Can ya'll provide me thoughts on 6.5 Grendel Caliber - tactical and practical?

[Varminterror]

The bolt face is too big for the AR bolt, so it breaks bolts and extractors.

This is a legitimate concern, for sure. I've not personally broken a bolt in the Grendel, nor my customers, yet. I have broken them in 5.56/223. I only use JP and Young bolts for the Grendel, for this reason. Maybe I'm a shot away from catastrophe with the Grendel, it's always hard to predict the future.

I have never struggled to get a Grendel/LBC to feed; I keep an eye on it, as I've heard the same said about 6.5 creedmoors and 243 AI in an LR-308 before I built mine, or the 243 and 25 WSSM's before I bought mine... I do the same reliability work up to all of my AR's, and I have never experienced feeding failures for these steep shoulder, low body taper rounds. As far as performance goes, it's true the 5.56/223 runs faster and flatter, and with less powder than the Grendel, I run about 15% more powder behind a 123 ELD than I do in the 73 ELD, and the Grendel drops about 5" more at 500, but they do almost even out on drop way out there. What the Grendel DOES have, however, is a much meatier impact at range, so where a 73 ELD or 77 SMK will barely rock a 66% IPSC at 800yrds, the Grendel will give a positive clang and swing to the plate. An 8" round at 800 will spin on the chain with the Grendel, but barely swing with a 5.56 - the difference is clear on game as well. Coyotes at 600yrds run away from the 5.56, the heavier Grendel pills anchor them much faster (although I do use an 18" 6.8 for most of my coyote calling work, but same-same, really).

Inside the rifle, or on the loading bench, there's a lot to complain about any of the higher-hunting-performance AR cartridges, whether it's the over-length body of the 6.8spc, the over-sized base of the Grendel, or the extreme pain in the ass found in forming 7 Valkyrie... but it sure is nice getting game on the ground more quickly in the field, without sacrificing usable range like the super-weight cartridges.

 

[SteveChuck]

Bill Alexander is such a horrible person I can't imagine anyone does business anywhere near him.

I take it that you and Bill Alexander had a falling out of some kind. Alrighty then.

 

[Llama Bob]

I take it that you and Bill Alexander had a falling out of some kind. Alrighty then.

Nah, I've just watched him screw his suppliers, customers, and investors. I hadn't been paying attention but apparently the investors finally gave him the boot this summer - he's off to "pursue other opportunities". Nice euphemism that

 

[Walkalong]

Is that a reason not to choose the caliber if you like it?

 

[Varminterror]

Is that a reason not to choose the caliber if you like it?

It definitely was at one point in time. Unless you went the Les Baer route, until a handful of years ago, you were beholden to Alexander for the Grendel. Stubborn pride and greed kept a lot of people out of the round for many years. I don't have a dog in the fight, but it was what it was, and what it was, was not good, for a long while.

 

[barnbwt]

The Grendel is the worst designed round to enter commercial production in recent memory. The performance is no better than heavy 5.56 at the same bolt thrust, and worse than the 224 Valkyrie. Fail #1. The bolt face is too big for the AR bolt, so it breaks bolts and extractors. They had to re-design the chamber, and it still sucks. Fail #2. The high-taper cartridge doesn't feed well even with special magazines. The fact is the AR has a straight magazine well. The magazine can't change that. Fail #3.

It's really a pathetically mis-designed cartridge, and Bill Alexander is exactly the kind of power tool that would create such an abomination.

Do we really need to do this again?
1) It's common load is 2X the weight of 'heavy' 5.56
2) Yeah, it runs at slightly higher bolt thrust. No, it hasn't broken bolts since poorly made 7.62x39 bolts were pressed into 'Grendel-ish' service by unscrupulous vendors
3) Explain in numbers just how different Valkyrie is from Grendel and 6.8 SPC; they all roughly overlap
4) Extractor failure was due to non-ideal claw geometry resulting from aforementioned 7.62x39 bolts being used with deep-chambered barrels dishonestly sold as 'Grendels'
5) Alexander didn't redesign the chamber, a knock off company did despite his best efforts because they didn't want to grind the correct reamer. That ill-fated venture is mostly dead & gone now that proper Grendel bolts are available. You're thinking of SPC.
6) High taper cartridge? It's blown out from 7.62x39 taper to about the same taper as 5.56. The specific mags are due to the cartridge being wider (an issue for all rounds wider than 5.56, sadly, and the primary limiting factor of the AR15 itself).
7) Some weirdly personal yet totally non-specific ad hominems against Bill Alexander

Are you sure you have experience with this cartridge?

 

[Llama Bob]

Is that a reason not to choose the caliber if you like it?

No, but his involvement does explain the rather obvious design mistakes.

 

[Llama Bob]

You know, I hadn't looked into it in a year or so, and it appears now we have incompatible Type 1, Type 2, AND SAAMI reamers plus .264 LBC for for four total chambers. My how these things proliferate! With any luck the number of badly designed chamber specifications will double every couple of years and in 2018 or 2019 we'll have eight

Of course the reason they keep multiplying is that fundamentally the cartridge is mis-designed. Too big, too high a pressure, too much bolt thrust and too fat a case head all jammed in too small a platform.

 

[HankC]

Unless you shoot long distance, 277 Wolverine worth the wait, give it couple more years.

 

[Walkalong]

Too big, too high a pressure, too much bolt thrust and too fat a case head all jammed in too small a platform.

How about explaining those shortcomings more clearly in detail for those of us who are less informed.........

 

[farmerboy78]

Well, I have ran a Lilia barreled grendel suppressed for over a year now. I haven' had one single issue with jamming or ftf or fte... the SUPPRESSOR should add to bolt thrust and still not one issue. I have ran it dirty as hell and spic n span clean... have only needed to apply oil and keep on firing! Like everything, there are haters out there for one reason or another. This is an absolutely amazing cartridge for the ar15 that's plenty for medium game hunting such a whitetail. The grendel, imho, is also a great cartridge to teach younger shooters on, due to good performance and very mild recoil.

 

[Llama Bob]

How about explaining those shortcomings more clearly in detail for those of us who are less informed.........

Well, start with the bolt. The stock AR-15/M4/M16 is already bolt thrust limited. The chamber and lockup are plenty strong, but the bolt lugs are weak and prone to shearing. That's in the .223/5.56. This is a point the military is constantly having problems with, and is the sole reason the 5.56 runs at a much lower pressure than nearly all modern bottle neck center-fires. It's also why the military has a MPI inspection requirement on the bolt - something done on almost no other firearm pressure components.

Then you go to a 7.62x39 bolt face, and you have to take a whole bunch of metal out of the bolt face to make space. Uh oh... These problems all cropped up on various 7.62x39 ARs, but that market is about 3 guns so no one cared too much.

Enter the Grendel. AA went with a deep bolt face borrowed from the Colt 7.62x39 bolt. This maximized the chance of bolt breakage but prevented extractor breakage. Other manufacturers thought this was silly (it was) and went with the aftermarket style shallow face bolt, which protected the bolt (but not near to the level of a 5.56) and sacrificed the extractor. The customers were the ultimate losers in this as literally every gun produced under either scheme was faulty and at least mildly dangerous - usually a broken bolt isn't too bad, but any time there's high pressure gas free inches from your face some danger is involved. That makes the AA design which favors broken bolts a real loser. You could argue that breaking more extractors and fewer bolts is better, but on a tactical type gun like an AR a common breakage that locks up the gun is bad too.

The correct solution was to make a new barrel extension that accepted a larger bolt head with sufficient steel to withstand the bolt thrust and sufficient space for a robust extractor. This is completely feasible and prototypes have been made but nothing standardized. AA didn't do this because Bill Alexander is an incompetent engineer. Now those unfortunate enough to trust him are stuck with time bomb guns.

 

[MASTARBLASTER]

First of all I would like to thank the moderator Walkalong , for playing the role of a devil's advocate, in suggesting that HE is one of the many of us, like myself who read these forums to acquire specific technical firearms knowledge from a network of vastly more knowledgeable and experienced firearms enthusiasts. Walkalongs strategy has been on point to cause Llama Bob to give a detailed answer to the Grendel cartridge design flaws he cited. An answer that LB quickly provided. Thumbs Up ! Previously, I had the impression that only the shallow bolt face depth was the only flaw in early production models, which were reportedly "fixed" by new type 2 bolts. The concise explanation of, " the correct solution was to make a new barrel extension that accepted a larger bolt head.." was clear and to the point. However, the merits of the 6.5 Grendel cartridge as a vast improvement over the 5.56 still appear valid but perhaps not in the the adapted AR platform lacking a new barrel extension.