How do Rifle-Caliber Pistols Perform: Spike’s Tactical ST-15 vs Kel-Tec PLR16 vs Arsenal SAM7K

Oleg Volk has written a excellent series of articles comparing three pistol-variants of full sized rifles, each chambered in a different caliber and compared ballistic performance and handling characteristics. I highly recommend reading the series.

I originally dismissed them as loud, awkward, and ballistically compromised, but an opportunity to test them side-by-side was too good. My friends and I went to the range with one in each of the common calibers: PLR16 in .223, Spike’s ST15 in .300 BLK and Arsenal SAM7K in 7.62×39. Each of these guns has been customized a bit, so the test reflects non-stock configurations.

Besides the penetrating ability, .223 is also far easier to shoot at longer ranges. At 100 yards, a bullet from even a long-barreled .22 revolver would drop 17-18 inches, while .223 ball would only drop 3.5 inches. When aiming at small to medium game, this is a significant difference. In defensive use, the somewhat awkward handling of the larger pistols is compensated by the increased power and the ability to shoot one-handed.



Part 1 of the series can be read here at AllOutdoor.

Steve Johnson

Founder and Dictator-In-Chief of TFB. A passionate gun owner, a shooting enthusiast and totally tacti-uncool. Favorite first date location: any gun range. Steve can be contacted here.


  • Don Ward

    I doubt in a defensive situation that most people will be firing AR and AK pistols “one-handed”.

    I’m curious how the weapons fair in a 5.56 vs .357 Magnum or .44 Magnum duel. I’m pretty sure of the outcome of course.

    • Paul White

      I would love to be able to buy something semi-automatic in .357 magnum with about an 18″ barrel (to avoid NFA crap) and at least a 10 round capacity. I’d pay up to ~750 for that.

      • Don Ward

        Yep. Pretty much we’re constrained to lever guns (which you know I dig) for that sort of fun.

        • Bill

          Which isn’t all bad. I’ve played with them as utility/defensive/patrol rifles and other than being a little fragile, they can work.

          I also regret not picking up one of the Rossi pump guns in .357

      • Cal S.

        The challenge with .357 Magnum and .44 Magnum cartridges for semi-autos is two-fold:
        1) Cartridge geometry. They were both designed for revolvers, and hence are not rimless, leading to some feeding issues.
        2) Cartridge variance. Different loads lead to different head-spacing and different overall dimensions. Not an issue for tubular magazines in lever-action rifles or cylinders on revolvers, but obviously can lead to significant problems for vertical magazines.

        Conan Arms and Magnum Research found ways to do it, but their products are amazingly expensive. Generally speaking, that’s because the people who embrace .357 magnum don’t embrace semi-auto (like my dad, revolvers and levers all day long). There are other cartridges (.40 S&W & .357SIG, for example) that offer similar ballistics in a much more semi-auto friendly design.

        • Don Ward

          Ruger has (had?) a 44 magnum semi auto. Although I know zero-point-zero percent about it.

          • 1911a145acp

            RUGER made two versions of their 44 Magnum Carbine. 1st was made from ’61-’74, the second improved simplified version from’75-’85. Both expensive and hard to find now. Better suited for light duty hunting. Both had many cast parts and suffered from cracking rec. and reliability. Only held 5 rounds. Marlin 44 mag lever gun in 44 Magnum a better choice. Viable weapon platform with Irons, dot or low x scope. Using Cor-Bon or Buffalo Bore 44 Special +P you can fit 13 rounds in the rifles

          • Tassiebush

            They made a rotary magazine .44mag semi auto a few years back too. Called the deerfield carbine from memory. I yearned at pics of them from across the waters…

          • Sickshooter0

            Rem 44 Mag Carbine

        • RICH

          If you can find one of the old Ruger .44 MAG semi-auto rifles they functioned flawlessly ! They looked pretty much like the 10/22, were compact (carbine sized) and fed from a magazine….. they are fantastic !

          • Cal S.

            I have no doubt! That looks like a great firearm from a great company!

            But, doesn’t seem like there’s much demand these days.

      • 1911a145acp

        They call that a 9mm carbine firing 9mm +P+ ammo….

      • Bill

        M1 Carbine and JSP ammo…I haven’t compared ammo costs but I bet it’s pretty close

  • Tahoe

    Didn’t the ATF just rule that attaching a tube onto an AK pistol like that turns it into an SBR, not a pistol?

    • -V-

      For the AK’s it actually attaches under the rear grip, so no tube, no fuss. But yeah, that legal opinion is a bit odd. I question how well it would realistically stand up in court.

    • Guest

      Attaching, no. Absolutely not. Still 100% legal.

      Shouldering the arm brace, still 100% legal.

      Attaching “with intent to use a shoulder stock”, and the ATF will come after you… or so they’d like us all to believe.

      • RICH

        Shouldering an ‘arm brace’ is 100% ILLEGAL ! Read BATF&E’s response letter… it’s all over out here ! You best check it out….. unless you can do the 10 years and pay the $100,000.00 fine with no problem.

    • skusmc

      You’re probably thinking of the letter that TFB posted on here four days ago in which the BATFE said that attaching a tube by itself is a violation, but a tube with a Sig Brace is not.

  • Ethan

    A little off topic, but from what I’ve read the AR-15 pistol arm brace ‘issue’ stands as such:

    Attaching an Arm brace to bare buffer tube: Still 100% legal.

    Shouldering the arm brace: Still 100% legal.

    Attaching an Arm Brace to a bare buffer tube “with intent to use a shoulder stock”, and the ATF wants you to believe they will come after you…

    Do I have that right?

    • skusmc

      It’s hard to tell how the BATFE is interpreting law this week. I’ve heard when they read the NFA they get hopped up on peyote and use an ouija board to pick which parts to use.

      But according to Acting Chief Kingery in his letter TFB published in January, using the Sig Brace as a stock “redesigns” it as an SBR. Intent when you installed is irrelevent. IF you shoulder it, according to Kingery, you’ve redesigned it into an SBR. For an example, he alluded to the use of a nail gun as a weapon in that it would instantly reclassify it as an AOW.

      Would they win in court with their new magical definition of the word “redesign”? I have my doubts, but that’s their story. For now anyway.

      • RICH

        I had a very good friend of mine (a Chief Deputy for a Sheriffs Dept.) get jammed up by the BATF&E for having an old AR 15, SP-1 that would sometimes ‘double fire’ on him… due to worn parts. He was arrested and in the trial BATF&E produced a “TAPE” showing that the weapon could fire several rounds as a full automatic. He caught the disparity on the tape & mentioned it to his attorney….. the Feds left the time stamp on the video !!!
        When they asked the jury to watch it again and pay attention to the time….it took about 2 1/2 hours to go through a 30 round magazine !!! The case was immediately dismissed by the Judge ! When he went to pick up his guns they were so f’ed up he told the fed’s to keep them !…… True story, it was in the news papers…!

        • Ethan

          Link? I believe you I’d just like to read about it.

    • RICH

      Using the arm brace in any manner as a “Shoulder Stock” is “ILLEGAL” ! It is meant to be used as an “arm brace” … strapped to your arm…ONLY ! Pull up the letter from BATF&E and read it … a few times. It is quite explicit. A violation is punishable by, ‘up to 10 yrs. in prison and a fine up to $100,000.00’ Plus they will take every firearm / all ammunition you own ! !

      • Bill

        Could you cite the section of the US Code or CFRs you’d be charged under? The letter does state that it’s not legal, but there still has to be an actual regulation in place before charges can be filed, with all that drafting a regulation entails. Granted, It’s pointless in this case to try to argue for the use of something for which it wasn’t designed in a manner that’s pretty obvious is meant to circumvent SBR regulations.

        • Cymond

          I’m not going to look up the exact code number for you, but it would be the same code as building and/or possessing an unregistered SBR.

  • Will

    See guys? This is where you are all misguided.
    You are trying to attach logic and common sense to the BATFE.

  • Patriot Gunner

    If M855 goes the way of the dodo so will .223/5.56 and you better believe that next on the chopping block for the BATFE is 7.62×39. Good Lord we need to get rid of this “sporting” use nonsense.

    • Ethan

      Write. Call. Email. ACT! =)

      • Patriot Gunner

        Damn right brother! I would also encourage a donation to the NRA-ILA. Every bit helps.

    • RICH

      We need to get rid of all the friggin’ libtards that think any ‘gun by itself’ is EVIL !!
      They want to totally control every aspect of ‘free America’ ! ! !

    • Sam Schifo

      How exactly? The ATF already banned steel core x39 years ago. I don’t see how they could interpret any law to ban all standard x39.

      • Patriot Gunner

        Because any rifle cartridge will penetrate level 2 body armor. Its called the slippery slope my friend.

        • Cymond

          But the law doesn’t define AP pistol ammo as “whatever will penetrate level 2 body armor”. The law lists specific criteria for the materials & construction of the bullet. I know it often seems that ATF’s interpretation of the law is making new law, but they’re really just extreme stretches of the law as written.

          Completely redefining AP pistol ammo would take a genuine new law, not just a reinterpretation.

      • buzzman1

        Well the 115 – 120 gr bullet weight is below that of most pistol bullets so its obvious to an obama appointee that its meant to be shot as a pistol so it should be banned.

    • f.t.

      No, we need to get rid of this useless, worthless, gutless President we have.

  • Squirreltakular

    Was anyone else as surprised as I was when the whole rifle-pistol market took off a few years ago like it did?

  • guest


    With “arm braces”

    • 1911a145acp

      Hhhmm… just realized- BOTH my hands have “Arm braces”! I think I am illegal!

  • gunsandrockets

    Have you heard the latest? ATF just declared that using a handgun with both hands (such as weaver grip) ‘redesigns’ the handgun into an AOW.

    Just kidding!

  • El Duderino

    I’m still a bit surprised that no one has created an AR that uses Desert Eagle mags (and, of course, calibers). Just to do it, not because it’s amazingly practical. The bolt would have to be custom made, of course, but that’s not terribly difficult for a skilled machinist/gunsmith.

    Maybe it’s just because Deagle guys are too macho to admit they need a rifle to pair with their gigantic…handgun.