NEW SF-308 Patrol Battle Rifle from Adams Arms

Adams Arms is adding a .308 model to their “Small Frame” lineup: The Patrol Battle Rifle (PBR).

An upgraded version of the small frame short-stroke piston AR-style rifle, this model includes the Samson Extended Evolution Rail, Magpul K2 Grip, and an enhanced sopmod-style buttstock. Over 50% of the rifle is reciprocal to standard AR-15 parts and accessories, making this a compact, reliable, and lightweight package with added rail space and options.


BARREL: 16 Inches
OA LENGTH: 33.75 inches
WEIGHT: 8.15 pounds
STOCK: Collapsible
SIGHTS: Optional
FINISH: Hardcoat anodized black
MSRP: $1,775.67

They are using Voodoo Innovations Melonited Barrels and offering “Guaranteed Accuracy for Life” which is pretty amazing.  I’d like to find out what the numbers are for their accuracy measure (and what “life” is), and at what point they will replace the barrel (I think I’ve seen the barrels offered in the $250-$300 range?).  That could be a pretty good deal if you shoot a ton.  Does anyone here have experience with Adams Arms (or the Voodoo barrels)?

You can find more information and see more pictures at:

Tom is a former Navy Corpsman that spent some time bumbling around the deserts of Iraq with a Marine Recon unit, kicking in tent flaps and harassing sheep. Prior to that he was a paramedic somewhere in DFW, also doing some Executive Protection work between shifts. Now that those exciting days are behind him, he has embraced his inner “Warrior Hippie” and assaults 14er in his sandals and beard, or engages in rucking adventure challenges while consuming craft beer. To fund these adventures, he writes medical software and builds websites and mobile apps. His latest venture is as one of the founders of; a search engine for all things gun related. He hopes that his posts will help you find solid gear that will survive whatever you can throw at it–he is known (in certain circles) for his curse…ahem, ability…to find the breaking point of anything.


  • Vitor Roma

    That is one slick 308 gun.

    • Herr Wolf

      Nice, but I like the looks of the CMMG MK3 a little more.

      • DIR911911 .

        i like the look of the already paid for dpms in my closet 🙂

        • Herr Wolf

          Yeah- I tried out a DPMS before I bought my MK3 🙂

  • TechnoTriticale

    What pattern magazine does it take?

    I wasn’t able to find anything on their site about that, and a prospective buyer is apt to have it near the top of the list of questions.

    • Looks like standard SR-25 type magazines. Publicity photos have shown them with Lancer L7AWM and Magpul PMAG 20LR.

      • TechnoTriticale

        re: Looks like standard SR-25 type magazines.

        That would have been my bet, but it’s odd that they’ve neglected to say, and don’t even appear to sell mags for it on their site.

        The word “standard” is iffy to use in the context of AR-10 style rifles. Heck, the Armalite AR-10, AR-10B and AR-10A all use different mags, and others have used FAL.

        • ostiariusalpha

          Yeah, but that’s falling by the wayside; the .308 AR is consolidating around the SR-25/LR-308 magazine.

  • G0rdon_Fr33man

    Where can I read more objective information about melonited barrels?

  • MoPhil

    I am still waiting for an XLP conversion kit in .308 Win., like Adams Arms offers for AR-15-type rifles. I really would like to built a piston driven AR-10 by myself.

  • Andrew Hobby

    I have an adams arms ar-15 midlength rifle, and I’ve been extremely happy with it.

    I gotta say, once you shoot a piston AR and don’t have to clean the bejesus out of the thing afterwards, its very easy to appreciate them. I’m definitely a convert now.

  • Nathan

    I can tell you i have two melonited barrels one being an adam arms piston upper. Excellent accuracey and the corrosion resistance is definitely there. The only chrome barrel that competes is daniel defense although im sure FN or a real custom manufacturer can. But the thing about melonite is that it is pretty easy to do and is cost effective as more start to use it. To me its the way to go although a good chrome barrel still is pretty equal to it.

  • Dracon1201

    I had one of the Voodoo barrels in an Adams Arms doss upper. Good stuff.

    I might be in for one.

  • notalima

    “Does anyone here have experience with Adams Arms (or the Voodoo barrels)?”

    I’ve owned several AA full uppers, and assembled a handful of AA piston kits (when they have the ‘free Voodoo BBL’ promotions). My oldest has several K’s of rounds through it and still runs like a top. I’ve been very pleased with out of the box accuracy, and long-term durability thus far. In fact, I just put together another upper from a kit over this last weekend (which had been on back-order from Black Friday 2014 waiting on the ultra-light weight BBL).

    I am very much looking forward to seeing how these pan out, and, more salient to my life, getting some .308 pistol conversion kits on the market. I’ll be on board to build a new .308 upper once those begin to flow.

  • Rusty Shackleford

    I’d like to see a long-term test of the SF-308 vs ARAK-31.

  • FedUpTxn

    Yes, it has been around a long time and it is NOT a lining. Instead the surface characteristics of the actual barrel metal is changed so it can’t flake off.

  • ThomasD

    Maybe it’s the angle of the photo, but does that pistol grip look a tad bit more vertical than usual?

    • notalima

      It is the Magpul K2 grip. More vertical by design.

  • BrandonR

    The Adams Arms Manufacturing plant is actually 20 minutes from my house. I’ve tested some of their full auto stuff at an event at my LGS and it runs really smooth. Stays cool too, probably due to the piston system. Been waiting to see an actual test on the accuracy of their newer stuff.

  • JQPub

    I’m still ticked at them for the fudge up with their 300 Blk pistol (can’t adjust the XLP gas block without taking off the FF Evo rail). But have only ever heard good things about them and this does look to be a contender in the .308 ‘battle rifle’ category.

    • Justin Hamm

      I’ve had one XLP gas regulator shoot out of the gas block ( I think it went into orbit) and the second one gets dirty in 50 rounds and cannot be adjusted without pliers. They kind of went a step backwards in this design IMO.

  • Adam aka eddie d.

    I like what Adams Arms (and sister brands) does product-wise,
    but I can’t wrap my head around the fact that they never write a full specs list
    to their products.
    You go to their site, check the descriptions, and half of the important information is always missing. How are you supposed to know the exact specs, compatibility etc. , if the mfr. is lazy to write at least a decent product description?
    For example: how can you write a piston kit description without
    mentioning how many positions the piston has, or what size gas port it requires on the barrel, or the weight of the kit? All fundamental information.
    I know Adams A. is not the only company guilty in this, but it’s still damn annoying.

    To put things into perspective: DPMS for instance spent two years with bombarding everyone with the specs of their new G2 rifles. Infographics, videos, parts displays at SHOT ’14 and ’15, even a separate website. I don’t have a G2, but even I know roughly what features the platform has.
    That’s the proper way of handling specs, not having people dig up forums and articles for the features of a product.

    • Justin Hamm

      This is their biggest issue IMO. Can’t really get a hold of them in a timely manner, and their website and the lack of info therein is poor at best. Even the pictures are of poor quality. It’s like the business side has yet to catch up with the engineering side.

  • Justin Hamm

    “Does anyone here have experience with Adams Arms (or the Voodoo barrels)?”

    I’ve done 20+ builds with AA parts and Voodoo barrels of different contours and lengths. They, along with JP Enterprises barrels are part of my go to recipe when building an AR15.

    I’ve come to expect sub MOA at 100 yards from these barrels and gas systems, along with a good trigger ( Geissele, Wilson, etc…). I mainly use Voodoo’s 14.5″ and 16″ med contour, mid length gas barrels and can obtain the previously mentioned level of accuracy with decent ( not match grade ) ammo at a fairly quick shooting pace. It’s become so standard in my builds and testing that if a barrel won’t perform to this level, I consider it to have an issue and will put it aside for later t/s’ing.

    I like that they can perform this well with 5.56 chambers as unless it’s requested, I don’t really like “match” chambers on what I consider to be an all around rifle. I want functionality and decent accuracy with nearly any manufactures ammo.

    Oh, and while these are 1/7 twist, I’ve never had one perform well with anything over 69 grains. I’ve shot tons of 75’s and 77’s out of these barrels and it’s obvious even at 100 yards that things aren’t right. This is typical for .22’s though. They all tend to be picky and honestly don’t really follow the rule of thumb that higher twist rates like heavier bullets. In my experience anyways….

    One rifle in particular that I just built and painted was under an inch in quick fire mode (minus the flyer which was my fault) with XM193! Granted, this rifle works very, very well, but still pretty representative of what I’ve found with their barrels.

    It had a Leupold 3×9 VX-R partrol mounted which while a great scope, has what I consider to be very thick reticle lines which cover the 1″ squares at 100 yards. Pics hopefully included. I tend to shoot multiples of 5-6 shots rapidly to check for thermal movement from the barrels. So far, all but the lightest of the Voodoo barrels don’t seem to have issues from mag dumps in approx a minutes time. The barrels also don’t seem to get near as dirty as either stainless or chrome. A boresnake and some of Hornady’s one shot lube does the trick to getting a shiny bore.

    That all being said, I’ve had my share of issues as well. For example, some of the parts I’ve gotten in the past have had excess salts from the bath in the gas block/regulator assemblies. This necessitated soaking overnight and a lot of physical effort to separate the two. I’ve also had out of spec bolts and one 18″ rifle length, lightweight barrel that refuses to work properly.

    To sum up, I expect that with a decent trigger, this 308 will be an excellent addition to anyone’s arsenal. I own three POF 308’s which I love, but the gas system in the AA units is simpler to work on, easier to clean and was at one time cheaper to replace parts. If I wasn’t starting a home FFL/knife business, I’d own two already as two is one, one is none….

    • Adam aka eddie d.

      Justin, thanks a lot for this very detailed, awesome writeup!
      This comment is worth a ton for guys like me.
      I’m very interested in modern piston guns, especially well designed short stroke ARs, but it’s damn hard to find facts(!) on these systems on the net.
      (And, as we’ve already discussed, Adams Arms doesn’t make life easier with their site either. 🙂 )

      A question if you don’t mind:
      Have you built a gun with a MOE or other non-freefloat handguard perhaps?

      It’s obvious from what you wrote, that these guns shoot very well with freefloat handguards (and lighter weight ammo), so the facts bust the myth of op-rods and piston gas blocks hindering accuracy (granted they’re well made and installed properly).
      What I’m really interested in is what’s the realistic expectable accuracy of the Adams kit with the standard gas block, on a 16″ general purpose gun,
      within let’s say 300 yards.
      Would be great to read about this.

      Actually, wouldn’t you be willing to write an article about your experience with the Adams Arms stuff?

      Building 20 piston ARs is not your average home bubba’d level. 🙂
      I’m sure the guys here at TFB would post the article, and it would be very useful.

      • Justin Hamm

        Adam, it would be my pleasure to share my experience with AA products.

        As a qualifier for why I felt I was able to respond to this article and
        give opinions is that over the last couple years I’ve spent probably
        close to six figures buying and trying different rifle systems and
        pistols in order to not only learn, but discern what I thought would be
        best suited to whatever situation I might be involved in. That’s in no way a boast. Trust me, my wife sure isn’t impressed with my awesome gun knowledge and how I gained it. LOL.

        The reality is, the gun rags are bought and paid for and most of us seem to know it. While the blogs are better, nothing beats first hand experience. Frankly, I’m pretty lucky to have the means to do this and I have learned a lot.

        My main criteria for the rifles is they had to be reliable first, accurate, easy to work on and ergonomic.

        I’m not here to debate DI vs Piston. Or AK vs AR. I’ve had lots of both and have come to conclusions that work for me in my situation.

        As to the expected accuracy, well, I built a rifle based on a matched Mega Arms set, JP Ent. 18″ barrel and matched bolt as well as a host of other high end parts and of course a crisp trigger from Wilson Combat. Even with the AA system and rifle length op rod, it would do 3/8″ groups at 100 with factory match ammo. I would suspect a real good shooter along with some home brew rounds would get them all in the same hole.

        Sub MOA, at least at 100 yards is the norm for the Voodoo barreled setups with the med contour barrels and free float rails. It’ll go out to slightly over 1″, usually around 1.5″ with a non free float setup like with a Magpul rail system. As usual, changing barrel harmonics messes with the ability to launch the bullet consistently. I’ve seen 1 MOA out to 300 yards, but I just haven’t had time to go out further than that.

        Honestly, being that the 5.56/.223 isn’t that great a cartridge or bullet design, and that I’m running 5.56 chambers, I’m completely satisfied.

        While anything touching the barrel and then resting whatever is touching the barrel on something like a sandbag will affect accuracy negatively, the operation of the gas block and op rod don’t. At least not that I’ve seen.

        The pencil barrels seem to be a little worse, but that seems to be typical for the thinner barrels. Which is fine, as in nearly all situations, the rifle is carried more than it’s shot and as such, lighter is better.

        The two best rails I’ve used are the Sampson’s like AA uses, and the Fortis Rev’s. The Fortis is the better of the two as it simply clamps on to the stock barrel nut, yet has room for AA’s newest XLP gas block to fit inside. However this does make adjusting the regulator difficult, which is why I use the mid length cut out Fortis rails. The Sampson uses a proprietary two piece spacer/sleeve thingy that goes over the stock nut. It can be a pain to deal with sometimes but does work. It also seems to allow for movement that can’t be tightened out of it.

        I try to build all my rifles to work in any situation. As such, I attempt to build them with as little internal friction as possible. That’s one of reasons I like the nitrided AA bolt carriers. I also have found the WMD uppers with their Nickel boron coating to help. Those along with PWS billet buffer tubes really make the system run smoothly. Add a Spikes T2 buffer and a JP Enterprises buffer/action spring and you’ll have a smooth running system. I also add a POF roller cam on my more expensive builds.

        On another note, on some of my AA builds, and factory AA builds the cam has worn a grove into the upper. This is a timing issue, possibly contributed to by the spring that is used to keep the bolt forward being too light. Some of the AA rifles do this and some don’t. Haven’t seen it be an issue and it stops after a hundred rounds or so. It has been acknowledged by AA, but they don’t seem worried about it.

        As an OCD kind of person, It bugs me, but it hasn’t caused a function issue in any of the many rifles I’ve had with this system.

        One important thing to remember is insuring the op rod moves as smoothly as possible. It will work with a surprising amount of resistance, but the key to smooth operation is to get the rod, the barrel nut torqued and aligned and the gas block over the gas port so that it not only moves back and forth but spins easily between your fingers.

        I have on occasion run into the rail on the gas block not being aligned with either the upper rail or forearm rail but aligned in all other ways (centered over the gas port, free movement of the op rod). This can cause the BUIS front site to not be aligned with the rear, which is a no go IMO. This is why I actually like the non railed gas blocks as it forces you to utilize a railed forearm for the front site BUIS. However, any movement in the rail, such as I’ve experienced with the Sampson’s, negates the ability to get your BUIS aligned. That’s why the Fortis is the better of the two. Once torqued, it’s tight and straight.

        My rifles can run upwards of $2500 before optics and everything has to align and work properly. I did enough time with various AK’s and Sigs for that matter with canted gas block/sights. Bugs the sh*t out of me.

        Btw, Magpul’s inexpensive forearm setup, while both cheap and durable, can actually cause more issues with parts rubbing. If you don’t have both halves locked perfectly in the Delta ring and the retainer spring, clip combo, you may affect function with lighter loads. In some cases the upper forearm half may rub. Running full 5.56 rounds you probably won’t see or feel it, but you will with lower powered .223 rounds, or some of the cheap/Russian stuff out there.

        Hopefully I answered some questions without getting too carried away. If anyone has more questions, perhaps emails or some other venue would be better? I can way, way deeper on just picking a decent receiver set and why and I also have a ton of pics of most of the builds and target shots as well.


  • Justin Hamm

    Way better in durability and for accuracy. Supposedly allows greater fps in velocity as well, though I’ve yet to test those claims.