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 6.8 spc II vs 6.5 Grendel in a 20" Barrel...Don't hate on me I have looked all day!
futurerancher  [Member]
4/13/2010 5:20:15 PM
I am building my wife an all purpose hunting rifle based on the ar platform and I am really hoping that someone can help me out here. I have spent the better part of the day trying to find direct ballistic comparisons between the 6.8 spc II and the grendel in a 20" barrel. Furthermore, is the new and improved 6.8x43 going to close the gap between the two rounds? To narrow it down even more, I am looking at running a couple different bullets that fall between 120-130 grains. I really want to go with the 6.8 because of the industry support, but I feel like I am leaving to much on the table with the Grendel. I have read in several different forums about guys pushing the limits with the 6.8 rounds out of 20" barrel and hitting 2800+ fps. I need this rifle to be a solid 300 yard perfomer with the ability to take a follow up shot out to 400+ yards.

I really, really, appreciate all of your help gentelmen.
LedZeppelin  [Member]
4/13/2010 7:09:03 PM
Up close, within about 300yd there's not much difference between the two (6.8spc vs. 6.5g), however, beyond 300yd the 6.5 Grendel really takes over with it's higher BC bullets. Mark Larue killed an Elk (1 shot drop) at 405yd with a 6.5 Grendel a while back, and I've seen quite a few posts of deer killed up to 550 yd with the 6.5G.

If you don't reload and need the ammo availability, you might go with the 6.8, but if you reload you should be good to go with the 6.5. Lots of people over at 65grendel.com are getting sub MOA, even sub 1/2 MOA groups with handloads out of their AR's. I personally prefer the 6.5 to the 6.8, but I think I may be the minority.
MALT0SE  [Team Member]
4/13/2010 7:11:44 PM
What about the .450 bushmaster? I will soon have a lower that ill be dedicating to a non 5.56 build. This will be my deer/hog/all around game gun and I most likely will not be taking any shots longer then 2-300 yards
RealTeacher  [Member]
4/13/2010 7:14:07 PM
I cannot say much about the 6.5. I have never killed anything with one, and in fact, I have only fired one, one time.
However I have over 30 kills now with the 6.8 on deer and antelope, and I have several friends that own them too. In all we have accounted for over 60 kills with them, in several states.
I can tell you faithfully that the 6.8 SPC is a solid 400 yd killer on deer size game. My friend R.P. of Reno has the long range record of our little group at over 450 yds. I have killed several antelope with my rifles at 275 to 375 yds.
How would that compare to the 6.5?
I don't know.
But I can promise you, for up to 400 yds it's just fine. Why would it not be? If you look at the ballistics of the 257 Roberts (not the new "+P" loads, but the old original load Remington loaded for over 50 years) the 6.8 equals or beats it slightly.
The Roberts was and is a very good deer round.
I do get over 2800 FPS with my 20 rifle. That's actual measured velocity. It's not a 270 Winchester, but it's not asked to be either
I have used Remington 100 grain bullets, a few 115 FMJs, one Barnes 100 gr X bullet, and several of Hornady's new 100 grain open tip bullets.
The best killers so far have been the 100 gr Remingtons.
So........
6.5 shooters, it's your turn.
What think?
Tell us about how the 264" bullets work for you.
hi-tech-rancher  [Team Member]
4/13/2010 7:19:41 PM
Your questions are good ones. Since you clearly stated your need, it is easier to answer.

I don't have any ballistics charts to post for you, but after doing over 4 years of research and development on the 6.8, I can say that the Grendel will outclass the 6.8, if you must use 120-130 grain bullets. With longer barrels, and that weight bullet, the Grendel will hold its velocity much farther out. Those bullet weights do not work as well in the 6.8 because it is optimized to shoot shorter, lighter bullets, faster, and in much shorter barrels.

This isn't to say that the 6.8 does not perform well with 110 grain Accubonds in a 20" barrel, going 2800 FPS. But the Grendel will still carry more of its energy into the 400 yard range if you use longer bullets with BC's of .420's to .450's. The best BC 6.8 bullets are in the .300-.360's right now, but we are going to have some in the 100-120 grain range that may reach BC's of .400-.420, in the near future.

If I knew my shots were going to be very near 300 and likely into 400, I personally wold use a .308 and neither the Grendel or the 6.8. That is just my personal hunting ethic.I'm not familiar with "lightweight" 6.5 Grendels, but I would guess that they are being made.

But, if my shots were going to be most often at 100 or 200, and rarely up to 300, I would use the 95 grain Barnes TTSX, in the 6.8 or the 100 grain TTSX in the 6.5's, since it can expand out to 400 or so yards. ETA: opening velocity is 1600 FPS. The 6.8 is now shooting these 95's at 2950 out of a 20" barrel, so yes, the gap is closing, but not yet eclipsed, as its BC is only .296.

Hope this helps

jough43  [Member]
4/13/2010 7:34:37 PM
If you want good advice, re-read the above post. The 6.8 & 6.5 camps each have their proponents. My reasearch lead me to 6.8 and I am not disappointed. My first season out, I got 2 kills within 40 seconds. And even better better bullets will be available before next hunting season.
Gunwritr  [Team Member]
4/13/2010 8:19:12 PM
both are excellent choices.
I love my 20 inch Grendel but I know the 6.8 SPC also performs very well.
pavlovwolf  [Team Member]
4/13/2010 8:23:13 PM
Go over to 68forums and read up on it there. A lot of the data is old and outdated.
futurerancher  [Member]
4/13/2010 10:11:20 PM
Decided to go with the Grendel as it will be a stand alone hunting rifle with no tacti-cool parts. I really appreciate all the information.
jwb47  [Member]
4/13/2010 10:17:21 PM
Originally Posted By MALT0SE:
What about the .450 bushmaster? I will soon have a lower that ill be dedicating to a non 5.56 build. This will be my deer/hog/all around game gun and I most likely will not be taking any shots longer then 2-300 yards


so how does this tie in with a 6.8 or 6.5 discussion?

pavlovwolf  [Team Member]
4/13/2010 11:51:26 PM
Look at a 20" upper, or a complete rifle from AR Performance. 3300fps from a 85-90 bullet is pretty impressive. The 95gr ttsx has been available to a few for initial trial already, and will be available to the general public really soon, if not already.
Doctorxring  [Member]
4/13/2010 11:52:39 PM
.

Yes, that is the edge of the (ethical) envelope for both the 6.5 Grendel and the 6.8 SPC with finely
tuned loads and premium bullets. My choice would be the 6.8 SPC with a tuned load with
the 95 grain Barnes TTSX. This bullet was designed specifically for the 6.8 SPC ballistic
window. This cannot be said for ANY bullet for the 6.5 Grendel. There is much more
to killing power than BC, downrange energy, paper figures, etc, ad nauseam, ad infinitum.
What a bullet does when it contacts the game is a primary consideration.

Your wife is a hell of a shot if she takes pokes at game under hunting conditions at 300 yards.


QUOTE ––
"I need this rifle to be a solid 300 yard perfomer with the ability to take a follow up shot out to 400+ yards"




.
Forest  [Moderator]
4/14/2010 12:08:13 AM
Why are you selecting 20" barrels?
steve4102  [Member]
4/14/2010 8:22:41 AM
Originally Posted By futurerancher:
Decided to go with the Grendel as it will be a stand alone hunting rifle with no tacti-cool parts. I really appreciate all the information.


If you are not a handloader you may want to re-think this. 6.8 ammo is available at most places online while 6.5 Grendel ammo is almost non-existent. If you are set on the 6.5, check out the .264 LBC barrel. It's the 6.5 Grendel with a new and improved throat design, no more stuck bullets and unwanted high pressure.
http://www.lesbaer.com/264LBCAR.html

Cold  [Moderator]
4/14/2010 11:14:17 AM
Either 6.8 or 6.5 will work well for your hunting purposes.

See which one suits your fancy and budget and go with it, Im sure you will be happy.
tammons  [Member]
4/14/2010 12:27:37 PM
For hunting I don't think it matters so much within 200 yards.

Personally I prefer the 6.8 SPC to the grendel.

A 6.8 16" lightwieght barrel on a cav lower would be my preference for a 6.8 spc.
Weighs about 6# and a perfect carry rifle. Very light and handy.

The 6.5G benefits from a longer barrel, like 24" Its a better sit and wait rifle.
jasonusvi  [Member]
4/14/2010 1:52:16 PM
Which would be better out of an 18" barrel at 500-1000 yards?
Forest  [Moderator]
4/14/2010 2:01:41 PM
Originally Posted By jasonusvi:
Which would be better out of an 18" barrel at 500-1000 yards?


To a 1000y the 6.5 is the better choice with the it's higher BC bullets. But you aren't going to be hunting with either caliber at those ranges (unless it's prairie dogs).
QuicksilverJPR  [Team Member]
4/14/2010 2:32:45 PM
Originally Posted By jasonusvi:
Which would be better out of an 18" barrel at 500-1000 yards?


Better for what purpose? You're not going to have that much "E" at those distances in either caliber...but for killing dots/paper both would work.
jasonusvi  [Member]
4/14/2010 3:09:19 PM
Originally Posted By QuicksilverJPR:
Originally Posted By jasonusvi:
Which would be better out of an 18" barrel at 500-1000 yards?


Better for what purpose? You're not going to have that much "E" at those distances in either caliber...but for killing dots/paper both would work.


Paper / Zombies ... I would guess 6.5 must have the edge as the other poster suggested given higher BC. Thinking about getting an 18" for my LMT MRP... LMT currently only offer 6.8spc but thinking about getting a custom 6.5. Also like the idea that you can form 6.5 cases from 7.62x39.
Forest  [Moderator]
4/14/2010 3:27:50 PM
An 18" 6.8 CAN do 1000 yards, but you'll be buying those custom bullets from South Africa and load them yourself if you want to do it at sea level. Again the 6.5 has the better bullets for 1000y shooting.

But I dig 6.8s shooting 130s from an 18" barrel .

hi-tech-rancher  [Team Member]
4/14/2010 5:20:55 PM
Originally Posted By Forest:
Originally Posted By jasonusvi:
Which would be better out of an 18" barrel at 500-1000 yards?


To a 1000y the 6.5 is the better choice with the it's higher BC bullets. But you aren't going to be hunting with either caliber at those ranges (unless it's prairie dogs).


I took my 6.8 on a prairie dog hunt last year, shot the 90 grain Speer TNT's and was hitting them at ranges up to 400 yards, Longest confirmed kill was 404 yards....splat. Better yet, the 6.8 had a lot less wind drift than the little 55 grain VMax's we shoot in .223. I have also posted a report a year ago, after hitting an IPSC target at 500 yards, 5 out of 9 shots, with an unmagnified eotech, and that was out of a superlight weight (pencil profile) Ko-tonics chromed barrel..... same bullet, 90 grain TNT.

Look on the face of my friend, shooting his SASS, with ballistic calculator, rangefinder and kestrel, when I walked over, sat at the other bench, chuckled and bootlegged the holdover & drift......pop..............................TINK

ReflectionsBurn  [Team Member]
4/14/2010 9:27:13 PM
i have a killer report that a buddy emailed me in regards comparing the calibers it was very well done, using the human gel things to show damage...feel free to pm or email me address and i can email it to anyone wanting it, its in a pdf file
ReflectionsBurn  [Team Member]
4/14/2010 9:43:13 PM
just emailed it to you jason
tirod  [Member]
4/15/2010 9:32:54 AM
I'm not known as a 6.5 fan, but if I was consistently hunting at 400 yards - like antelope - the higher BC of the 6.5 would be a serious factor.

Then I would have to balance where to get ammo, as it definitely qualifies as a wildcat. As suggested, many 6.5 shooters go so far as to alter AK cases, and it seems to be in response to the availability, not the cost. Fun stuff for a hobby, maybe some day I can afford all the reloading gear, put up a bench, buy a powder locker, have a dedicated area where kids won't mess with things, just like my garage. Looking forward to that.

Les Baer did order a lot of unprimed cases to pump the pipeline, .264LBC will be around for awhile once in distribuition.

6.8 is the answer for the other shooters considering the choice. High BC bullets are nice, but shooting under 300m, which most hunters do, the BC offers nothing extra - it hasn't gone far enough to show it's power retention. Since the 6.8 is optimized for a shorter barrel, the combination leads to having a light weight powerful AR, easy to handle, with a low power optic. For the 6.5, a longer barrel to get the accuracy and the higher powered scope just add to expense and bulkiness. Antelope rifles aren't carbines, it's as much a matter of application as caliber.

Choosing for the 90% of hunting rather than the limited 10% of "maybe" led me to the 6.8.
QuicksilverJPR  [Team Member]
4/15/2010 10:26:43 AM
Originally Posted By tirod:
I'm not known as a 6.5 fan, but if I was consistently hunting at 400 yards - like antelope - the higher BC of the 6.5 would be a serious factor.

Then I would have to balance where to get ammo, as it definitely qualifies as a wildcat. As suggested, many 6.5 shooters go so far as to alter AK cases, and it seems to be in response to the availability, not the cost. Fun stuff for a hobby, maybe some day I can afford all the reloading gear, put up a bench, buy a powder locker, have a dedicated area where kids won't mess with things, just like my garage. Looking forward to that.

Les Baer did order a lot of unprimed cases to pump the pipeline, .264LBC will be around for awhile once in distribuition.

6.8 is the answer for the other shooters considering the choice. High BC bullets are nice, but shooting under 300m, which most hunters do, the BC offers nothing extra - it hasn't gone far enough to show it's power retention. Since the 6.8 is optimized for a shorter barrel, the combination leads to having a light weight powerful AR, easy to handle, with a low power optic. For the 6.5, a longer barrel to get the accuracy and the higher powered scope just add to expense and bulkiness. Antelope rifles aren't carbines, it's as much a matter of application as caliber.

Choosing for the 90% of hunting rather than the limited 10% of "maybe" led me to the 6.8.


Just not enough E from either cartridge to reliably hunt at those ranges. That's why I would use .25-06 or something similar (or 243 WSSM)...

tammons  [Member]
4/15/2010 10:28:32 AM
Originally Posted By jasonusvi:
Which would be better out of an 18" barrel at 500-1000 yards?


500 NBD for target for either.
Neither for hunting past 500 yards.
300-400 yards should be about the max for hunting with either IMO

Step up to a 243wssm, 25wssm, 6.5 wssm for 1000 yards.
Better yet a 308



Dogue  [Team Member]
4/15/2010 12:59:49 PM
Originally Posted By tirod:
6.8 is the answer for the other shooters considering the choice. High BC bullets are nice, but shooting under 300m, which most hunters do, the BC offers nothing extra - it hasn't gone far enough to show it's power retention. Since the 6.8 is optimized for a shorter barrel, the combination leads to having a light weight powerful AR, easy to handle, with a low power optic. For the 6.5, a longer barrel to get the accuracy and the higher powered scope just add to expense and bulkiness. Antelope rifles aren't carbines, it's as much a matter of application as caliber.

Choosing for the 90% of hunting rather than the limited 10% of "maybe" led me to the 6.8.

Actually, the 6.5 round is perfect for 18" barrels with little velocity lost and accuracy isn't affected by the shorter barrel. For a bench rest guy the 24" is fine but in the real world the 16-20" Grendel is more than adequate. Both guns will be similar at short-mid range but the grendel's higher BC, and usually heavier bullets give it the long range advantage. Even at 200-500 yards the higher BC will help with drift - it's not just for holding velocity.

Personally, I wouldn't take the shot at 1k (or even 500) unless my life depended on it.

coldair  [Team Member]
4/15/2010 1:09:15 PM
I can shoot .5" groups all day long with my 18" 6.8 shooting 110 grain prohunters kicking between 2890 and 2915
NE223  [Team Member]
4/22/2010 9:24:00 PM
Beyond 400 yards on mule deer, I'm going to more rifle than either the 6.8 or the 6.5G.
Grendelizor  [Member]
4/23/2010 1:38:32 PM
Originally Posted By NE223:Beyond 400 yards on mule deer, I'm going to more rifle than either the 6.8 or the 6.5G.


Is your concern stopping power or external ballistics?

Mark LaRue's bull elk at 405 yards wasn't too happy about the 6.5 Grendel's stopping power with a Barnes 120 TSX from a 20" barrel.

John

| 6.5 Grendel + AR15 = The Ultimate Hunting Machine |

www.65grendel.com

QuicksilverJPR  [Team Member]
4/23/2010 2:42:02 PM
Originally Posted By Grendelizor:
Originally Posted By NE223:Beyond 400 yards on mule deer, I'm going to more rifle than either the 6.8 or the 6.5G.


Is your concern stopping power or external ballistics?

Mark LaRue's bull elk at 405 yards wasn't too happy about the 6.5 Grendel's stopping power with a Barnes 120 TSX from a 20" barrel.

John

| 6.5 Grendel + AR15 = The Ultimate Hunting Machine |

www.65grendel.com



And again I say it's near the extreme end of what is usually considered the ethical energy limit of those midpower cartridges. Personally, I know I could take and make similar shots myself (and I know Mark LaRue shoots a good bit as well), but just because you can do a thing, doesn't mean it should be the "standard bearer" for the entire cartridge and platform...

Now if I see something worth shooting at ranges like that and all I have with me is my 6.8 or 6.5, well, yeah, I'm going to take the shot


ETA- Barnes bullets do give an advantage, IMHO...especially on game like that.