Previous Post
Next Post

Usually TTAG reviews guns that we’ve borrowed. Over the next couple of months, I’m going to review a few guns that I personally own. We’ll kick it off with a heck of a target gun built by Precision Firearms in West Virginia. This beast, called the Enterprise Mod I, is chambered in 6.5 Grendel and features some unique touches.

Ordering a rifle from Precision Firearms is as simple or as complicated as you’d like. They usually have a few in stock on the site, ready-to-ship, but only a few. More often pre-built rifles will hit their Facebook page, up for grabs at a reduced price but never getting listed on PF’s actual website.

The vast majority of PF guns, though, are custom-built to order. There’s a base model, and then the buyer can select basically everything from barrel brand and length, barrel profile and any fluting, muzzle treatment, handguard, stock, grip, trigger, charging handle, cerakote on various parts, and more.

My rifle features a stainless steel Bartlein barrel with 1:8″ twist, 5R rifling. It’s a whopping 24″ long with a fairly heavy, straight profile and ball dimpling on nearly its entire length.

PF machines custom billet upper receivers for its Enterprise rifles, and they feature a right-side, forward charging handle. This knob is bolted directly to the bolt carrier and reciprocates with it.

If you can deal with the bit of added width, I happen to be a huge fan of the bolt-mounted charging handle. Not only does it work great for its titular purpose, it’s an exceptional forward assist and it does triple duty as case deflector. Especially with a large optic, it’s in a more convenient, easier-to-manipulate location than the standard AR-15 charging handle.

Unlike most side-chargers, this design still allows for the use of a standard charging handle. PF provides a few choices, and I went with the good ol’ BCM Gunfighter with medium latch. I never use it.

Up front is Precision Firearms’ own LMD Brake. The barrel threads are cut so the brake is perfectly timed when snug without the use of a crush washer or other spacer.

The LMD Brake reduces recoil by about 69% on a 5.56. That was good enough for a third place finish in Muzzle Brake Shootout #2 and fourth in the .308 Muzzle Brake Shootout. It manages this impressive performance without excessive concussion and with no blast for the shooter, while mixing in just a bit of muzzle rise and drift control. I also chose this brake for a custom .223 “DMR” upper build that I finished a few months ago (which otherwise has nothing to do with PF).

Behind the brake and over the barrel is a Seekins Precision SP3R handguard. Again, PF gives you the option of choosing between a handful of default offerings, or call them up and specify basically anything on the market.

Inside that handguard is an SLR Rifleworks adjustable gas block. This gives me the easy ability to tune the system for when I’m shooting suppressed (which is most of the time).

Inside the Precision Firearms 7075 billet lower receiver is the excellent Geissele SSA-E trigger that PF has taken the liberty of tuning up for an even crisper, cleaner break. This is the default trigger but, as with basically anything on the gun, other ones can be chosen instead.

Behind the trigger is a Battle Arms Development ambi safety, and behind that is a tensioning screw that removes any slack between upper and lower receivers. As both receivers are machined from blanks by Precision Firearms, they fit together very precisely and the screw isn’t actually employed. It may be handy if I want to slap other uppers on this lower, though, and presumably that’s why it’s included.

Inside the upper, the bolt carrier group is nickel boron treated and the bolt face and lugs are trued and lapped to the barrel extension, which is trued to the receiver and to the barrel, which is chambered by Precision Firearms to their specs.

Field stripping the upper, due to the fixed charging handle, requires removing the handle first. This is easily achieved with a hex wrench of the same size typically used for the pistol grip bolt. Once it’s off, everything else is as usual.

Unique receiver parts are rounded out by the Battle Arms Enhanced Modular Magazine Release and a PF-branded Hogue Overmold grip.

Finally, at the rear of the Enterprise Mod I (at least by default) is a Magpul PRS stock on which I’ve mounted an Accu-Shot Monopod.

When it all comes together, the end result is a fantastically tight firearm. Everything fits perfectly and works perfectly. Every moving part is as smooth and flawless as I’ve felt on an AR. Whether it’s the takedown pin or the safety or the trigger, it’s tight and smooth and precise.

And don’t even get me started on the action. Slowly rack the charging handle and you’ll be rewarded with the buttery smoothest action you’ve ever felt in an AR. It’s like a hand-lapped 1911 but without the bump at lockup. In fact, the Enterprise Mod I locks into battery so perfectly smoothly that there’s physically no way to lower the bolt without it going fully into battery.

On my other rifles, if I ease the bolt forward slowly enough it’ll stop at some point when the bolt lugs try to lock up with the barrel extension lugs. On one or two of those guns, the carrier needs a head of steam to lock up properly. That isn’t the case with the Enterprise. It slides into battery like hot greased butter.

Despite what you might expect from precisely fit parts with tight clearances, this gun is also fully reliable. Even plenty dirty and bereft of lubrication, it just runs and runs.

It can shoot, too. With my SIG Optics TANGO6 5-30×56 scope mounted up and ammo the Enterprise Mod I doesn’t like, it’s a 1 MOA rifle:

Literally group after group after group with four different ammo loads from three manufacturers almost always within a few thousandths of 1 MOA. As usual, we’re looking at five-round groups at 100 yards.

With ammunition that the gun likes a little more but doesn’t love — in this case Federal American Eagle 120 grain OTM and a load from Precision Firearms using a 123 grain Sierra MatchKing projectile — it shoots from 0.6 to 0.8 minute:

At 400 yards, this approximate accuracy was maintained:

With the three loads I’ve found so far that the rifle does really like, the Precision Firearms Enterprise Mod 1 6.5 Grendel is a half MOA or better gun. More like better, actually, when I do my part:

Precision Firearms ammo with a 130 grain Berger VLD Hybrid shoots about half minute.I was very happy to find a factory load that the Enterprise shoots lights out. As a lot of shooters on the 6.5 Grendel forums have found, Hornady’s BLACK ammo with its 123 grain ELD Match projectile is extremely accurate. In this gun its good for consistently sub-half-MOA, five-round groups.

The best round, though, through this PF has been PF’s own. Firing a 120 grain Lapua Scenar-L pill at 2,550 fps, this load is always handily sub-half-minute for me and I’ve shot a few 0.3x MOA groups. So, 0.41-inch or smaller maximum center-to-center spreads.

It’s certainly nice stuff, but at $1.58 per round it’s fairly expensive as 6.5 Grendel goes. MSRP on the Hornady BLACK is $1.10 per and it typically retails for more like $0.90 per. Of course, it isn’t quite as accurate, is it? I’ll be testing Federal’s Gold Medal Berger soon, as it has proven fairly amazing in a couple other calibers, but then we’re back up to about $1.50 a pop.

Fired pretty rapidly at the head of a steel torso target at 100 yards, the rounds stacked on top of each other. Well, four out of five rounds agree.

After shooting my Enterprise for almost a year now, if there’s anything I’d change it would be the barrel length. 6.5 Grendel simply doesn’t need this much barrel — it’s perfectly happy on an 18″ tube, for instance, and is better-suited than 5.56 on short barrels. On anything, oh, 20″ and under it’s an awesome caliber for hunting and, shall we say, “tactical” uses.

However, I built this rifle for shooting off a bipod or other rest or object. The extra barrel length and weight — especially with a pound of suppressor affixed — makes it more stable. Though it’s also likely more sensitive to harmonics and POI shift as it gets hot. Mostly to try and cut down on those two effects, I may eventually send the upper back to Precision Firearms and have them chop a few inches off this gorgeous barrel.

With half the recoil of .308, compatibility with standard AR-15 receivers, and about 1,900 ft-lbs of energy with a slippery 6.5mm bullet, it’s easy to see the appeal of the Grendel. Oh, and how about Wolf ammo for under 24 cents per round, shipped? I promise, I’ll try some Wolf eventually and will report back (along with Federal Gold Medal Berger results).

While a custom-made rifle from Precision Firearms won’t come cheap, it will be accurate, precise, and smooth like you wouldn’t believe.

Specifications: Precision Firearms Enterprise Mod I 6.5 Grendel

Billet 7075T6 Upper and Lower
Barrel by Bartlein, Krieger, or Lilja
Threaded 5/8×24 with Precision Firearms 6.5 LMD Brake (target crown available for $125 less)
PRI Carbon Fiber Handguard in black or natural weave
Precision Firearms Hogue Grip
SuperMatch NiB Side Charger Carrier Group
Geissele SSA-E 2-stage Trigger tuned by PF
Ambi Safety and Extended Magazine Release by BAD
Magpul PRS stock
Barrel fluting options, cerakote, other triggers, handguards, bipods, etc. all available on request
MSRP: $2,800 in standard configuration (add $125 to $200 for barrel fluting, depending on choice)

Ratings (out of five stars):

Accuracy * * * * *
I want to whine about ammo pickiness but even the stuff it doesn’t like shoots minute of angle. Even “weird” loads like American Eagle 90 grain Speer TNT. Bottom line, though, is that it’s a reliable semi-auto rifle that’s shooting even factory ammo sub-half-minute with me behind it, and that’s five star badass.

Ergonomics * * * * *
Absolutely amazing. The sole argument against the ergos would be the long, heavy barrel but I stuck with that on purpose for shooting off a rest. For more of an all-around rifle, I’d chop the barrel down to 18″ and probably run a lighter profile, and swap the stock out for something better-suited to hunting or defensive uses. Basically, it would be more like PF’s Arion Type I.

Customize This * * * * *
Precision Firearms is a custom manufacturer and builder. If you don’t like how I spec’d mine, spec yours your way. At the end of the day, it’s an AR-15.

Reliability * * * * *
I’ve shot hundreds of rounds of ammo from 90 grain to 130 grain, suppressed and not, in freezing temperatures and 103 degree temperatures, with lube and dry and dirty, and it has never hiccuped. It’s crazy smooth and precise, yet confident.

Value * * * *
On the AR-10 platform it’s easier for me to see prices of high-end guns hitting the $3,000 mark and think, “oh, okay, sure,” but on the AR-15 it’s a tougher pill to swallow (even if ammo is cheaper). When all is said and done, though, everything on this rifle is as good as it gets. You wouldn’t save a lot of money doing it yourself while choosing parts of this quality. And Precision Firearms does the most important parts — barrel work including chambering, extension, receiver fit and truing, etc. — and does it well. That’s where the sub-half-minute accuracy out of a reliable semi-auto comes from.

Overall * * * * 1/2
The PF Enterprise Mod I is a premier, but expensive AR-15 with somewhat limited utility. I may eventually have 4-6″ chopped off the barrel and find that last half star. Of course, Precision Firearms is a custom manufacturer so their rifles can be anything you desire. But they’ll always be accurate, precise, and oh-so-smooth.

Previous Post
Next Post


  1. Great review, thank you. And great rifle. Don’t think I recall ever hearing of that manufacturer. Made me look them up.

    You mentioned “harmonics” and later state that the fluting was ‘optional’. Did you choose a fluted barrel or did you choose a barrel and have it fluted?

    Any guru-title-worthy persons out there wanna weigh in on the harmonics aspect?

    If the ball-dimpling was merely to lighten the bull barrel with no other effect on ballistics aspects of the firearm, I’d think that was an option. If the dimpling of the barrel extended the life of the barrel by heat-dissipating surface area, I would think that was better. If it increased rigidity of the barrel without reducing overall barrel life, I would think that was an excellent reason to do it. But without some of those, I don’t know that I’d bother with something that’s going to be shot off of a bi-pod or bag (weight wise).

    Thank you again.

    • Judging by the photos, my assessment is that the dimpling does not significantly increase the barrel’s surface area, nor does it significantly decrease its weight.

      And, this is pure conjecture on my part but I would guess the dimpling decreases strength/rigidity more than it affects weight or surface area. It does not compare will with traditional fluted barrels.

      It’s something extra the manufacturer can do to add to the net profit and perhaps the tacticoolness factor.

    • It’s mostly aesthetics. There is a lot of dimpling and they’re fairly deep, so I’m sure the metal removed adds up to a not entirely trivial amount of weight but, yeah, it really wouldn’t matter either way for this particular use and it’s less metal than most fluting would remove.

      PF is a custom shop and they get these barrels as blanks. You could have them turn your barrel of choice down to whatever diameter and profile and length you wanted, leaving it plain or having it fluted in various ways or dimpled or whatever. Bead blast it, polish it, cerakote it, etc.

      I really don’t think it’s better or worse for harmonics or whatever, either. A barrel is going to wobble and flex and vibrate as the bullet travels down it. The amount the muzzle moves could be more with a longer barrel and/or the difference between different ammo loads could be more. The amount it moves due to heating up could be more than with a shorter barrel. Really, these aren’t topics I’ve researched extensively (other than understanding how harmonics affect accuracy and relate to hand loading ammo and running ladder tests, etc) on the mechanical engineering sort of side. But I do know that going to an 18″ barrel wouldn’t negatively affect accuracy though I’d lose a bit of velocity. I’m just *guessing* I’d see less POI shift if I get the thing particularly hot.

  2. I’ve met mark PFs owner and he’s a super nice guy. They always have a stand at the GAOS in Harrisburg, even after having a 9mm SBR stolen from them 2 years ago. One of their rifles is definitely on my bucket list.

    • I actually stopped by their booth briefly at GAOS this year out of curiosity. Seemed like nice folks. Anybody have any experience with ordering 6.5G ammo from them? They offer 20+ load options on their website, but they’re clearly a specialty loader rather than a true factory source. So, potential issues like actual stock status, component availability, and turnaround times come to mind.

  3. I own a PF Equinox 1 rifle in .223 Wylde with the 24″ Bartlein barrel and it is by far my most accurate semi auto. Even with milsurp 5.56 my groups are sub MOA at 100 yards. With 77gr Black Hills ammo my groups are the size of a nickel. I put in an order for one of their Terminus III bolt guns in .300wm back in May and I am still waiting on delivery. Mark does great work and it is always worth the wait!

  4. Honestly, that’s more affordable than I was expecting. That’s off-the-shelf SCAR pricing. That seems very reasonable for a custom made precision rifle.

    • Ya. Nice to think there’s something out there for ~ reasonable money that’ll really make you a better shooter (or prove you ain’t one).

  5. I built a precision 6.5 Grendel AR that i’ve been shooting for a few months. It of course doesn’t have the golf ball drilled barrel or side charger and probably lacks the premium parts of this rifle. I didn’t build this rifle to lug around so it is heavy weight coming in at 12lbs. It has a 22″ stainless bull barrel I bought from JSE surplus, PSA billet upper and lower, Seekins rail 13″ which is the same as the rifle above but but shorter, Mechforce .308 muzzle brake, Anderson BCG, PRS stock, and CMC trigger set for 3.5lbs. The optic is a Bushnell Elite 10x fixed that works fine for the ranges I am shooting at which so far has been a max of 400 yards. I’ll upgrade the glass eventually.

    With three different types of ammo tested it’s been a decent performer. The Wolf 110 grain loads will shoot about 2.5″ groups at 100 yards. Although the price per round is almost the same as 7.62×39 so it’s great for plinking. The PPU 120 grain loads are around .9″ at 100 yards. Hornady 123 grain Match is around .6-.7″. I have some Hornady black ammo but haven’t tested it yet. For a $1200 rifle, I am pretty darn happy with it’s performance.

  6. Not word one about weight? It’s a great, great shooter and a fine gun. It used to be said that “only accurate guns are interesting.” But in the last couple of decades accuracy has become a almost given in heavy guns. And we have taken to hanging all kinds of stuff off of our ARs. Lights, night vision, ir illuminators, lasers, bipods, not to mention high magnification tacticool near 3 lb scopes. For me, heavy guns have become safe queens, and “only lightweight accurate guns are interesting.” So we want reliability, accuracy, and light weight. Beautiful, extended review of a beautiful gun with one glaring omission. Entirely missing one leg of the stool.

  7. Gear up as your favorite Delsin Rowe Vest. Slim Fit Leather Jackets brings this iconic jacket from animation to reality, especially for all the fans of this video game. Delsin Rowe is the main protagonist and playable character, a young Native-American man who later realizes he’s a Conduit with special powers.


Please enter your comment!
Please enter your name here