Satern cut rifled barrels with .875 AGB and Mega/SLR hand guards, and don’t care much about their weight as they are very accurate barrels. Also have JP, Lilja and Wilson Combat .750 barrels with AGB and smaller hand guards, and they are a bit lighter/handier, very accurate, though in sustained strings of fire, they do heat up faster. I like the smaller HG’s, but have also run the Seekins HG’s, and as MSTN noted, they have ample room for either .750/.875 GB’s. Clamp on’s need a bit more clearance than set screw style.
You’ve got lots of options to exercise, just need to decide on priorities and then hit it.