6.5 Grendel v .300 Blackout

newguy2k3v2

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I'd say Grendel can do more things well than any other round from an ar-15. Factory 123gr does 2275-2300 from 12.5 Lilja and BA barrels
Biggest cons I see are feeding/magazine issues which not everyone has them though.

6.8 can be pushed harder and give more energy inside 400 or so, barrel length being equal. Mag situation seems better. Lots of hunting bullet and factory ammo options.

300blk makes sense vs anything else in <10" barrels and 200yds and in. It's cheap and easy to take up and reload for people already invested in 5.56 and 30cal. To me the subsonic ability is more fun/gimicky than practical.
 

5RWill

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Then 6.8 SPC is your cartridge for about a dozen different reasons. Not going to even get into it here, the Grendel fanatics will smell the blood in the water and start posting page after page of 500 yard to 1500 yard software stats despite you saying 100 to 300 yards.

-Stooxie
I'm not a fanatic and will just disagree respectfully. Less i'm missing something 12.5" SPC can push a 110gr .277 projectile at 2300ish? Case capacity is roughly the same OAL is roughly the same, the only real draw back with the grendel seems to be the x39 case taper and needing mags for it. From a reloading standpoint i'm just not sure what the 6.8 spc offers over the 6.5 grendel again less i'm missing something? I've seen someone post this argument before but didn't elaborate on why i would be better off with the SPC. What am i missing? I'd rather have the 123gr or 129gr SST at 2300 than a 110gr round at 2300. The SPC does have the 145gr ELD-X but it's unlikely it can be pushed to any decent speed at that barrel length, less i'm severely underestimating the benefits of reloading for it.

FWIW this is the hide not ARF i doubt they'll come after you lol.
 

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I'm not a fanatic and will just disagree respectfully. Less i'm missing something 12.5" SPC can push a 110gr .277 projectile at 2300ish? Case capacity is roughly the same OAL is roughly the same, the only real draw back with the grendel seems to be the x39 case taper and needing mags for it. From a reloading standpoint i'm just not sure what the 6.8 spc offers over the 6.5 grendel again less i'm missing something? I've seen someone post this argument before but didn't elaborate on why i would be better off with the SPC. What am i missing? I'd rather have the 123gr or 129gr SST at 2300 than a 110gr round at 2300. The SPC does have the 145gr ELD-X but it's unlikely it can be pushed to any decent speed at that barrel length, less i'm severely underestimating the benefits of reloading for it.

FWIW this is the hide not ARF i doubt they'll come after you lol.
The 6.8 will propel the same weight bullet out of the same length barrel 100fps faster than the Grendel. It's right on Hornadys website, the only thing you need to notice is fps on a Grendel(123sst at 2580) is from a 24" barrel and from the 6.8(120sst at 2460) it was shot out of a 16" barrel. There is roughly 200 fps difference between a 16 and 24" barrel.
 
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5RWill

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The 6.8 will propel the same weight bullet out of the same length barrel 100fps faster than the Grendel. It's right on Hornadys website, the only thing you need to notice is fps on a Grendel(123sst at 2580) is from a 24" barrel and from the 6.8(120sst at 2460) it was shot out of a 16" barrel. There is roughly 200 fps difference between a 16 and 24" barrel.
When i looked at 12.5" chrono results it sure didn't seem that way. Though admittedly they were factory rounds. 12.5" 110gr 6.8 spc was a hair over 2300 while the 123gr SST was at 2300 with the grendel. You're saying reloading you can take advantage of slightly more case capacity? It's literally equal to 1.9gr more H20 capacity. The only bullet i'd want to run with the 6.8 SPC is the 145gr ELD X which getting again getting that bullet weight to those speeds in either case would be difficult.


Is reloading where the 6.8 can really stretch it's legs?
 

Stooxie

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When i looked at 12.5" chrono results it sure didn't seem that way. Though admittedly they were factory rounds. 12.5" 110gr 6.8 spc was a hair over 2300 while the 123gr SST was at 2300 with the grendel. You're saying reloading you can take advantage of slightly more case capacity? It's literally equal to 1.9gr more H20 capacity. The only bullet i'd want to run with the 6.8 SPC is the 145gr ELD X which getting again getting that bullet weight to those speeds in either case would be difficult.
It's like a disease, the only numbers that ever get quoted for 6.8 are SSA's anemic loads. Literally one of a dozen manufacturers. Please take a look at Federal Fusion, Hornady SST, or S&B if you want a sample of much faster factory loads.

We've been around the block 1000 times on this on various forums. 6.8 SSA fart loads get compared to someone's hotter-than-hell 6.5G hand loads. No matter how much chrono data you post, the G can never lose. It's like Democrats saying Trump is guilty. Nothing you say changes it.

-Stooxie
 

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When i looked at 12.5" chrono results it sure didn't seem that way. Though admittedly they were factory rounds. 12.5" 110gr 6.8 spc was a hair over 2300 while the 123gr SST was at 2300 with the grendel. You're saying reloading you can take advantage of slightly more case capacity? It's literally equal to 1.9gr more H20 capacity. The only bullet i'd want to run with the 6.8 SPC is the 145gr ELD X which getting again getting that bullet weight to those speeds in either case would be difficult.


Is reloading where the 6.8 can really stretch it's legs?
First off unless you want to fool yourself use comparable bullets. I see people comparing 90g flat base 6.8 loads to 123gr boat tails out of a Grendel to prove the Grendel shoots flatter. That is only fooling idiots. Hornady makes ammo for both the 6.8 and 6.5 and similar weight bullets, they load to the same percentage of max factory safe operating pressure. All of the info is there on their site for all to see. The one thing Hornady failed to do was test both out of the same length barrel.
As for reloading yes the 6.8 can handle the pressure and gain even more velocity over the Grendel. As far back as 2007 we were shooting 110gr bullets at 2800 out of 16" barrels. 120s around 2650.
 

5RWill

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It's like a disease, the only numbers that ever get quoted for 6.8 are SSA's anemic loads. Literally one of a dozen manufacturers. Please take a look at Federal Fusion, Hornady SST, or S&B if you want a sample of much faster factory loads.

We've been around the block 1000 times on this on various forums. 6.8 SSA fart loads get compared to someone's hotter-than-hell 6.5G hand loads. No matter how much chrono data you post, the G can never lose. It's like Democrats saying Trump is guilty. Nothing you say changes it.

-Stooxie
Noone has posted any 6.8 spc data with similar bullet weight/BC to prove otherwise, which is why i've been googling. Literally 2nd link is handloads of 120gr SST and it's right there with the grendel in the 2300s. Both at 12.5" of course. Which is why i proposed the question of reloads stretching the 6.8s legs, because to attain BC comparable for the 6.8 i gotta go 130-145gr.

First off unless you want to fool yourself use comparable bullets. I see people comparing 90g flat base 6.8 loads to 123gr boat tails out of a Grendel to prove the Grendel shoots flatter. That is only fooling idiots. Hornady makes ammo for both the 6.8 and 6.5 and similar weight bullets, they load to the same percentage of max factory safe operating pressure. All of the info is there on their site for all to see. The one thing Hornady failed to do was test both out of the same length barrel.
As for reloading yes the 6.8 can handle the pressure and gain even more velocity over the Grendel. As far back as 2007 we were shooting 110gr bullets at 2800 out of 16" barrels. 120s around 2650.
Is that not what i linked to? Both what i could find quick googling 120gr range with somewhat comparable weight/BC to the 123gr 6.5 out of a 12.5" barrel length. 12.5" will be the length i go with regardless of caliber chosen. Don't want a javelin once the can is on. What realistically could you expect from say a 145gr ELD-X from that barrel length?

Think i could squeeze an extra 100fps or so out of the 130s in a 6.8 over 130s/129 in the grendel?
 

Jmccracken1214

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How do the comparing loads look at 400-500 yards? Like the G and 308.. 308 is always faster at the muzzle but 400 out, it’s slower than the G
 

XLR308

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I'm not a fanatic and will just disagree respectfully. Less i'm missing something 12.5" SPC can push a 110gr .277 projectile at 2300ish? Case capacity is roughly the same OAL is roughly the same, the only real draw back with the grendel seems to be the x39 case taper and needing mags for it. From a reloading standpoint i'm just not sure what the 6.8 spc offers over the 6.5 grendel again less i'm missing something? I've seen someone post this argument before but didn't elaborate on why i would be better off with the SPC. What am i missing? I'd rather have the 123gr or 129gr SST at 2300 than a 110gr round at 2300. The SPC does have the 145gr ELD-X but it's unlikely it can be pushed to any decent speed at that barrel length, less i'm severely underestimating the benefits of reloading for it.

FWIW this is the hide not ARF i doubt they'll come after you lol.
I think it just really comes down to what you want to do with it and like anything else picking the best tool for the task at hand.
Both are very capable when used in the primary role most of us choose them for which is hunting inside of 350 yards.
Just as a data point my 68spc 120sst load with AR-COMP out of a 20" ARP barrel averages 2730fps.
 

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How do the comparing loads look at 400-500 yards? Like the G and 308.. 308 is always faster at the muzzle but 400 out, it’s slower than the G
That depends on the bullets chosen. Most Grendel guys will choose the best possible bullet for the Grendel and then choose a flat based poor performing bullet for the 308. Try a .308 155gr Berger Hybrid or Hornady ELD using similar length barrels.
 

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Noone has posted any 6.8 spc data with similar bullet weight/BC to prove otherwise, which is why i've been googling. Literally 2nd link is handloads of 120gr SST and it's right there with the grendel in the 2300s. Both at 12.5" of course. Which is why i proposed the question of reloads stretching the 6.8s legs, because to attain BC comparable for the 6.8 i gotta go 130-145gr.



Is that not what i linked to? Both what i could find quick googling 120gr range with somewhat comparable weight/BC to the 123gr 6.5 out of a 12.5" barrel length. 12.5" will be the length i go with regardless of caliber chosen. Don't want a javelin once the can is on. What realistically could you expect from say a 145gr ELD-X from that barrel length?

Think i could squeeze an extra 100fps or so out of the 130s in a 6.8 over 130s/129 in the grendel?
You can't use a 145eld-x, the bullet is too long. A Berger 130 Classic Hunter is about as long as you can use in a 6.8 and it still fit in the mag. 2450-2475 out of a 12.5" .
A Grendel will only push a 123gr to around 2550-2600max with hot handloads out of a 20" barrel, 200fps less with a 12.5" barrel 2350-2400 and notice that is using a bullet that is 7gr lighter. If you choose a 130 for the Grendel you will loose another 70fps.
A 6.8 130 Berger has apx the same BC as a 6.5 123gr ELD.
One other thing to consider, when bullets slow down to the point they will not expand that is really the max effective range. Big heavy 6.5s made for a 260 Rem or 6.5 x55 may not expand very well shot out of a slower Grendel.
BTW I'm not getting figures from google, I've been shooting both the G and 6.8 since 2005.
 

5RWill

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You can't use a 145eld-x, the bullet is too long. A Berger 130 Classic Hunter is about as long as you can use in a 6.8 and it still fit in the mag. 2450-2475 out of a 12.5" .
A Grendel will only push a 123gr to around 2550-2600max with hot handloads out of a 20" barrel, 200fps less with a 12.5" barrel 2350-2400 and notice that is using a bullet that is 7gr lighter. If you choose a 130 for the Grendel you will loose another 70fps.
A 6.8 130 Berger has apx the same BC as a 6.5 123gr ELD.
One other thing to consider, when bullets slow down to the point they will not expand that is really the max effective range. Big heavy 6.5s made for a 260 Rem or 6.5 x55 may not expand very well shot out of a slower Grendel.
BTW I'm not getting figures from google, I've been shooting both the G and 6.8 since 2005.
That is certainly more appealing. What's a good barrel supplier for a 12.5" 6.8 SPC? Don't wanna have to grab a blank and turn it down as i'm not looking to spend that much. That is the argument i've been looking for, that's solid results worth considering 6.8 spc over the 6.5G considering what i'm doing.
 

AEROMechanic

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You're retarted
12.5" Grendel 123s @2330
16" Blackout 110s @2400

Bigger hole more faster more better

And that's probably reloading for the 6.5 short and weak. Everyone likes to compare their wonder cartridge with hot reloads to mild accurate factory ammo for the competitor
Less penetration with the BO. BC's matter
 

AEROMechanic

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Then 6.8 SPC is your cartridge for about a dozen different reasons. Not going to even get into it here, the Grendel fanatics will smell the blood in the water and start posting page after page of 500 yard to 1500 yard software stats despite you saying 100 to 300 yards.

-Stooxie
I'm a Grendel guy and I disagree with your above statement. If he's only shooting 100-300 yards then 5.56/.300 BO/6.8SPC/6.5 Grendel are going to kill whatever you're shooting at, equally as dead. So with that being said you might as well stay with 5.56 shooting heavies (75-77gr).
 

346ci

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That is certainly more appealing. What's a good barrel supplier for a 12.5" 6.8 SPC? Don't wanna have to grab a blank and turn it down as i'm not looking to spend that much. That is the argument i've been looking for, that's solid results worth considering 6.8 spc over the 6.5G considering what i'm doing.

He has a 5R in stainless also.
 
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