I’m thinking about a longer range gun. Will you guys please let me which caliber of the two you might choose?
With 6.5 I get AR15 platform compatibility for sure and supposedly its as good or better than 308 out 1000 meters - but is it really that good?
i’m sort of finishing up asking myself the same question, although i’d been trying to decide between the 6.8 and 308. the 6.5 seems to perform better than 6.8, but parts and ammo are even less available and more expensive than 68, so 6.5 was immediately dropped from the running for me.
really, they’re not too comparable… the 65s and 68s stay within the realm of the traditional ar15 size and configuration, whereas the 308s require totally different receivers, stocks, tools, etc. plus they’re bigger and heavier, and ammunition capacities are smaller and heavier. the only comparable feature is the ability to reach out farther.
all the same, i’ve decided to go ahead and shoot for an ar10. i’ve never done one, and it would be interesting to build something that’s not just a longer or shorter barreled version of the m4. i also like the fact that it takes me from a small calibered assault weapon to a battle rifle with a huge selection of horribly deadly factory loads to chose from.
i’ll probably do a 6.8 at some point in the future, but for now i’m set on a 30 cal.
The 6.5 is superior ballistically to the 308 (for paper / target shooting), but is going to be more expensive & much, much harder to find parts & ammo for. If you are considering a 6.x caliber bullet for long range, and aren’t wedded to the AR15 platform, I’d go for a 260 / Creedmoor / etc. Same bullets + more powder = better long range performance than either the Grendel or 308.
Having said all that, I have my heart set on a Grendel as soon as I can afford one… :D:D
Guys I was the very same way. Not too sure of which one to choose but after some extensive research the 6.5g is definitely the way to go. The 6.5g is probably the most versatile round you can get. You can use it for close quater,mid range,or AT&T someone from far far away. Right now I’m working on 6.5g SPR build. If guys are interested I’ll keep you posted.
Please keep us posted. I (like most of this group appears to be) have been mulling over my next build and I am leaning toward the 6.5g. I want a rifle with the range of a tactical rifle, but the flexibility of a main battle rifle. For that reason, I believe the 6.5g would by my choice. I understand that the economics and variety of ammo arguments for .308, but it just seems to me that a flatter shooting round is a better round.
Instead of a .308, I would consider a .300 Win Mag if I were going with a dedicated tactical rifle. The ammo is more expensive, but the ballistics (at least from what I read) are better.
My understanding is that the .300 Win Mag will eat up your barrel pretty quickly if you do shooting of any volume with it. Its a great distance round and a great round for hunting for those who break out the rifle when deer season rolls around and don’t do a ton of shooting. If you would be planning on doing any sort of regular shooting in numbers, I would steer away from that particular round, but that is just me. YMMV on this one but I have talked to quite a few people who have reported that the .300 Win Mag is extremely hard on barrels. Sweet shooting round though, there is no doubt about that one.
As for the remainder of the conversation, I too have been mulling over this decision for some time and have come down on the side of the .308 versus the 6.5 for a variety of reasons. Ability to find parts and ammo is one of them and is a very important one. The other for me is that I already have a 5.56 M4 so if I am going to step up to a larger and longer range round, I might as well go all the way with it. If you look at the actual data comparing the 6.5 and the .308, you will see that the differences in distance performance are pretty minimal unless you are getting way way out there. For me personally, I can’t see a time when I am going to need to take a shot over 600 meters so the fact that the 6.5 might shoot a little flatter at a 1000 meters doesn’t mean that much to me. For others, it might be important. In addition, if you reload, you can close that gap pretty quickly anyways. Speaking of reloading, material is going to be much easier to get for the .308 than it will the 6.5 for some time to come.
If I just getting into AR’s and was going to buy only 1, and everything else was equal, I would go with the 6.5 hands down. It seems to be the best amalgam of size, weight, accuracy, impact, and distance performance that has come out in terms of commercial ammunition for the AR platform. Since I am not planning to own only one, that argument is a bit moot for me. As it stands, I am eagerly awaiting the LMT 7.62 platform and will most likely snatch that up at my earliest opportunity. At that point, all of my AR needs will be taken care of for some time with the exception of accessories, getting the paperwork done for SBR, etc…
Good thread!
I’m a fan of the 6.5G and have two myself. The component situation can be a problem, but you can form 6.5G brass from 7.62x39 brass which is sometimes easier to find and cheaper. Hornady will be a new option for 6.5G brass in late '09or early '10 with more competative pricing than the Lapua brass. With that said the 6.5G Lapua brass lasts quite a long time.
If you want something that will handle the longer heavier bullets (130-140gr) better than the 6.5G look into the 6.5 Creedmoor. While Hornady is the only company that makes 6.5 Creedmoor brass. the Creedmoor brass can be formed from 308 or related brass. The 6.5 Creedmoor factory ammo performs well and even leaves some room for improvement.
How does the Creedmoor differ from the .260 Remington?
http://demigodllc.com/articles/6.5-shootout-260-6.5x47-6.5-creedmoor/
Good write up lots of info.
Thanks.
I plan to go with the 6.5 when I build my long range shooter.
I went with the 6.5, not that I have a place to shoot the exteme ranges it is capable of, but more because it really interested me, plus I can switch uppers and lowers around for different configurations.
That said I am glad I went this route. The other day I fired about 250 rounds and cannot see doing this with a .308 or larger caliber.
I’m currently building a 6.5 Grendel AR, not for the use to which you’d put your rifle, but the 6.5G is a very good 1000 meter cartridge. It is more accurate at that range than the 7.62NATO.
With 6.5 I get AR15 platform compatibility for sure and supposedly its as good or better than 308 out 1000 meters - but is it really that good?
Yes, in my opinion, it may be optimal for the AR-15 platform as far as range and power are concerned. To get more power you must either go to a larger platform, such as the AR-10, or substantially reduce magazine capacity, such as the .458 SOCOM or .50 Beowulf.
Although there aren’t as many sources for 6.5G ammo as there are for 5.56NATO, there are already at least four manufacturers making ammo/brass in this caliber. Lapua, Wolf, Black Hills (exclusively from Les Baer), and Hornady.
In comparison, try finding any of the short or super short magnums; or in my case, a source of 6.5 Remington Magnum ammo and brass. There’s only one manufacturer, Remington and that’s after 40 years of availability.
I think the 6.5G is cooking along very nicely, it’s a good choice.
I have an AA 24" barrel that I hope will be able to use out to 1,000 yards. Should be a lot easier on my shoulder than my .308 bolt gun.
I love the 6.5G—you can probably tell that by my signature line 
.308 does have its place—it’s a big powerful freight train but Grendel rds start to have better performance at 500yds over .308 rds. I like my for hunting, as it’s going out tomorrow morning early, and I don’t have trouble finding reloading supplies for it. Personally I’d take a mag full of grendel over .308—how much does an AR10 cost to build anyway?
I’m building a 6.5 myself. I simply like the smaller size and weight of the AR-15 platform.
I havea 24" Grendel, other than the .22 calibers it is the only gun I have that I can go out and shoot a hundred or so rounds and not have a sore shoulder. I like it so much I have parts ordered to build a 16" carbine.
I don’t think the data supports a blanket statement like that. The .308 is a much bigger cartridge with much more powder capacity (and recoil!) than the 6.5 Grendel.
Only in the very narrow sphere of comparing a potential 6.5 Grendel “military” sniper load such as the Black Hills Ammunition 6.5 Grendel 123 SMK (analogous to 5.56 Mk262) with the standard U.S. Army sniper 7.62x51 loads of 168 SMK M852 and 175 SMK M118LR does the 65G very slightly edge them out in drop and wind drift.
For how compact it is and considering the fact it works within the AR platform, the 6.5 Grendel is beautiful. But the .308 is truly a step above it for launching bigger chunks of lead at greater velocities, albeit with the recoil penalty.
John
I agree with Grendelizer
How about comparing Lapua ammo to Lapua ammo not Lapua 6.5 match ammo to military 308 ammo?
Both of these are Factory Lapua loads.
6.5 Grendel 123gr Lapua at 2600fps from a 26" barrel- Zero at 300yds drop at 800, 169", drift 53", drop at 1000 335" drift 89"
308 Win 155gr Lapua at 2820fps from a 26" barrel- Zero at 300yds drop at 800, 148, drift 51", drop at 1000yds 294" drift 87"
Just to make it easy the 308 has 21" less drop than the 6.5Grendel at 800 yds and 41" less drop at 1000yds.
Just to make things interesting 6mmBRX 105 Lapua at 3100 fps Z at 300 drop at 800 115", drift 42", drop at 1000 228 drift 71
Same ballistics program with the same settings using data from Lapua
Except that my comparison is between Black Hills 6.5 Grendel match ammo with Black Hills 7.62x51 match ammo, all using Sierra MatchKings in their respective calibers, so the comparison is valid, as far as it goes, and is about as apples-to-apples as one can get.
John