TFB Review: Ruger’s Free-Floating Handguard PC Carbine

    That is a Promag DRM-A12 drum magazine made for AR glock mag wells

    The Ruger PC Carbine has been out for a while. Pete wrote a review of the regular PC Carbine last year back in March. The PC Carbine has been well received as it has a retro Marlin Camp 9 rifle feel but updated for modern shooters. The traditional rifle ergonomics was a bit of a breath of fresh air amidst a cacophony of AR-style 9mm pistols and rifles. For people stuck in backwards states, the Ruger PC Carbine was a way for them to enjoy the fun of having a 9mm semi-auto carbine. Competitors in the USPSA PCC division have taken to the Ruger PC Carbine as a platform to build upon. However, something was lacking in the traditional-looking carbine. The minuscule handguard left you wanting something else. So Ruger came out with a free-floating handguard PC Carbine.

    Regular Ruger PC Carbine in all its glory.

    Free-Float All The Carbines

    The regular PC carbine is fine but having a free-float handguard would be nice. Voila, I give you the free float handguard PC Carbine.

    Nothing has changed on the back half of the gun. It is still the same as the plain PC Carbine. However, the free float handguard is not a simple bolt-on component. When you remove the handguards you can really see the difference.

    The regular handguard is held on with a single bolt. Whereas the free float handguard PC Carbine uses four screws to attach the handguard and an entirely new rear section.

    Due to the updated mounting block at the rear of the free float handguard PC Carbine, they changed the takedown lever.

    The new free-float handguard PC carbine barrel is the same as the regular PC Carbine. I removed the mounting block just to confirm this.

    Regular PC Carbine barrel on top. New free-float handguard PC Carbine barrel below.

    The one thing that is a little bit disappointing is the position of the free float handguard on the PC Carbine. The handguard is offset to the barrel. See the photo below.


    3/4 view of the free floant handguard PC Carbine

    I would have preferred the barrel to be centered in the handguard but then the free float handguard would sit even higher and would look odd with the receiver. It would also bury the factory iron sights.

    One issue with having the handguard off-center is that the barrel now sits too close to the top of the handguard. There are M-LOK slots on top but you need to be careful which M-LOK accessories you use at 12 o’clock as the M-LOK screws might be too long and touch the barrel thus negating the benefits of the free-floating handguard.

    Mounting Optics To The Free Float Handguard PC Carbine

    I ended up using a Maxim Defense MRAX rail on the free float handguard PC Carbine since the mounting hardware is low profile. Rather than a bolt and T-nut, Maxim Defense inverted the MLOK hardware using a T-Bolt and nut on top. Since the barrel sits so close to the handguard the T-bolt hits the barrel before it can clear the handguard and spin into place. So I had to remove the handguard to install the MRAX rail.

    See how there are no screws protruding further into the handguard?

    Due to the MRAX Rail design, the rail sits too high and blocks the factory irons.

    Here is a test I did using the MRAX rail mounted to the free float handguard.

    Normally I do not like to mount optics to rails especially M-LOK rails. Someone at Magpul told me M-LOK was never designed to be a mounting option for optics. However, this MRAX rail is long enough and has enough mounting points that it is very stable. The uncontrollable variable would be any slop or flex in the free-floating handguard.

    If you recall my original PC Carbine had a custom optic mount that my friend Brian Miller made for me. It allowed me to mount a mini red dot sight to the barrel and it co-witnessed with the factory irons.

    @BKMILLER Ruger PC Carbine co-witnessing optic mount

    The irons co-witness with this optic.

    I prefer this setup since the optic is hard mounted to the barrel itself. The chances of this setup losing zero are a lot less than mounting an optic to a free-float handguard. Sadly I cannot use this mount on the free float handguard PC carbine. The optic mount is too low and sticks out too far. The handguard gets in the way of this. So unless I cut away parts of the free float handguard, I have to mount my optic to the handguard. Yes, I know there is a perfectly fine Picatinny rail milled into the receiver. However, I do not trust the barrel to hold zero every time I remove and reattach the takedown barrel.

    Competing With The Free Float Handguard PC Carbine

    Last June I went to a USPSA match and used the free float handguard PC Carbine in PCC division. It did well except the second to last stage.


    Murphy’s Law Rears Its Ugly Head

    As I mentioned earlier, the PC Carbine ran great other than my own floundering around and causing malfunctions like failure to feed issues. However, on the second to last stage of the match, I experienced an out of battery (OOB) detonation which was then immediately followed by the barrel separating from the receiver automatically. The IG video below has three separate videos, you will need to swipe to see each individual video. The first one is the entire stage from start to OOB detonation. The second video is just the OOB detonation. Then the third video is the aftermath.


    I was more shocked at the OOB detonation than anything else. Nothing catastrophic happened. It almost felt like an OOB in a .22LR. I felt gas hit my support arm and that was it. Here is what I think happened. The PC Carbine barrel has a knurled ring that you should tighten to get a good barrel to receiver fit. I did not check to see if it was tightened prior to this match. Due to how I grasp the handguard with my support hand I think I was adding a little bit of torque to the barrel. And while I was shooting the vibration moved the takedown lever just enough to unlock the barrel and allow me to twist it. Try the following at home (unloaded of course). Without moving the bolt, unlock the takedown lever and twist the barrel. It will move just a little bit but the bolt prevents the barrel from completely twisting and unlocking. So now you have a barrel that is partially unlocked but the round is still mostly chambered. Since the round is held in the bolt by the extractor the firing pin will touch the primer and now you also have a partially unsupported chamber. If you fired the PC Carbine like this then the bolt will move backwards due to blowback pressure thus completely allowing the barrel to freely spin and unlock in your hands.

    Take a look at the photos below.

    This is what the casing looked like after the barrel separated from the receiver.

    You can see how the casing is unsupported along the right and left sides of the case. Obviously, this is not the case when the barrel is tightened and installed properly. However, there was no catastrophic damage to the receiver or the barrel. See the chamber above? That is almost 1.75 inches long and it is recessed inside a giant steel receiver.

    I popped the casing out to inspect the barrel and make sure there wasn’t a squib.

    Looking at the receiver and barrel, I did not see any obvious issues.

    I reassembled the gun and test fired it to see if everything was fine. It passed and I shot the last stage.

    For due diligence, Pete and I notified Ruger and showed them the photos and video. Their engineers were curious about the malfunctions and asked to return the gun so they can inspect this PC Carbine and replicate the malfunction. After a couple weeks they returned the free float handguard PC Carbine. The fact that this gun did not explode in my face is proof that it is robust and overly built. The receiver is a massive block of steel and I think that is partially why it contained most of the OOB detonation.


    No, You Cannot Buy The Handguard Separately

    A lot of people have asked me this on Facebook and Instagram and as far as I can tell Ruger is not making the handguard available to those with the regular PC Carbine. However, there are aftermarket options. Midwest Industries makes a free-float handguard for the PC Carbine.

    It is not as long as the factory Ruger free-float handguard but it is slimmer and smoother to the touch. The Ruger free-float handguard has some rather abrupt corners. It is not necessarily uncomfortable but the Midwest Industries (MI) handguard is more pleasant to hold and it feels lighter. Unfortunately, the same problem exists for the MI handguard as the factory Ruger handguard. It is still offset and it blocks the use of Brian Miller’s optic mount. Also, the MI handguard is only held on with a single screw whereas the Ruger one has an entire mounting block and four screws.

    Final Thoughts

    The free float handguard PC Carbine is only $80 more than the regular PC Carbine. This is based upon the MSRP price. The handguard is not perfect but it is a better option than the regular PC Carbine if you want to attach various accessories.  The regular PC Carbine handguard only has a short Picatinny rail on the bottom of the handguard. Also C-clamping the barrel is tough since half of it is exposed. The free-float handguard and even the MI handguard provide better control of the barrel when moving and shooting.

    There is one cool thing about the free float PC Carbine and that is its uncanny resemblance to a PPSH-41. Especially when you add the shorter Promag Industries AR Glock drum magazine.

    I wish Ruger would make a laminate stock for the PC Carbine to really make it look like a PPSH. Or Magpul comes out with an X-series style stock. I guess I will have to settle for the CROM USA chassis in the meantime. If you do not have a Ruger PC Carbine take a look at the free float handguard version before making a decision. Check out Ruger’s website for more information.

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    Nicholas C

    Steadicam Gun Operator
    Night Vision & Thermal Aficionado
    Flashlight/Laser Enthusiast
    USPSA competitor

    Any questions please email him at [email protected]