6.5 Grendel News

[TX65]

Recently, Bill Alexander of Alexander Arms received the following correspondance from Dr. Lou Palmisano. Bill Alexander and Dr. Palmisano authorized it's release.

For those readers unfamiliar with Dr. Palmisano, he is the original inventor of the PPC family of cartridges which is considered by many to be one of the top cartridge developments in history. In addition, Dr. Palmisano is one of the foremost and respected experts in the world on firearms and ballistics with 15 firearm and cartridge design patents to his name. Dr. Palmisano is a legend in the shooting world.

Here begins Dr. Palmisano's letter -

12/3/03

Dear Mr. Alexander,

Some time ago while reading about your propriety .50 Beowulf and .21 Genghis designs and your choice of the AR for both chambering, I thought to myself “Bright boys our friends from across the pondâ€!

Then I heard thru the shooting grapevine that you were experimenting with BR & PPC Bench rest cases. I concluded that this Bill Alexander’s work bears watching.

This October I received from a shooter the Shotgun News Article “Alexander Arms 6.5 Grendel†The Black gun bulks up by David Fortier and I read with interest since I had been working with similar combination in a single shot for years-

You picked a perfect bullet, improved and strengthened a very accurate case, and wed it to a fine weapon.

I cannot help but feel that you have taken the AR workhorse and turned it into a thourgh bred race horse!

I have a feeling that the NRA High Power Game will never be the same. The hunting crowd – Varmint to deer must be eagerly waiting while I am willing and ready to admit that the 6.5 Grendel could well become the new darling of the Bench rest Boys especially at 300yds, if the bullets and cases are held to the tolerances you have ordered!

However, as a fellow case designer I am compelled to say that I see one detaching flaw in this perfect 6.5 Grendel AR concept that you have developed and that is ---That I didn’t think of it first.

Congratulations and Good Luck

Lou Palmisano

-----

The first 6.5 Grendel AR15 production model is being released on February 12, 2004 at the SHOT Show in Las Vegas. In addition to AR15 rifles, upper receivers, magazines, ammunition, brass and dies for reloading will be available. Dealers are now able to begin placing orders.

 

[Lofland]

Knowing only a little about rifle ballistics, I learned a lot from your www.competitonshooting.com site. Some of the Internet ballistics gurus are pushing the 6.8 x 43 cartridge very hard as the best replacement for the 5.56mm. Remington will reportedly be manufacturing the caliber next year. Have you examined the data on this round? How would you compare it to the 6.5 Grendel? Does Alexander Arms have anything official to say about their competition? Have any ammunition companies shown an interest in manufacturing the round? HK is pushing the XM8 in 5.56 as a replacement to the AR15, have you heard anything about HK considering a heavier caliber for the gun?

BTW, the Medesha 6.5 PPC rifle shown on your site looks like one very very nice setup, what does something like that cost? I couldn't find any price figures for a rifle like that on the Medesha Firearms site.

 

[TX65]

Thanks for your post,

Naturally, people have come to compare the two rounds (6.8 SPC and 6.5 Grendel) and ask which one is better. Obviousaly, each development team has a belief in their round and it's performance. Factually, at this time, neither party has been able to test rifles and cartridges in a head to head race so it would be inappropriate for either party to comment on what they have no direct experience on. I am sure an independent party will conduct credible tests when the rifles and ammunition are available.

Keeping that in mind, I can offer the following about the 6.5 Grendel.

The 6.5 Grendel is based on what is considered one of the best cartridges ever developed - the 6 PPC. The 6 PPC has dominated accuracy competitive shooting for over 25 years and most accuracy world records are held by the 6 PPC. In addition to outstanding projectiles, what gives the 6 PPC its edge is the design of the case and it ability to have extremely uniform and consistant combustion. So proven is this efficiency, that the PPC case is the design philosophy that forms the foundation for every "short and fat" cartridge on the market today.

The 6.5 Grendel builds upon the proven engineering and performance acheivements of the 6 PPC by expanding it's potential with the use of the 6.5 mm bullet offerings. Why 6.5 mm and not some other caliber? 6.5 mm is the largest caliber that provides a large number of high to very high ballistic coefficient and sectional density bullets in the proper weight range to achieve competitive performance in a cartridge of this size. Currently, there over 30 different 6.5 mm bullets available from Lapua, Nosler, Sierra, Hornady, Barnes, Speer and Norma in the 85-130 grain weight range to meet individual needs. In addition, 6.5 mm bullets in this weight range are considered to be outstanding for hunting of game including deer, hogs and antelope.

Specifically, the 6.5 Grendel case is an improved version of what many would call a 6.5 PPC. Alexander Arms, working with Lapua engineers, have made design improvements to increase the capability and durability of the round for use in platform such as the AR15. As Dr. Lou Palmisano indicated in his letter, he is enthused with the design changes and believes they only add to his well proven PPC without detracting from the qualities that led to it's standing. It is this belief that has motivated Dr. Lou Palmisano to publicaly comment and support this evolution of the PPC he developed.

As it relates to the AR15 platform, the PPC case is the largest case capacity cartridge that will work without doing radical changes in the rifle's design. In addition, the PPC case, due to it's 1.505 inch length allows magazine length feeding of a wide range of 6.5 mm bullet offerings.

Lapua is producing the brass and Alexander Arms is the importer and distributor of this new brass which will be sold empty for reloaders and in loaded ammunition which Alexander Arms produces in their ammunition production line. I will be posting on http://www.competitionshooting.com shortly the cost of Alexander Arms's complete rifle, upper assembly, magazines, ammunition, brass and reloading dies. Please send me a message and I will be happy to outline the specifics of the 6.5 PPC test rifle pictured on competitionshooting.com.

As far as H&K and any projects they have in development with the defense department. H&K is a firearms manufacturer and will build firearms in any cartridge that the customer (military ) wants. If the military decided to make a change from the 5.56 NATO, any development H&K has done for a firearm chambered in 5.56 NATO can be readily changed provided the new cartridge maintains similar dimensions and operating pressures of the 5.56 NATO.

 

[Cosmoline]

Wider range of bullets? Excellent. That was one of the things about the new 6.8 SPC that has made me think twice about it. After all, why choose the 6.5 to 7mm range and then create a cartridge with an OAL which precludes the effective use of any of the "magic" bullets. A 140 grain 6.5mm would have sectional density superior to any existing US small arm, including anything in the 7.62 NATO range short of a 190 grain match bullet.

What kind of twist rate are they going to use for the AR uppers?

 

[TX65]

Cosmoline,

I have tested the 6.5 PPC with the 142 Sierra Matchking, but that was a while ago and I wasn't using what worked out to be the best powder. I will be testing later this week with a 141 grain bullet with the proper powders. While there will be a velocity degradition from the 123-128 grain bullets, I don't have the amount of degradation available at my current location. One point of this testing it to detemine if the amount of velocity degradation is offset by the increase in 70 ballistic points going to the 141 bullets.

The production rifles have a 8 twist stainless steel barrel.

 

[ks_shooter]

This has been stated on other forums, but I thought I would add it here:
The cartridges were designed for different purposes. The 6.5 Grendel is a highly-accurate long-range cartridge that will have many applications in the target-shooting, hunting and even, perhaps, military sniping roles. It is optimized for exterior ballistics. The 6.8 SPC was designed to make the M4 a more potent threat out to distances of about 300 m. It was optimized for terminal ballistics.

The 6.8 SPC was designed to work well in a short barreled carbines and provide dramatic fragmentation at longer ranges than M885. I don't know how the 6.5 Grendel would perform in a 14" barrel, I don't think anybody has tried it.

The 6.5mm bullets that earned their reputation hunting big-game would probably not be the best choice for close combat with un-armored adversaries. As I understand it, the 6.8 SPC developers looked at a large range of bullet calibers and weights and settled on the one that would maximize the terminal ballistics of the round.

Personally, I am more interested in the 6.5 Grendel in an SPR configuration. But, I don't have to clear houses with bad guys shooting back at me.

 

[TX65]

KS_Shooter

Thanks for your post.

Terminal ballistic studies have been performed by an independent party using the 6.5 Grendel. Those results are to be published in the near future in a "no spin" format. The 6.5 Grendel design team is quite pleased with results of the tests using off the shelf currently available bullets that anyone can purchase. However, given the military design experience of at least two of the members of the 6.5 Grendel team, a bullet can easily and quickly be designed to yield various desired terminal effects.

The 6.5 Grendel and its parent, the 6.5 PPC have been fired in 14, 12 and 10 inch barrels and are very effective. In addition, the 6.5 PPC has been used with success for silhouette shooting. In addition, I have tested the 6.5 Grendel out to 1,000 yards in a 16 inch barrel AR15. While a 16 inch barrel is not my personal preference for 1,000 yard shooting, the cartridge and rifle acheived a 6.5 inch 10 shot group fired from a bipod.

The 6.8 SPC is using a 115 grain HPBT and bullets of similar construction and design. As a point of reference, Sierra makes 6.5 mm bullets in the exact same configuration in 107,120, 140, 142 and 155 grain weights. In addition, there are numurous other bullet manufacturers who make 108,114,119,123,128,130,139,140,141,144 and 147 grain 6.5 mm bullets of similar design and construction.

You have to remember that a match HPBT bullet by it is very nature has a tendancy to fragment upon impact with a soft tissue target and that is one of the reasons why all of the bullet makers do not advise their use for hunting game animals. In fact, fragmentation can be increased on any HPBT bullet by incorporating certain design features which I will not discuss in a public forum.

 

[ks_shooter]

TX65,

Thanks for sharing the info on the short-barreled 6.5 Grendel. I agree that bullets are bullets (so to speak) and that the 6.8 SPC and 6.5 Grendel are nearly the same caliber. The same size and type of bullets at the same velocity behave the same regardless of which case they are propelled from.

I was under the impression, though, that the 6.8 SPC case was designed with the shoulder pushed forward to allow for greater powder capacity in the case. This allows the round to generate higher velocities (at least at short to mid-range distances with it's lower B.C bullet) than the 6.5 Grendel, insuring a better probability of bullet fragmentation. This same case design feature has the negative consequence of limiting the length of bullet that can be effectively loaded. If the Grendel can push the same bullet as fast as the 6.8 SPC I would have to say that the 6.8 SPC would have no advantage.

What about reliability of feeding/extracting of the two rounds? I thought I read that the 6.8 SPC case had more case taper than the 6.5 Grendel. This could give the 6.8 SPC and edge in reliability over the 6.5 Grendel in harsh conditions.

 

[TX65]

Hi KS_Shooter,

Case capacity is simple geometry of a cylinder with only the added twist of the shoulder area.

A 30 Remington case has a .421 head diameter, a PPC has a .441 head diameter. At equal case length, body taper, shoulder position and neck length, the PPC would have greater case capacity due to the .020 increase in case diameter. In order for a cartridge based on the 30 Remington to have equal capacity to the PPC, the case would have to be longer then the PPC in the body and / or shoulder area.

Ok, now taking the 6.5 Grendel vs. the 6.5 PPC. One of the design changes in the 6.5 Grendel was pushing the shoulder forward thereby shortening the neck. As a result of this change, case capacity of the 6.5 Grendel is greater then the 6.5 PPC. However, the increase has been held to a point where it would not have an adverse impact on the combustion efficiency of the proven PPC design.

Can the 6.5 Grendel fire an equal weight bullet at a velocity equal to the velocity information released on the 6.8 SPC from the same length barrel. The simple answer is yes.

However, bullets are not bullets even though there is very little difference in bullet diameter between the 6.5 and 6.8. Take a 6.8 Hornady 110 grain VMAX, per Hornady, that bullet has a ballistic coefficient of .370. Now, take a 6.5 mm Lapua 108 grain Scenar, that bullet has a ballistic coefficient of .473. So you have two bullets, 2 grains in weight difference, the 6.8 with the advantage of a polymer tip but even then the 6.5mm has 103 additional ballistic points.

At equal muzzle velocities, 103 ballistic points makes a big difference at 300, 400, 500 yards and beyond because the bullet with the higher ballistic coefficient will have higher retained velocity at any distance from the muzzle. If fragmentation is the goal and fragmentation occurs only above a minimum velocity threshold, the bullet able to maintain velocity above that minimum threshold for a greater distance would have greater utility.

I have not personally fired the 6.8 SPC and cannot comment on the reliability.

My original 6.5 PPC rifle feeds as well as any of my 223 Remington rifles and the 6.5 Grendel rifles feed even better. The only failure I have ever had was blowing a primer when doing load development and I went one step too far.

As far as harsh conditions, I have shot my rifle in rain and freezing rain. When it is 25 degrees and when it 100 degrees and 95% humidity. I typically shoot 200 rounds at a time and never clean the rifle when I am at the range. I sometimes head back to the range for another shooting session without doing nothing more then an external wipe down. I have yet to ever have a function problem due to the environment or not being anal about cleaning my rifles.

 

[ks_shooter]

From what I have read about the 6.8 SPC development, it was run by soldiers and not politicians. It may be past the point of no return by now, but I hope they take time to look at the 6.5 Grendel (actually 26 Grendel, and you have to say it with a British accent ). Our soldiers deserve the best we can give them.

 

[uglygun]

All we need to happen inorder for this cartridge to truely take off and make a real success out of Alexander Arms, is for the AW ban to sunset in 2004 and allow PROPER high capacity magazines to be manufactured specifically with this cartridge in mind.


That would be truely wonderful. I truely believe that's the only reason behind why PPC AR15s are not as popular as they could be, there is a very small supply of decent capacity magazines out there that work well with the 7.62x39mm cases.


Too bad this cartridge or one very similar to it wasn't around 40+ years ago as the AR15 was being developed, very likely that it could have eclipsed the 5.56x45mm in terms of what was being sought both performance wise and logistics wise.

 

[TX65]

KS_Shooter,

I am the one with Texas accent so I have been told.

Uglygun,

Alexander Arms already has a magazine with 25 round capacity for military and law enforcement customers. This magazine has the exact same external dimensions as the standard issue 30 round 5.56 magazine.

As of 12/16/03, Distributors and Dealers are able to begin placing orders for the 6.5 Grendel.

The initial rifle model is called the "Overwatch", it has

Forged flat top upper receiver
24 inch lapped, stainless steel barrel with a 1 in 8 twist
Composite free float hand guard with dual studs for bipod and sling mounting
Scout Rail allowing forward mounting of scopes
Match trigger
Soft carry bag
10 round magazine

In addition to the complete rifle, the upper is available individually. Customers are also able to purchase magazines, brass, reloading dies and loaded ammunition. Loaded ammo will be available in three loadings. 1. Lapua 123 grain Scenar, 2. Nosler 120 grain Ballistic Tip and 3. Speer 90 grain TNT

Initial product shipping will be in late February or early March.

Additional rifle models will be released in 2004.

 

[uglygun]

Alexander Arms already has a magazine with 25 round capacity for military and law enforcement customers. This magazine has the exact same external dimensions as the standard issue 30 round 5.56 magazine.

Yeah, I'm aware of that....

It's just that it is a darn tootin shame we aren't legally allowed to possess/purchase those mags unless the AW ban sunsets. The mag might have the same external dimensions as a regular 5.56x45mm mag but the subtle nuances like how the mag is curved for proper stacking(not knowing case taper angle), how the feed ramps are designed, or if the reinforcement ribbing is modified in the mags intended for the 6.5 Grendel. Those are all the things that give me reason for wanting the mags intended for the 6.5 Grendel as opposed to trying to convert 5.56x45mm mags.


It's high time that stupid AW ban went away so that way some manufacturers can come along and make true high quality mags for all the various niche uppers that have come along and are somewhat handicapped by selection.

 

[adad]

Both rounds sound great.

How much would "military" 6.5 Grendel rounds weigh? (This would, of course, require speculation on your part about which bullet would make the best military round, but that's okay - speculation's why we're here! ).

From the definitive thread on the 6.8x43 over on TacticalForums: "30 rounds of 5.56 mm M855 weigh about 0.8 lbs. 28 rounds of 6.8 mm ... weigh roughly 1 lbs." And, per the same thread, "28 rounds of 6.8 mm fit in magazines the same size as 30 rd 5.56 mm mags."

Here's that thread: http://64.177.53.248/ubb/Forum78/HTML/000512.html

If correct, 28 vs 25 rounds in a standard 30-round GI mag might be significant as far as military use is concerned... And weight is a consideration too...

 

[ks_shooter]

Can both of these rounds be accommodated with just a barrel/bolt change? I thought I read in the Shotgun News article that Alexander Arms had modified the upper to relocate the ejection port for the 26 Grendel. I have a Bushmaster upper that would be a prime candidate for an upgrade to one of the calibers if all I needed was a new barrel and bolt.

 

[TX65]

Adad,

As you mentioned, it will vary with the weight of the bullet. As a sample,

Using a Lapua 108 Scenar with a .473 ballistic coefficient, you would be looking at a loaded cartridge weight of approximately 250 grains which equates to 28 loaded cartridges per pound. Therefore, 300 cartridges would weigh 10.71 lbs.

A 5.56 NATO with a 77 grain bullet is going to weigh approximately 210 grains which equates to about 34 cartridges per pound. Therefore, 300 cartridges would weigh 9 pounds.

In comparison, that would be a difference of 1.71 lbs for the same number of cartridges.

However, given the mild operating pressure of the 6.5 Grendel, it also lends itself to make use of composite case technology (not referring to caseless) and other developing technologies which could plummet the cartridge weight significantly for a military application.

In the thread you highlighted, Dr. Gary Roberts, DDS posted on 10/9/2003 the following

""Existing 5.56 mm magazines can easily be modified to shoot both 6.8 mm and 5.56 mm, using a new follower and slight modification to the feed lips. Since the magazines can still shoot 5.56 mm, they are still BATF legal. When modified this way, a typical GI 30 rd 5.56 mm mag will take 25 or 26 rounds of 6.8 mm. FWIW, all of our initial SPC testing was done using existing 5.56 mm magazines, NOT the new 28 rd PRI 6.8 mm specific mags.""

As a note, the PRI 6.8 SPC specific 28 round magazines are reported to be longer then the standard dimensions of the 5.56 NATO 30 round magazines. Given current regulations, the PRI magazines as well as Alexander Arms high capacity magazines are only available to law enforcement and government agencies since they are new (post 1994) manufacture which is what the 1994 law relates to.

In my years of testing with the 6.5 PPC, I used modified .223 and 7.62x39 AR15 magazines doing slight bending of the feed lips and no follower change. The modification takes all of 2 minutes per magazine. As a note, many times, 5.56 NATO magazines need slight bending of the feed lips to work reliably with .223 Remington.

KS_Shooter,

The modification to the ejection port is just a slight opening up of it. Two of the orignal prototype rifles functioned reliably without this modification. This feature was done for competitive highpower shooters who must single round load in portions of the course of fire.

 

[chevrofreak]

Video of the 6.5 Grendel

 

[adad]

Thanks for the info TX65!

So, they're similar in weight (for similar weight bullets) and fit about the same number of rounds in a standard 30 round GI mag... What do you give up in terms of terminal performance (compared to 6.8x43)? Can you give any gel testing info on the 108gr 6.5?

What's the ballistics for a 108gr (drop/speed at 100 yard intervals)?

Thanks!

 

[TX65]

Adad,

Independant ballistic gelatin tests have been performed and they are to be published shortly. The independant party who performed the tests is compensated for those tests and writing about them by the publication, it would not be appropriate to release the data in a public forum prior to them appearing in the publication.

Given the ability of both cartridges to operate at the same velocity, the 6.5 mm with a 108 Scenar bullet will impact any target at a higher velocity due to it's superior ballistic coefficient. In addition, since terminal energy is a relationship between velocity and projectile weight, the 6.5 mm 108 will have higher terminal energy levels on target.

Here is the data for the 6.5 mm 108 Scenar at a MV of 2650 fps from a 16 inch barrel. Bullet drop is based on a 300 yard zero and sight height of 2.5 inches above the bore line.

Range Vel Energy Drop
0 2650 1684 -2.50
100 2534 1540 +4.35
200 2421 1405 +5.48
300 2309 1278 0
400 2199 1159 -13.17
500 2091 1048 -35.33
600 1985 945 -68.05
700 1882 850 -113.21
800 1783 762 -173.06
900 1688 683 -250.24
1000 1597 611 -347.73

Note - As I stated earlier, my preference for shooting at 1,000 yards would not be a 16 inch barrel. A 24 inch barrel would increase muzzle velocity to 2800 fps+ with the 108 grain Lapua Scenar.

 

[Glock Glockler]

Tx65,

Where did you calculate those ballistics from? I plugged that info into the calculator and this is what I came up with. This was using a 108gr Lapua Scenar with a BC or .478 @ 2650fps.

Range 0 100 200 300 400 500
Velocity - ft./sec. 2650 2469 2296 2130 1972 1821
Energy - ft.-lbs. 1684 1462 1264 1088 932 795
Path - in. -1.5 2. 1 0.0 -8.7 -25.1 -50.5 -86.3

 

[TX65]

Hi Glock Glocker,

I used RSI Shooting Lab set at a "G5 standard boattail drag profile" which would be correct for both the 6.5 and 6.8 bullets as HPBT designs. In addition, this drag profile matches the real world scope adjustments I make for long range shooting.

Looking at the data you generated, your calculator used a "G1 flat base drag profile" which is the incorrect drag model for boat tail bullet designs. Your calculation would be correct for a flat based bullet.

 

[Lee F]

TX65,
Who are the dealers taking orders for this upper? Any idea about if the reloading components will be ready before the rifles? Thanks.

 

[TX65]

Lee,

If you are interested in ordering the Grendel, go to http://www.competitionshooting.com and send an email with your inquiry. Individuals making an inquiry will receive an email notification in January with information to order uppers, magazines, reloading dies and brass.

First deliveries will be in late February or early March.

TX65