Home Forums Hunting & Shooting AR and Tactical Rifles 6.5 Grendel or .264 LBC help.....

I want to build an upper for my RRA lower. I originally wanted a 6.5 Grendel, but got real confused when I started reading about the .264 LBC. Seems to me the .264 only exists because AA wouldn't release their "proprietary" grip on the 6.5 G. So Les built essentially the same case, with a .005" smaller neck and a slightly different throat.

I heard that AA finally allowed their cartridge to be "commercial", so anyone should be able to chamber it, without paying AA a dime, right?

So now which one? Seems brass and dies are available for either, barrel makers seem to do one or the other cartridge, not both. Is it better, or more accurate to get a Grendel and run LBC ammo in it, or is the reverse true? Does the difference in neck diameter really make a difference, how?

I really want an ultralight upper, say 3 lbs, 20" and fluted, and I hope to get 1 MOA or better with handloads. Anyone have something similar, advice for a barrel source?

thanks.....

I had an Alexander Arms 6.5 Grendel. The chamber was cut with AA's "Compound" throat. What it was was No throat and the bullets would get stuck in the lands.

I replaced the AA barrel with a 6.5 CSS. The CSS is a Grendel with a .295 neck and a real throat similar to the LBC. My handloaded necks measure .291 so I have zero issues with the .295 neck.

There are plenty reports of bullets getting stuck in an AA Grendel chamber. My story is just one of many. If I had to do it over again, I would start with a CSS or LBC chamber and stay away from the Grendel. But that's just me, there are plenty of Grendel owners that think otherwise.

The simple answer to your question is they are the same and LBC ammo will work in the Grendel and verse-visa.

I have the Grendel but see no advantage either way. It is like the 223 Wylde chamber / 5.56 / 223. What is the real advantage of any of them? Not any in performance really but there are differences. LBC and Grendel ammo do work either way I have read.

I went with the Grendel from Saturn and have no ammunition problems or regrets. You'll get the usual tempest in a tea cup arguments for and against both of them. Now that AA has released this cartridge from proprietary status it'll probably become more popular than it is currently.

Terry

I'd go 243 LBS myself, the 6.5 is too slow. You've got bullets with awesome BC's and you can't make 'em sing 'cause they are limping along.

Thanks for the idea. I did run the numbers on the .243 LBC, and it just doesn't do what I want. I am really looking for energy on target, I am pretty sure the 6.5 adds another 100 yds of range over the .243, when you use say a 1000 ft-lbs. floor. It does leave the barrel faster though.....

FYI, a 6BR running a 105 8 twist will about equal a 6.5G/LBC at 400 yds, both can get there w/1K ft lbs.

I love the BR but would not want much less performance and the BR won't run in an AR. Other 6s will, but not sure how fast they run.

I am about to build a 6.5 grendel - if you look and call (I did), Model-1 sales has 20" 6.5 Grendel barrels (ER Shaw) for $235, and that is with barrel nut & gas block. they also have bolts for $50, and aluminum float tubes for $40 or $45

I see uppers complete for $80 on GB, and you have to figger a 7.62 birdcage FH and gas tube ($20 for both)so I am going to build one for use next year I think, and i will have about $350 less shipping in it....about as cheap as you can find

Hornady ammo is at CTD for $24 delivered

I'd risk a Black Hole barrel before I'd buy that Model 1

now for a dumb question. The 6.5's I see are usually longer barreled, I guess with rifle length gas systems? So if your wanting a 16 inch gun with a mid length gas system the 6.8 would seem to be the way to go? Looks like the 6.5's might have the upper hand in penetration, but I don't know for sure.

I looked at the 6.5's a tiny bit and am just curious, now that AA has relinquished his grip. I looked at the 6.8 quite a bit more but have found the 5.56 works very well with a 62 grain TSX on deer. On the other hand the 6.8 with the 85 grain TSX looks an awful lot like a 250 savage to me, and I keep thinking about if you were hunting a black bear with the fat they carry a 6.8 or 6.5 might produce a better drain hole.

why is that?

Mine ended up 18" with lots of fluting on a midlenth gas system. I didn't think to weigh it before the optics went on but it's a very accurate light setup. My advice would be to go ahead and spend some cash on the barrel. It's the heart of the rifle. Ammo for this gun, even if you build it yourself won't be cheap. You might as well try to get the most out of it. A lot of the cheap barrels aren't stress relieved properly and walk the shots as the barrel heats up.



Terry

AKA, maybe I am wrong, but I was under the impression the BR is not 'AR15' compatible, though options exists - at a lowered MV in same length bbls.

In the 6mm, I like the BR in bolt/single shots, but in an AR, would rather use a 6.5 bore, it will burn more powder sooner and I'd lean towards a shorter bbl for what I do, and a 6.5 has a better/higher expansion ratio.

http://www.6mmbr.com/gunweek068.html

Terry,

That looks like what I want. Who did your barrel? And if you let me know the total weight with the optics, and what optics you are running that would be usefully too.

Those that wonder about the running the 6 and 6.5 BR in an AR, I see AR 15 Performance in Colorado Springs, lists it as an option. I suspect the case head is just big enough that you have to physically modify the upper like on a mill or worse a grinder, to get things to flow with a BR case. That's just my guess, its best to talk to the guy who builds them. Of course there is Ditech who is having success modifying upper to run a whole series of WSSM based are cartridges on Mil Spec lowers. It sounds neat to me, but when I really read up on what people were saying that were running them, they kept coming up with new "new mods" to get them to really run they way they wanted. i.e. cutting out the front of mags, opening up the ejection port, etc. I decided I wanted a rifle, not a project. But I suspect with the number of people messing around with oversized cases in an AR, its only going to get better.

No problem, I'm in Chicago tonight but when I get home I'll weigh it. Now I'm just guessing but I bet Steve would do one just like mine except on a 20" tube if you were really set on a 20" barrel.


Terry

Hey Salmotrutta, I put the rifle on the scale this morning. With the optics included and the magazine removed it went 7lbs 12oz.

The build list:

1. Saturn 18" double fluted barrel. I'm not sure of the contour but it closely ressembles an SPR.
2. Badger gas block.
3. VLTOR flash suppressor.
4. 10" carbon float tube w/front swivel added.
5. Upper and lower are pretty much stock. It has a Magpul MOE grip, trigger guard and RRA MN trigger.
5. A.C.E. skeleton butt stock
6. Leupold 2.5-8X36 MR/T MK4 scope W/covers and a Burris P.E.P.R. 30MM mount.

I really like this scope. It replaces a NightForce NSX 2.5-10X32. The NF was a really good scope at the range but I didn't care for it in the field. The MR/T is very user friendly. It's bright, tracks well, holds zero and is one of the most non-critical scopes as far as eye placement goes that I've ever used. My only complaint is that I've really gotten too used to zero stop scopes and this one doesn't have that feature.



Terry

Very very nice. That is exactly what I want, with perhaps a bit longer tube! Thanks for sharing.

Nice rifle but I'd go with a Troy TRX so I'd at least have the option of a BUIS if desired. It is also nice to be able to run a light on any working gun.

I hear ya on the BUIS, but just didn't feel it was neccesary on this rig. It's a hunting/target gun, if it breaks I'll go home and get another scope. I also like the fact that I can hold the forearm on cold day's without my hand going numb from the cold aluminum I have one of those Troy tubes on another rifle and love it. Being thin they have a very nice feel to them.

Salmotrutta, I bet Steve at Satern would cut you a 20" with the same profile if you asked him to.

Terry