Comparing factory 6.5 and other calibers

[Kilco]

Lightstrider, I had many of the same questions as you initially, and didn't want to invest so much in a cartridge I would later regret. It was LRRPF52s "matter of fact" info and factual information that pushed me over the edge to invest in the 6.5 Grendel.

Fast foward two years, and my AR15 chambered in the Grendel is hands down, without a shadow of doubt my favorite rifle I own. It does everything I want and then some with a 16" barrel. I can hunt anything here in Maine with it, long range work is a blast, and it's phenomenal for my wife and kids to shoot. Stupid reliable, ammo and handloading supplies are plentiful and it's growing all the time.

I used to shoot a 18" DMR with match style 5.56 ammo (69-77gr) regularly. There is absolutely NOTHING that the match 5.56 can do that the Grendel won't do either better, or MUCH better. Wind deflection is very imporant to me. The Grendel slices through wind as if the bullets were made of teflon. It's impressive to behold first hand.

Buy with confidence!

Let alone the fact that this cartridge has two amazing handbooks breaking down every ammo and how it performs in the Grendel with enormous detail. Great bathroom reads!

[Lightstrider]

Sounds like the place that made all these comments is filled with people who are really uninformed.

that's the AKfiles I guess

[StoneHendge]

"Give the suckers a break and let them keep thinking they have a .308 in an AR-15"

This guy cracks me up the most. I know I'm not shooting my .308 AR-10 every time I pull the trigger on my Grendel and I feel less recoil, hear less of a bang and am able to spot my own hits. I know I'm not shooting my .308 AR-10 when I can put twice as many rounds downrange in a session. I know I haven't been shooting my .308 AR 10 when I pick it up to go home, and then when I get home, my shoulder isn't sore and my ears aren't ringing.

These are the sorts of guys who you run into at the range who will trash your Grendel and then develop some sort of unforeseen problem with their rifle, ammo or scope once they can see what a Grendel can do in the right hands.

Also had one guy a month or so ago who was with some buddies and couldn't stop spouting off about how great and accurate his AKs were. He started talking to me and usual BS started coming out so I asked "would you like to try it? I've been shooting at the 10" plate at 450 up on the hill - I'm holding just under 3 mils high and left edge." His response was "where's the target?" (we only have one 450!)

[Lightstrider]

Here's a rebuttal for the Wolf 6.5 vs 7.62x39 equivalent, all in good fun.

The wolf 6.5 Grendel with a muzzle velocity of 2600fps from a 24" barrel only comes out to about 2350fps from a 16" which is the same as GT 7.62.

Range reports from a match grade 24" 6.5 Grendel rifle show about 3 MOA from the Wolf ammo. I've gotten better groupings with 7.62 GT from a plain AKM.

Ballistic coefficients of a 100 grain FMJBT .264" bullet is about .35, and ballistic coefficients of GT 7.62 123 grain FMJBT is about .3 (about the difference between 55 and 62 grain .224").

With these numbers we can calculate the ballistics of these and it will show that the Golden Tiger 7.62 ammunition actually has MORE energy than 6.5 grendel out to 500 yards but at this distance the point of impact is only about 9 inches lower. Muzzle energy is about 300ft/lbs greater for the GT.

So yeah, the Wolf 6.5 Grendel ammunition is as I've described it. It's shit. And the cost per round climbs incredibly once you get into better ammo (like 123gr a-max match loads).

[Kilco]

Show me a guy who claims his 7.62x39 (ak,ar,bolt, doesnt matter) who claims it has more stuff than a grendel at any distance, and I'll show you a guy who has never taken his 7.62x39 past 200 yards.

[LRRPF52]

16 inch barrel AR15, Wolf 100gr FMJ
Average of 10 shots
2496 FPS
Extreme Spread
35 FPS
Standard Deviation
11 FPS

If someone is telling you that Wolf 100gr FMJ is only clocking 2350fps from a 16" barrel, they are uninformed.
If there is one cartridge that 6.5 Grendel slays without even trying, it is 7.62x39, and is a good comparison to show why BC matters so much.

Put a 123gr x39 next to 6.5mm, same barrel length. One of them has 3-4x the effective range of the other.

[Lightstrider]

There seems to be a rift in the gun community with the 6.5 Grendel lol, I'm just on my own personal journey trying to get multiple perspectives because not only is this all interesting and fun, I'm also considering investing into this and utilizing it everyday in my regular life, but sharing different views I've gathered from others has me suspected of shilling for 6.5 Grendel.

Ahh the thread unfolds. Lightstrider creates a thread asking AK files for our opinion on getting a grendel upper. When our comments weren't to his liking he forwards them to LRPF52 who's not a files member IIRC. So lightstrider if you have someone like LRPF52 who's experienced with the grendel on speed dial then why come to AK files for advice on an upper? If you didn't want to hear our opinion then why forward our comments to LRPF52? Or are you not needing our thoughts on an upper and maybe this thread was just created to keep the grendel in the public ear. Slightly deceptive of you and bordering on shilling IMO to say the least. This is one of many grendel threads I've come across which are seemingly created just to give the grendel some publicly.

LRRP one guy wants to know if you think that the grendel wolf ammo is not accurate or consistent enough to range out any further than 5.56 on a man sized target. Then here is a rebuttal for one of your rebuttals:

Originally Posted by LPRF52
6.5 Grendel has 77% of the energy of the CM at 1000yds. They need to show their work if they are going to make these types of unsupported claims.

Show my work, sure here it is. 77% of the energy huh, that would be 547 ft/lbs according to my ballistic calculator you'd have to launch the Grendel at 2, 905 fps to make it happen an interesting claim indeed being as that Hornady claims 2, 350 fps from a 16".

6.5 CM actually makes 104% more energy in this comparison which to be fair is an 18" creed vs a 16" grendel. So my previous statement of 90% more energy isn't ridiculous when equal length barrels are used.

At 1000 yards the Creed has
-104% more energy
-43" less wind drift
-13 ft less drop

No comparison really

6.5 Creed 18" barrel


Grendel 16" barrel

Another one is interested about "The Grendel also hits harder within closer ranges than the 7.62x39."

Would whoever actually posted this mind explaining how that could be? At closer ranges the numbers are pretty close to identical until you get to a distance where retained momentum actually makes a difference.

[maxxmojo]

While I get your quest for knowledge, it's kind of in bad form to be slinging drama from one forum to another.

[Lightstrider]

Yeah I get that and it's all he said she said this that when it seems some people don't have experience with the 6.5G and give it a bad rep.

[rabiddawg]

A lot of people hate to admit they are wrong, made a mistake and regret a decision. I have a bil that my family and friends joke about "I don't know" not being in his vocabulary.

After doing my research, I chose the Grendel. I do Not regret it one bit and have 5 of them now to prove it.

It's the best feeling in the world when someone comes up to you at the range and asks what are you shooting? You show them and they just can't believe it. I've had one guy get behind my rifle after asking that question. He pestered me for 2 weeks trying to buy that gun.

[pajasonc]

some 7.62x39 will leave the barrel at around 2400 fps. The prvi stuff typically clocks in the low 2400's out of a 16" and in the mid to upper 2400's out of a 20". There was a guy on the AR15 forums who was running 125 nosler BT(308 bullet) at 2450 thats a pretty good load in the x39(if it shoots it well most AK's won't most AR's will), Still they are the same weight bullet going the same speeds at the muzzle. Inside 100 I really doubt there is much difference between the two. Outside of that the grendel pull's ahead and once your past 300 there really is no comparison.

[Lightstrider]

Idk for cheap Wolf ammo that was designed like 7N6 it looks like a pretty nasty bullet even if you are only getting 3MOA from it....




Exit is pretty large, .75" to 1" hole.


100 grain Wolf FMJ steel case fired from a 14.5 inch AA 6.5mm Grendel carbine at 10 yards.
Nose broke off in the block, the rest of the projectile exited the 16 inch block.

[LRRPF52]

1st overlook, but not a huge one: A lot of people look at the Hornady data for 16" on their site, which is really an AA 14.5" upper pinned with a muzzle device bringing it to just over 16" for legality. Hornady used that upper for their 8th Edition load data as well.

I called up Hornady tech support and asked them to verify this, and they put their hands on it, and said, "Yeah, that is the 16" upper we used, which is actually a 14.5" barrel pinned."

2nd mistake: Different barrel lengths. 2350fps is a slow 14.5" Grendel, normal for a 12.5" Grendel with 123gr Scenar from AA. The Saber CL 14.5" barrels would do 2420fps average.

Contrast
For my comparison, I used a 24" Grendel vs. 24" 6.5 Creedmoor (level playing field, logical concepts of fairness and accuracy, as well as relevancy) pushing a 123gr Scenar and 140gr AMAX in both, so 2 actual comparisons. I've done this exercise several times over the years when I first looked at my .260 Rem data next to 6.5 Grendel, and was surprised at how close they actually are.

3rd and 4th Problems
In the comparison listed above, they used a 123gr SST with the wrong BC with the G1 modeling, (it's actually much lower at .462 G1) at 12.5" to 14.5" barrel velocity, against an 18" 6.5 CM pushing a 147gr ELD-M using the G7 modeling for Mach 2.5 speed range, which an 18" CM will send a bullet through for a few yards before going into a lower G7 BC values. The only thing they got right was the muzzle velocity for an 18" 6.5 CM at 2550fps.

I used the exact same bullets for both Grendel and CM, 123gr Scenar and 140gr AMAX, so 4 total samples all from the same barrel lengths, not a .462 G1 123gr against a .662 G1 147gr ELD-M. If you really wanted to cherry-pick like that, the 147gr ELD-M would be the bullet to use for the Creedmoor though. It's a selective form of making a technical argument that most layman will not notice.

Here's a 24" 6.5 CM or .260 Rem with 129gr ABLR or 130gr Berger at 2820fps, using Litz G7 modeling for 1000yds at sea level barometric pressure:
1000yd 1442fps 595ft-lbs 2.1 mils drift

24" 6.5 Grendel 129gr ABLR, 2520fps
1000yd 1230fps 433ft-lbs 2.5 mils drift

433/595 = 73%
With the 123gr SMK at 2920/2620fps, you get 73% again.
With the 140gr AMAX at 2740/2440fps, you get 73% again.

With CFE or LVR in the Grendel, the 140gr AMAX goes faster than I thought it would, and can get you to 2500fps, which is 78% of the energy of the CM.

The 24" 6.5 Grendel with a 129gr ABLR has 73% of the energy of a 24" 6.5CM shooting the same bullet, when both impacts are measured at 1000yds, using the theoretical G7 drag model, the one that is appropriate for 600yds on out.

I have several 6.5 Grendels (22"AR15, 22" Howa bolt gun, 18", 17.6" Lilja, 16"AA), .260 Remington (my 2nd-22"), and 6.5 Creedmoor (24") myself, so I've become intimately familiar with the capabilities and limitations of them all over the years. Just added the 22" Grendel bolt Howa Mini and Howa 24" chassis 6.5 CM rifles, which I'm reviewing. I've been spotting for and shooting all of these cartridges, as well as the 6.5x47 Lapua, 6mm Dasher, 6mm BR, 6.5x55, and pretty much everyone I know has several samples of several of the above. I see them all come through courses and LR events every year, throughout the year.

What I have found with the 6.5-08 cartridges compared to the 6.5 Grendel, using the exact same bullet, is that the larger class cases will hit the Grendel's muzzle velocity anywhere from 175-225yds. Using the same barrel length 6.5 Grendel effectively cuts off 175-225yds of usable range from the 6.5CM or .260 Rem with AR15s, and 100yds from bolt guns.

Example: 6.5 CM or .260 Rem pushing a 129gr ABLR or 130gr Berger AR at 2820fps from a 22" barrel will hit a 22" Grendel's mv like this:

Bolt gun Grendel mv is reached at 100yds 2660fps

CM/.260 reaches AR15 mv at:
175yds 2544fps
200yds 2505fps
225yds 2468fps

From my 18" Grendels and others I have built and chrono'd, mv with a 129gr ABLR and CFE at 50ksi is just over 2400fps. So I had a serious look inside myself and the way I use rifles, and asked if I really needed to lug the heavier guns around, when that type of performance even from a shorter Grendel was available. For me, that answer was that for most things, no. If I was primarily shooting 700-1400yds, then I'm reaching for the 6.5 CM or .260 Rem. My wind drift is simply less, as is drop.

That ballistics comparison done on AKfiles is a good example of how the data can be cherry-picked and skewed. I want to say it was the simple mistake of someone just learning the language of external ballistics, but the fact that different drag models have to be manually selected leads me to believe that it was intentional.

[Kilco]

Great read LRRPF52!! Solid info for sure. My experience is very similar coming from years of varmint bolt guns then transfering my attention to the Grendel. Love my bolt guns, I just rarely find myself reaching for them in the safe anymore.

[Lightstrider]

Yeah good stuff, thanks. Obviously 6.5C is going to be the better choice for those much longer ranges if you really need the performance at those ranges, however as you said for yourself that you don't really need to lug around the larger frame rifle when 6.5G is lacking merely 30% or so of what you get out of 6.5C. This guys reasoning for shrugging off the 6.5G is that he'd just rather use 5.56 and then 6.5C if it gets to longer ranges, that's all fine and dandy it's personal choice but obviously 6.5G does has a lot more potential than 5.56 from the same system. Otherwise the reasons some are also shrugging off 6.5G is that supposedly it's expensive or unreliable which they must only be aware of the issues surrounding the bolts and magazines when it was first coming out as the issues are slim to none.

I already have a 5.56 and I have two 7.62x51s, for me I want the lighter platform with more of a punch while also maintaining accuracy which my 7.62x39 AKM doesn't necessarily provide. Then I'm seeing 6-7lb rifles here with 6.5G getting subMOA groups plus the extra punch compared to the 5.56 and extra accuracy compared to the 7.62x39. There's nothing wrong with the 5.56 either, there's plenty of choices to be effective at whatever but just like the personal choice made to just use a heavier 6.5C it's a personal choice to just want a little bit more out of the AR15 rifle.