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6.5 Grendel - Possibly the Perfect Utility Rifle

Because of it sheer pervasiveness of the availability of complete rifles, parts, magazines, ammunition and accessories, the possession and proficiency with the AR 15 family of rifles is considered imperative from the standpoint of exercising the will and means to provide one’s own self defense. 

DSC 0455With the War on Terror grinding on for over ten years  we have read and observed reports of deficiencies in the performance of the .223 round in urban combat environments involving masonry, vehicles and wood concealment being used by bad guys, we have felt that it was important to address the use of more potent rounds to address these concerns.  Not that any of us wish to inject ourselves into an urban combat environment, but most of us do in fact live in urban and suburban environments that would also provide similar terrain to bad guys that might be trying to inflict harm on us. 

As we have considered what to do to address this, we have evaluated the options of having other weapons available, such as a .308.  Our review of some of the options for a .308 is contained in other reviews on this site.  Another option that has been developed with military applications in mind is to utilize a different rifle upper receiver attached on the AR 15 rifle lower receiver.  What this provides is essentially two rifle calibers being used alternatively on the same rifle frame. 

In conducting research on the best viable options, it appeared to us that the best alternatives at this point in time is a 6.5 Grendel upper receiver on a standard AR 15 lower receiver. 

The 6.5 Grendel was in fact developed in order to enhance the capability of the AR 15.  Bill Alexander developed the enhanced round in order to fit the magazine well of the AR15, and worked with the AR gas system.  The results have been added penetration capability being able to be added to the AR 15.

6.5 Grendel build

When we first decided to build the 6.5 Grendel, our timing was very poor.  We had concluded our research and made our decision to build the 6.5 Grendel coincidentally in November 2008, and should have realized the impact of the results of the presidential election of 2008. Immediately following the presidential election, firearms, firearms parts and ammunition were nearly impossible to obtain.  At the time we had looked at the offerings of the very few manufacturers and decided to try to obtain the Alexander Arms 24”Overwatch.  This rifle upper was unavailable and there was absolutely no information regarding its anticipated availability.  We began watching MidwayUSA.com, and found that they had delivery estimates on the Sabre Defense 6.5 Competition model, so we placed an order, even though the upper was backordered until October 2009. 

One day in about April of 2009, the Sabre Defense M5 became available from MidwayUSA, so we cancelled the standing order and ordered the M5 immediately. Even though we got this rifle due to losing patience, when we finally took delivery of this upper, we were very pleased with the production quality, and the balance and feel of the completed rifle.  The Competition had a 20” barrel that we anticipated would give us better accuracy at longer distances, which was the primary reason we wanted this rifle. 

The M5 comes with a 14.5 inch barrel, permanently pinned with an A2 birdcage flash suppressor.  Although this is a really cool looking upper, with the full-length gas block, and the rail adaptor system that extends beyond the gas block, we had a concern that our impatience would result in a platform that would not provide the added performance to the standard AR platform to make it worth building. In some of our research regarding the 6.8 SPC and 6.5 Grendel, it was purported that  in the M4 models of barrels, the rounds are still burning powder when they leave the barrel, resulting in a muzzle flash, or signature, detectable by those at whom you may be shooting.  So, getting a 14.5 inch barrel was actually 10 inches shorter than desired. 

We were very impressed with the precision and clean production quality of this upper, and its related attachments.  The M5 upper came with a free-floated barrel, and a very precision aluminum quad rail.  We hated spending $1,250 for this upper, but when it arrived, we were so impressed with the production quality, that we got comfortable with the cost of it.  In fact, we were so pleased with the quality and feel of this upper receiver assembly we later decided to build a 5.56 AR with the Sabre defense M5 upper. 

The upper assembly was attached onto a Yankee Hill Machine (YHM) lower receiver that we were able to obtain from a gun shop that had one and the price was reasonable, especially considering the hoarding and speculating that was going on at the time.  The Lower receiver was built out using a standard DPMS lower kit.  This kit went together into the YHM stripped lower very nicely.  Everything in the DPMS lower parts kit fit very well into the YHM lower. 

We do not like a bunch of gimmicky add-ons on the rifle platform, because in a “need-to-use scenario”, simplicity is a lifesaver.  The more simple the setup, the fewer things to break, snag, fail, bend, etc.  One thing that we consider a “must have” though is the Ergo grip pistol grip on the lower.  This has been the most comfortable grip we have found for the AR.  Although it has a rubbery feel, its shape and contour have resulted in rifle that is very comfortable to carry, aim, and control. 

Another thing that we now consider a “must-have”, is the Magpul trigger guard.  It bows out to provide better clearance within the trigger housing for gloved hands.  But it also changes the feel on that area of the rifle, including filling in the normal gap between the pistol grip and the trigger guard.  This gap elimination adds a small amount of comfort to something that is normally not painful, but just constantly annoying. 

When putting this rifle together, we decided to evaluate one of the many new stock options available on the AR platform.  After significant consideration and research, we decided to take a chance on the VLTOR EMOD adjustable stock and tube combo.  We got the stock and buffer tube combination because we had to get a buffer tube anyway, and decided to just get the stock that had the matching mil spec buffer tube with it.  The fit of this stock is excellent, and we will likely replace some of the other standard M4 stocks with this VLTOR EMOD.  We do not receive any products for evaluation from manufacturers, so the number of products that we evaluate is not unlimited, but we evaluate enough products to be able to render an opinion about that product, and we purchase enough comparable products so as to usually render a comparison. 

We also decided to evaluate this rifle with the Trijicon TA 31 4x32 ACOG.  As our eyes begin wearing out with age, we have determined that the need for magnified optics is imperative just to assure an even chance in a defensive situation.  Along these lines, we decided to get the most magnification we could from a non-battery reliant shooting optic, that was rugged enough to perform as the standard sight for the rifle.  Based on our evaluations and study of this subject, we determined that the Trijicon ACOG would be the best overall long term solution for this rifle and its application.  The Trijicon ACOG (Advanced Combat Optical Gun sight) is engineered and constructed for heavy duty, reliable performance under adverse conditions.  The optics in the Trijicon scopes we have evaluated have been very clear, and the ability to acquire a target quickly without dealing with parallax, and other characteristics of scope tubes has seemed to be a good idea. 

Originally for this 6.5 Grendel project, we decided to mount the Trijicon 6x48 TA648308H Trijicon.  After waiting for availability, we finally acquired this excellent optic.  Once we mounted this optic onto the upper receiver of the AR, we realized that this was not going to work for us.  The 6x48 ACOG is very large and heavy, and once mounted onto the AR, the rifle became top-heavy and unwieldy .  Although the sight picture was incredibly crisp, and the 6 power magnification was great, we had a great concern about having to ever carry this weapon around for extended periods of time.  And for the size, we would probably be better served by variable power  long distance scope mounted onto the rifle.  Even though the 6X48 ACOG has a Picatinny rail on the top where you could mount a reflex sight, or some other sort of backup for close proximity targets, the backup would ride so high, that we felt that it would render the backup somewhat limited in utility. 

We also ordered the TA 75 quick release mount for this ACOG, and upon arrival found that the standard quick release mount does not fit the 6x48.  This killed this idea for us, so we returned the entire setup to MidwayUSA, and started over.

 We then ordered the Trijicon TA01-ECOR 4x32 ACOG.  Again, none were immediately available, so we waited until something came in, and upon arrival of this sight, we were absolutely impressed.  This optic is a truly incredible piece of equipment.  The sight picture through this 4 power scope is crystal clear.  The reticule is clearly illuminated with fiber optics and tritium so it is always readily visible in all shooting situations.  With our aging eyes we found the reticule gradient lines and markings to be illegible by sight, but we know what each of the lines indicates so we could discern its use without having to read them. 


Obtaining ammunition was also an adventure in 2009 and 2010, and there was almost no ammunition to be found for any firearms consistently for about a year following the election of President Obama.  We initially found some 6.5 Grendel from an individual who had obviously stockpiled all kinds of ammunition, and was later reselling it, at what we considered to be a reasonable markup.  So we scored some Wolf, Gold 6.5 Grendel.  Toward the end of December 2009, we directly called the headquarters of Alexander Arms, and spoke to a very pleasant employee who was very helpful and informative, and she indicated that they had ammunition readily available for sale, even though their website indicated otherwise.  We happily provided all of the requisite identification and they quickly shipped it to us. 

We purchased magazines from MidwayUSA that were manufactured by C-Products.  These were the only magazines anywhere at the time, but they have functioned very well.


Upon finally obtaining all of the parts and ammunition, a project that took us over a year to complete, we took this rifle to the range for evaluation.  We were finally able to test the 6.5 Grendel cartridge, the ACOG optic, the C-Products magazines and the ammunition.

This rifle was tested with iron sights and in zeroing the ACOG and the red dot sight that sits atop the ACOG. During testing; utilizing approximately 60 rounds or precious and rare ammunition, we did not experience any malfunction, mis-feeds, misfires, etc.  Everything has operated very smoothly.

The results were very pleasing and impressive.  First, we loaded the Wolf Ammunition, and sighted in the ACOG, and with only minor adjustments, we were consistently hitting 3 inch groups at 100 yards.  We then started for the 200 yard targets, and again, with minor adjustments, we were consistently hitting small groups of about 6 – 8 inches at 200 yards.  We found the recoil during the testing to be very tame, and we discovered this round to be very shooter friendly.  This is important from the standpoint of being able to place into the hands of a family member in a dire situation.  The recoil on this round is significantly lighter than the recoil on the AK 47, and we would not hesitate putting this in the hands of a small woman to use, as we anticipate that the recoil would be very tolerable.

We were impressed with the excellent performance of this rifle.  With the ACOG mounted on the rifle, it has a very comfortable balance and feel and quite natural to point and acquire a target. 

We were able to repeatedly make hits on a target from a non-bench rested standing position with the ACOG at 200 yards, which was very impressive to us since many rifles are too heavy to really shoot accurately without a bench rest. 

We had the opportunity to field test this rifle during some nighttime pig hunts in Florida. The rifle, as it is currently configured consists of a Sabre Defense 16” barreled M5 model of the 6.5 Grendel, equipped with the VLTOR EMOD stock, mounted with the Trijicon TA01-ECOS ACOG optic, and UTG xxx Weapon light.  Also on this rifle is the Ergo grip quick detach vertical grip. 

The sling on the rifle for the hunt was the Blackhawk single point, that attaches to the Promag sling attachment endplate we added to the rifle.  The night time pig hunt was a very good practical test for this rife.  Our hunting team consisted of two hunters in a tree stand that we had erected along a very heavily travelled pig trail, and two hunters patrolling the area radiating outward in the opposite direction of the tree stand.  This rifle was carried along for the patrolling and it performed very well.  When wandering around the swamps at night in Florida, one is extremely grateful to be carrying a light and a rifle.  This is sweaty, muddy, nasty business, while surrounded with the noises of an incredible array of large animal life. The woods are alive at night with all sorts of creatures; heard, but often not seen. 

The single point sling was actually very practical, as I looped the magazine through the sling in front, which enable me to have hands free for clearing vines, and moving palm fronds out of the way, and then quickly un-looping the rifle to bring it up to a shooting position.  The nights of our hunts were steamy and sweaty, but the light and the ACOG were always ready when needed without hesitation or fogging.  The ACOG mount was rock solid, despite many encounters with vines brush and fronds.  We had the opportunity to “field test” this rifle to do some nighttime hunting on private agricultural land in Florida, which we consider to be an extreme testing environment for any firearm.

During this field test, we were particularly impressed with three components of this setup:

1.The Trijicon ACOG performed veryThe view through this optic was excellent and clear. Throughout the night, we did not experience any fogging; even though it was ironically cold (for Florida), very humid and sweaty.

2.The UTG weapon mounted light was very reliable, and veryWe had attached the cable switch that comes with the light, as sold by Cheaperthandirt.com, and this switch demonstrated some excellent resilience and toughness.

3.The Ergo Grip Quick Detach vertical forward grip was great toThis has become one of our preferred forward grips due to its light weight, its durability and its quick detach function.  It simply works.


There are definite pros and cons to the 6.5 Grendel rifle platform:


  • Heavy hitting performance on lightweight platform – The performance of this round rivals that of the .308 without the cartridge weight, or rifle weight of the .308.
  • Very light recoil.  We cannot really discern any difference between the recoil with this rifle and the recoil of an AR 15 shooting a .223. 
  • Tremendous versatility with this rifle platform – This round can be used for ANY application; be it hunting, home defense or short and long distance precision shooting.
  • Unlimited accessories and enhancement available, since it is on an AR 15 lower receiver. 


  • Simply availability of everything 6.5 Grendel. 
  • Ammunition supplies are inconsistent and very expensive.  Surplus ammunition does not exist for this round.
  • Very limited number of suppliers for parts. 

The CONS of the 6.5 Grendel are finding relief in the near future, as there have been developments in late 2011, wherein the Trademark for 6.5 Grendel has been relinquished by its developer, Alexander Arms, apparently in exchange for this round to be standardized with the Sporting Arms and Ammunition Manufacturers' Institute (SAAMI)   There have been market forces brought to bear on Alexander Arms, as their protection of their Trademark disallowed the general use of it by anyone else, which obviously prevented other providers from jumping in with parts, rifles and ammunition for this round; seemingly dooming it to obscurity and eventual disappearance.  This new standardization should open the door for increased competitiveness for this round. 

We have been very pleased to hear about the developments pertaining to the release of the Trademark, as it will definitely open up the market for additional providers; solving the problems of selection, availability, and prices. 


We have concluded the 6.5 Grendel may currently be the ultimate rifle, because it has the ability to do about anything needing to be done with a rifle. 

The Sabre Defense upper was very well made, but we highly recommend avoiding doing business with this company, due to their inability, and/or unwillingness to communicate with customers.  There are just too many alternatives in the marketplace to tolerate unresponsiveness and quality inconsistencies like we have experienced with some of their other products. 

That being said, we highly recommend obtaining a 6.5 Grendel rifle in some form or fashion, acquiring ammunition to assure that the rifle can be utilized when needed, and becoming proficient with this round.  When we first started building and evaluating this rifle, it was likely to have been forced load your own ammunition in order to acquire ammunition for this rifle, but since 2011, the availability of ammunition has dramatically increased and we anticipate that with the Trademark being relinquished by Alexander Arms, ammunition will become more available and more affordable. 

We might even be as bold to say that the 6.5 Grendel should be the second rifle acquired after first acquiring an AR15 in .223.  In fact, having an AR15 will give you the platform for the 6.5 Grendel, and you could have two rifles in one of you have an AR15 with an upper receiver in .223 as well as 6.5 Grendel, and swap them out.  Two rifles for the price of….well two, but this may be the perfect rifle.DSC 0442DSC 0444DSC 0445DSC 0446DSC 0447DSC 0448DSC 0449DSC 0450DSC 0451DSC 0452DSC 0453DSC 0454DSC 0456DSC 0457DSC 0458DSC 0459

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