Is the 6.5 Grendel a True Long Range Hunting Cartridge?

[J E Custom]

What brand of 6.8 ammo gives you 400-500 more fps? Just curious since both cases hold the same amount of powder.

Alexander arms (The company that designed the Grendel) best load produces 2376 ft/sec for 1505 ft/lbs of energy.

Remington (The designer of the 6.8 SPC) has several loads that produce, 2800 ft/sec for 2002 ft/lbs of energy. and there FMJs produce 2625 ft/sec for 1759 ft/lbs of energy.

Also the 6.8 SPC will hold more powder than the Grendel and the 6.8 can use the 5.56 mags (They wont hold as many rounds but they will work well). The same powder in the Grendel is compressed @25.4 grains and in the 6.8 SPC it is compressed at 28.2 grains for a 2.8 gain in volume for a 10% gain
in case capacity. 2.8 doesn't sound like much gain but 10% is enough to have a velocity increase of 424 ft sec.

Note: this is not the only reason I went with the 6.8, but it contributed to the decision.

J E CUSTOM

 

[olsingleshot]

Well you are partially correct. The Grendel hold 36.2 water and the 6.8 holds 36.8 water and can use 5.56 mags. However if you judge the cartridges with the same or close bullet weights like the SST, the velocity out of 16" barrels favors the 6.8 by 100fps but with a lighter bullet. You can verify this on the Hornady site, 400-500fps is a tremendous exaggeration. I think both are far closer ballistically under 400 yards than you may think. At long distance the 25% better BC in the 6.5 SST kick in. Admittedly I do not have extensive reloading experience with either round but I do have the resources to get a good idea of what they can do. The 6.8 is a tremendous round for hogs. Thank you for your imput.

Case capacities verified on ammoguide.com

 

[toddc]

I can buy the 400 FPS claim with the same bullet weights. A 277 with the same weight slug will have a lot more bore area for gas to push on and quite a bit less bearing surface than a 6.5.
I don't see the Grendel or the SPC as any kind of LR round anyway especially in gas guns with the 18" tubes that many come with. The Grendel may have a THEORETICAL advantage past 400 but NEITHER round is a LEGIT 400 YD deer round anyway except under extreme circumstances.
Yeah I know Jethro's brothers bruncle killed a 32 point at 1200 yds with one, but there are a lot of massively better rounds out there for 400+ yd work, some of them even come in the AR platform.

 

[J E Custom]

Well you are partially correct. The Grendel hold 36.2 water and the 6.8 holds 36.8 water and can use 5.56 mags. However if you judge the cartridges with the same or close bullet weights like the SST, the velocity out of 16" barrels favors the 6.8 by 100fps but with a lighter bullet. You can verify this on the Hornady site, 400-500fps is a tremendous exaggeration. I think both are far closer ballistically under 400 yards than you may think. At long distance the 25% better BC in the 6.5 SST kick in. Admittedly I do not have extensive reloading experience with either round but I do have the resources to get a good idea of what they can do. The 6.8 is a tremendous round for hogs. Thank you for your imput.

Case capacities verified on ammoguide.com

I agree that they are close, and I wanted to build ether on an AR platform for hogs. I built a Grendel
for a good friend and was fortunate enough to brake it in for him and also chronograph the factory loads for it, The results were very close to Alexander arms specs in his 20" barrel. I had my doubts
about the 6.8 doing what Remington advertised and found that In my 6.8 AR the velocities were spot on as advertised (Within + or - 10 ft/sec) The only thing I found with re loads is that I could not reach the same velocities. I can load within 50 ft/sec of the factory loads. so Remington has a proprietary loading like so many other factory loadings that we cant achieve.

The best velocity so far with the 115 grain reloads with SMK bullets has been 2761 ft/sec (One of the bullets that Remington uses) I also built a bolt action in the 6.8 with a custom barrel and the results were very close with my re loads and the velocity exceeded the factory ammo velocities by a small amount (It is not unusual for premium custom barrels to exceed listed velocities by a small amount) using there ammo.

I also tried other brands of 6.8 Ammo and found them to be only 100+ ft/sec faster than the Grendel so your comparison is very close with the Hornady, Federal and SSA. I have much more powerful cartridges in .277 diameter but they require a AR10 platform and I wanted the most bang for my buck in a AR 15. All test were conducted over a Ohler 35p with like rifles and factory ammo
that advertised the best performance. so they are not out of a book or from internet claims and with proven velocities over 400 ft/sec, the range of 400 to 500 is not exaggeration with bullet weights within 5 grains.

I take nothing away from the Grendel, I just chose the 6.8 SPC and I don't consider ether one a long range cartridge. My friend loves his Grendel and wants me to build him a bolt action in the 6.5 Grendel.

J E CUSTOM

 

[J E Custom]

I can buy the 400 FPS claim with the same bullet weights. A 277 with the same weight slug will have a lot more bore area for gas to push on and quite a bit less bearing surface than a 6.5.
I don't see the Grendel or the SPC as any kind of LR round anyway especially in gas guns with the 18" tubes that many come with. The Grendel may have a THEORETICAL advantage past 400 but NEITHER round is a LEGIT 400 YD deer round anyway except under extreme circumstances.
Yeah I know Jethro's brothers bruncle killed a 32 point at 1200 yds with one, but there are a lot of massively better rounds out there for 400+ yd work, some of them even come in the AR platform.

Just for kicks I ran the ballistic numbers of the two best loads used at 600 yards and the results
are as follows. (Interesting)

6.5 Grendel =
120 gr SMK with a BC of .421 @ 2376 (Advertised and chronographed)
600 yard ballistics =
Drop @ 600 yards= 165.4 inches.
Velocity @ 600 yards= 1374 ft/sec.
Energy @ 600 yards= 503 ft/lbs energy

6.8 SPC =
115 gr SMK with a BC of .324 @ 2800 (Advertised and chronographed)
600 yard Ballistics =
Drop @ 600 yards= 132.4 inches. (33 inches flatter than the Grendel)
Velocity @ 600 yards= 1400 ft/sec. (26 ft/sec faster than the Grendel)
Energy @ 600 yards= 501 ft/lbs (2 Ft/lbs less than the Grendel)

So at 600 yards they are almost exactly the same in performance. Nether one is suitable for big game even 600 yards with only 500 ft/lbs of energy available and velocities below the recommended ft/sec of most bullets. With good BCs bullet velocity is important to get down range performance and in this case the velocity increase made up for the higher BC.

Interesting outcome don't you think?

J E CUSTOM

 

[olsingleshot]

Advertised by which company? Try running the 120 and 123 SST factory ammunition out of a 16" barrel. Remington says that the 115gr SMK out of 6.8(unknown barrel length) goes 2625 fps. and I am pretty sure you said you could not match their velocity. I am not aware of anyone one making factory ammunition for the Grendel with the SMK but could be. You have the Grendel starting out at a 400fps disadvantage where 100fps would be closer to real. I am just looking for an apples to apples comparison with factory ammo.

 

[J E Custom]

Advertised by which company? Try running the 120 and 123 SST factory ammunition out of a 16" barrel. Remington says that the 115gr SMK out of 6.8(unknown barrel length) goes 2625 fps. and I am pretty sure you said you could not match their velocity. I am not aware of anyone one making factory ammunition for the Grendel with the SMK but could be. You have the Grendel starting out at a 400fps disadvantage where 100fps would be closer to real. I am just looking for an apples to apples comparison with factory ammo.

This is not an argument, it is a discussion and all I did was test the ammo in 20" barreled rifles that was advertised by the Ammo Makers. and in order to compare apples to apples I used the Match king because they made the same bullets in the same weights that the factories used to make an accurate comparison. actually giving the Grendel a BC advantage.

Here is a link to the Remington ammo that I tested and it advertises 2800 ft/sec. the factory velocities were correct in both rifles and the Grendel with a 20 '' barrel averaged 20 to 30 ft/sec
over the listed velocity with an 18' Barrel.

Remington Premier Match Ammo 6.8mm Remington SPC 115 Grain Sierra

Actually This post has helped me in two ways, I now know not to use either of my 6.8s beyond 400 yards and I am happier with my choice than ever.

The information proved that the 6.5 Grendel was not a long range rifle on big game and in spite of the comparison to the 6.8 SPC which was not intended, it happened and if someone was insulted that was not the intent. If they don't believe the numbers they have to live with it. if they want to have more power/velocity they should buy another rifle/cartridge even though there is nothing wrong with the Grendel.

I could compare reload data but as we all know the results would vary because of many variables
and would not be a fair comparison. I know I could over load my bolt gun and boost the velocities
even more, but that would not be a fair comparison just like if a Grendel was over loaded I am confident that it could exceed the 6.8 velocities.

Use this information how ever you want.

J E CUSTOM

 

[olsingleshot]

I agree it is a discussion. I just thought a fair comparison would have been factory Hornady ammo since that is the only factory made ammo for both and only 3grs apart with the same design bullet. When I have a chance I will run it. True enough I do not know the 6.8 as well as you and my experience with the 6.5 Grendel is not in an AR15. I do know all the hog hunters I know that shoot the 6.8, shoot factory 120SST. I have learned a few things also. As a writer I try to keep an open mind.

 

[J E Custom]

I agree it is a discussion. I just thought a fair comparison would have been factory Hornady ammo since that is the only factory made ammo for both and only 3grs apart with the same design bullet. When I have a chance I will run it. True enough I do not know the 6.8 as well as you and my experience with the 6.5 Grendel is not in an AR15. I do know all the hog hunters I know that shoot the 6.8, shoot factory 120SST. I have learned a few things also. As a writer I try to keep an open mind.

Thanks.

With all the internet Hype and claims, I don't believe most of the claims and test as much as I can
to prove (To myself) before I comment on anything. Manufactures seem to elaborate on there products performance and use only best case conditions

The reason I use the Remington ammo Was because it was advertised as the fastest and they designed the 6.8 SPC. and I used 120 grain Alexander arms ammo for the same reason.(They advertised it for a 18" barrel) so I expected it to be a little faster in the 20" barrel and gave a real world comparison because all three rifles had a 20" barrels.

Hornady tested there ammo in a 24" test gun and used a 123 grain bullets and clamed more velocity than the designers of the Grendel. my friend was unable to match there velocity in his 20" AR so it was not considered for a comparison. also it did not compare to the Remington. I will try the 120 grain Hornady in my bolt action rifle and see what the velocity is. I did try the 115 FMJ rem
ammo and it was an average of 100 ft/sec slower than the SMK ammo.

J E CUSTOM

 

[olsingleshot]

I understand your feelings. Hornady does give velocities in a 16" as well as a longer barrel. Just curious what barrel length and bullet do you use for hogs? It appears to me the Grendel is like the .260, best velocities would be found in a longer OAL round since the bullet sits so far into the case in order to fit an AR15 magazine.

 

[Niles Coyote]

I love this little cartridge. I started playing around with it last year.

I built mine on a Mega Arms receiver set using a 1:8 twist 18" JP Enterprise lightweight barrel, JP Enterprise full mass carrier, captured recoil spring and brake, Geissele SD-E two stage trigger and a magpul CTR stock. Weights around 8.5 to just uner 10 pounds depending on the scope I am using (NF 4-16F1 or Vortex 2.5-10x32)

On coyote patrol in SE Montana a couple months back.

Why do I like it so?
From day one it was a good shooter. While doing load work up every group in my modified version of an OCW was printing between 1.25 and .5 moa. While there is a higher velocity node available I settled on 26.8 grains of AR-Comp with both 123 Lapua scenars and Hornady A-Max seating Lapua's at 2.24" and Amax at 2.253". After putting a little over 150 rounds down the barrel trying different bullet I cleaned the bore thoroughly. Next time at the range I set up my magnetospeed for the first 6 fired in a clean cold barrel. This was the result.

The first two shots were the only ones in the 2430's

The next trip at the range I shot a cold bore/cold shooter shot at 300 yards

Then preceded to drop the next three on the 600y plate.

Every time I've taken this gun to the range I have repeated the cold bore/shooter shot with the same result. I have added a 100 yards each time until I got to 500 and put 500 as my personal cap because that's really as far as I care to go when hunting coyote and deer with this cartridge. Its always been a consistent performer.

My best 1000 yard group to date

and 123 amax at 100y

Factory Hornady 123 A-max shoots at a velocity right around 2570 in this barrel and I have run reloads up to just over 2600 but none have given me the performance 26.8 grains of AR-Comp has.

Short on time for my last chance at shooting the Smack the Smiley's postal match (had to pack for a montana mule deer trip)
Smack the Smiley --- Home of the Tactical Shooter's Local Rifle Match
I grabbed the Grendel for a quick trip to my 100 yard range.

Had my reticle not covered the 30 point circle I'd have targeted that for my confidence shot rather than the 25 point circle. This thing is every bit as accurate as my best custom when you have to fire on demand and accept what you get.

I'll close with, I love the cartridge so much I am expecting delivery of a new 20" H-bar Bartlien barrel any day now.

 

[olsingleshot]

Thank you for taking the time to share. That is a fine rifle that you have set up. The accuracy does not surprise me at all. As far a distance shooting: I think 300-400 should be max for medium game animals such as deer and antelope. As far as varmints, I think you could go way past that. Have fun!

 

[yorke-1]

Great write up. I came to pretty much the same conclusion as you did about the little Grendel. It's not a very potent round, but it's a great 400 yard and under deer round. I had a CZ 527 converted to the Grendel a while back and it's a great little combo that I used on 2 deer last year.




I've got a 19" barrel on the little CZ and I get 2430 fps with the 130 Accubond or 2465 fps with a 130gr Berger. As long as you have realistic expectations, the Grendel is a great round.

On a side note, CZ is going to make the 6.5 Grendel a factory chambering in the CZ 527 very soon!

 

[olsingleshot]

That is a nice looking rifle. What brand of barrel did you choose? Also, using 130gr bullets what is your OAL? Have you tried lighter bullets?