The case for 6.5 SBR vs other calibers

[zekers7]

Everyone says the grendel is built for 18-20+" Barrels. My first build has a 18" barrel and is my favorite rifle to shoot.


Everyone bashes 6.5 in short barrel configurations but I cant find any fault in it.
A 11.5" Barrel will push a 123gr A-MAX 2175 FPS. What does a 120-123gr pill moving 21-2200 fps sound like? Thats correct: 7.62x39 and the blackout. The difference? BC. Roughly .290-.310 vs .510 in the grendel. I also give the 77gr the benefit of the doubt in the comparison below as its usually claimed to only reliably fragment down to 2200fps.


77GR Black Hills 223 - 16" @ 2683fps
Frag Threshold (2100 FPS): 250 Yards
Energy (700ft-lb): 275 Yards

77GR Black Hills 223 - 11.5"
no need for data. Its good to 50-100 yard MAX

125GR AMAX 300 Blackout 16" @ 2200 FPS although they usually test slower"
Expansion Threshold (1400 FPS): 350 Yards
Energy (700ft-lb): 250 Yards

123GR AMAX 6.5 Grendel 11.5" SBR:
Expansion Threshold (1400 FPS): 550 Yards
Energy (700ft-lb): 400 Yards


The 11.5" Grendel outperforms all other cartridges even in full length configurations. Im not including 6.8 SPC because I dont find it to be a relative round. I can get WOLF grendel rounds for .28/ea and practice all day long with it, as well as use the same bullets and powder to handload both it and my Creedmoor. 6.8 SPC is a fantastic round but nobody is throwing $0.75 plinking rounds downrange all day long. More power to you if you can.

[biodsl]

Welcome, zekers. I doubt you'll get any argument on this forum to your conclusion. If fact, this is exactly how Bill A. advertised his 10.5" upper when he sold one: AK-47 ballistics from a 10.5" barrel.

[stanc]

The 11.5" Grendel outperforms all other cartridges even in full length configurations. Im not including 6.8 SPC because I dont find it to be a relative round. I can get WOLF grendel rounds for .28/ea and practice all day long with it, as well as use the same bullets and powder to handload both it and my Creedmoor. 6.8 SPC is a fantastic round but nobody is throwing $0.75 plinking rounds downrange all day long.

No, they don't. Although your comparison is a trifle disingenuous, since you're comparing the very lowest price for 6.5 Grendel, but nearly the highest price for 6.8 SPC. The lowest price that ammoseek shows for 6.8 SPC "plinking" ammo is $0.63/ea.

And, there is reportedly a ready market for once-fired 6.8 brass, which could significantly reduce the price per round to near that of the Wolf 6.5 ammo. There is no such demand for fired 6.5 steel cases.

Finally, 6.5 Grendel SBRs are limited to after-market, 25-round, steel magazines. In contrast, 6.8 SPC has a SBR with 30-round polymer mags designed from the ground up specifically for the cartridge.

[A5BLASTER]

Thanks for the info sir, my next grendel will be sbr.

Dont have a dog in this fight stanc but aint that 6.8 sbr with the poylmer mags uniqe as in those mags will only work with that high end high dollar reciver set, if so that aint really a apples to apples comparision.

Either way they are both better then 223.

[zekers7]

Thanks for the info sir, my next grendel will be sbr.

Dont have a dog in this fight stanc but aint that 6.8 sbr with the poylmer mags uniqe as in those mags will only work with that high end high dollar reciver set, if so that aint really a apples to apples comparision.

Either way they are both better then 223.

Thats more what im saying. Im in no way bashing the 6.8 SPC. I think its a fantastic round and very similar to the grendel. I wont say its better or worse. Im saying they are both better than 223/556 or even the blackout.

Im just saying that a 6.5 SBR is nothing to laugh at. It has serious performance as im sure the 6.8 SPC does as well.

Grendel works better for ME because i enjoy the off-the-shelf .28 cent rounds and can handload both grendel and creedmoor with almost identical components minus the brass. I use XBR and 123gr amax for both. If the offered reloads of 6.8 were to drop in price by 50% I would seriously look at it too.

[stanc]

Dont have a dog in this fight stanc but aint that 6.8 sbr with the poylmer mags uniqe as in those mags will only work with that high end high dollar reciver set, if so that aint really a apples to apples comparision.

It's no different than comparing the price of 6.5 Grendel steel case ammo to the price of 6.8 SPC brass case ammo. 30-rd magazines is an option which is available for 6.8 SPC that is not available for 6.5 Grendel, even if you wish to make an "apples to apples" comparison of mags that only fit the standard AR15 magazine well.

[realtreehunter]

I'm new to this caliber and all but didn't I read somewhere that the 6.5 has better BC bullets than the 6.8 also? Thus making it a better round than the 6.8 for the same reasons that is better than the Blackout?

[bwaites]

I'm new to this caliber and all but didn't I read somewhere that the 6.5 has better BC bullets than the 6.8 also? Thus making it a better round than the 6.8 for the same reasons that is better than the Blackout?

Yes and yes. The only downside is that the mags are limited to 25 rounds presently vs 30 for the others. I haven't had to use it for multiple mag dumps, so I don't find that to be any restriction.

[ah1whiskey]

when you get into what fits the 5.56 mag well the 6.5g is the best GPC -- you can get more or less -- soo everything is a sort of trade off. yet the 6.5 gives up little in the SBR and holds up for the distance.

as far as mags i have got some mags that hold and feed more than 30 rounds of 6.5G-- but their not made for the 6.5g round-- yet they feed perfectly well so far.

i dumped a few mags of 32-33 rounds the other day through my truck gun upper. ran perfectly-- i rarely use them as their heavy and a bit odd looking-- generally i use a ASC with about 10-12 rounds that is enough for me to bust a couple hogs-- and have a few clean up shots--

[stanc]

as far as mags i have got some mags that hold and feed more than 30 rounds of 6.5G-- but their not made for the 6.5g round-- yet they feed perfectly well so far.

i dumped a few mags of 32-33 rounds the other day through my truck gun upper. ran perfectly-- i rarely use them as their heavy and a bit odd looking--

Why are you being so selfish? Let the rest of the Horde know the make and model of these wondrous magazines.

[Bravo Vector Tango]

RZE Unimag perhaps? i just actually saw these go for sale from one of my preferred online retailers.

I saw that there are some discussions here about it, but nothing recent.

[ah1whiskey]

no the ASC 30 rd for the 7.62x39

[stanc]

Interesting. Logic says that shouldn't work.

The 7.62x39 magazine's extreme curvature is all wrong for the 6.5 Grendel case taper.

And since the case diameters are the same, it shouldn't be possible to get 2-3 more rounds into the magazine.

[bwaites]

It might, though, because the top of those is straight, like the Grendel (and other AR) mags. If there is JUST enough slop, it might be possible.

[stanc]

I wonder if anyone else has ASC 7.62x39 mags, and can try to duplicate ah1w's reported results?