6.5mm “Patriot Combat Cartridge”

Forming the 6.5 Patriot Combat Cartridge (PCC) from virgin brass. Image is from rifleshooter.com

One thing I have not yet gotten into is reloading, and I know very little about the manufacture of such things. I mean, I know how a round is constructed, but doing it, and further, innovating, is beyond my current skill set. I find things like fire forming and case trimming both fascinating and a little dangerous.

Shout out to Bill for pointing us to this article discussing an interesting way (created by Illirian Engineering and Design) for adapting a standard .223 Rem casing to accommodate a 6.5mm projectile: http://rifleshooter.com/2014/11/6-5-patriot-combat-cartridge-6-5-pcc-6-5mm-wildcat-for-the-ar15m-16/

Since it utilizes a 223 parent case and only requires the change of barrel and magazine in a standard AR-15/M16, you can use the rest of your setup, and presumably your shooting mechanics will remain the same.

And no, I’m not going to include this in the weekly ammo prices… 🙂

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 IronSights.com; 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.


  • gunslinger

    but what about that new 5.7 ammo posted?

  • noob

    hmm so this is like the magazine compatibility of blackout with the projectiles from grendel?

    • Roy

      Yup, trade off is some velocity from loss of powder capacity.

      If you’re that into swapping calibers with only barrel swaps, there’s also the .277 Wolverine from MDWS that’s catching it’s own following, even with factory ammo online already, priced pretty reasonably even (so arguably passing up the 6.5 PCC with that reasoning). It’s running about 100 fps slower than the 6.8 for similar weight projectiles, but you get to run 30 round mags.

      • noob

        I’m confused at what 6.5mm does relative to 6.8mm. is 6.5 better for high speed long range? if so would robbing some initial velocity in the 6.5mm patriot be not so bad because it retains its velocity downrange due to good bc from the longer skinnier bullet (same start slow end fast philosophy for grendel, only with less initial velocity)?

  • Christian Hedegaard-Schou

    It’s not going to be a cartridge capable of any decent accuracy/precision due to the really short case neck. I’d be genuinely surprise if you could make 1 MOA with this.

    • Steve Truffer

      When the round was in development, many people reported good accuracy after the throat was revised. 1-1.5 MOA

  • Don Ward

    Needs 1.12 more millimeters of FREEDOM.

  • Steve Truffer

    It has less case capacity than the Grendel, but that works to make it more efficient with what powder it does have. The Grendel truly shines out of a 24″ barrel, where as the PCC seems to hit its sweet spot at around 18 inches (though longer barrels are made). After the 6″ barrel disparity & smaller case capacity, The PCC seems to get 1500-1600 FPE, compared to the Grendel’s 1600-1900.
    The 6.8 version has issues the the stabilizing ribs, and needs a Grendel/SPC follower.

    • This is really more about powder burn rate than case dimensions.

      • Steve Truffer

        Indeed. Smaller cases, with the same amount of powder = higher pressures. Nitrocellulose powders burn faster the higher the pressure they are under. This means that (to a point) a given powder will burn faster in a smaller case, if the charges are the same. If the powder is burning faster, then more force is exerted on the bullet with less barrel length (I hope that statement is comprehensible). This means that in our case, putting a 6.5 Grendel in an 18 inch barrel, and a 6.5 PCC in the same length, with identical loads (with bullet weights up to about 144 grains, beyond which belongs to the Grendel), the PCC is going to see a higher velocity.
        Fascinating Arfcom threads on the topic.

        • All of what you just said is true, but I more meant that most of this talk of “sweet spots” has more to do with the type of powder chosen than anything else.

          • Steve Truffer

            Ah. I guess I should revise that to “Most common loadings for the PCC hit their sweet spot”

  • Spidouz

    6.5PCC… 6.5 MPC, 6.5PPC, 6.5 Grendel, 6.5 Creedmoor, .260 Rem, .25-45 Sharps, .257 Roberts, 6.5×55… aren’t they pretty much all very similar in some ways?

    I’d prefer for manufacturers to pick one and stick to it and make it more popular and more affordable… Otherwise, it’s just gonna be just “one more exotic caliber”. To me, the 6.5 Grendel seems to be the more appropriate so far, and the .25-45 Sharps looks good on paper. I’m no ballistics and cartridge expert, but I think there’s no need to reinvent the wheel every day…

    The 7.62x54R and the .45ACP are cartridges created over 100 years and still perfectly good to be still in use today. I’m just saying…

    • About the only thing all those caliber have in common is that they have approximately the same diameter bullet.

      • Spidouz

        True, but they also don’t offer anything really new that hasn’t been done already. As mentioned already, the 6 to 7mm is known for being the sweet spot for medium and long range… fair enough.

        So, a tons of cartridges already exist for that matter… regarding if you want a long range, starting with the famous 6.5×55 and any other variant and similar cartridge. And if we really want a shorter OAL cartridge, the 6.5 Grendel already fits pretty well this spot, and the .25-45 Sharps (from what I read on paper) too.

        I personally don’t see any real value here, any reason to be excited about this 6.5 “Patriot” cartridge, mainly when so much cartridges already exist (for over 100 years for some) in this 6 to 7mm range.

        And it’s without saying anything about the “Patriot” name… I mean, c’mon, really?? Do you sincerely believe it would help its cause? Tomorrow, Russia would propose the russian version of the 6.5 Grendel for the AK-12 and they would name it: “6.5 Soviet Patriot”, we would all roll of the floor laughing. And it would surely not have as much success as the 7.62×39 has.

        To me, it just appears like another marketing thing and nothing else… sorry!

        My 2¢

  • Phil Elliott

    What was wrong with the old 7mm TCU? I’m getting about 1600 fps. with a 120 gr. in a 10″ bbbl.

  • You’d be very limited in pressure.

    • Blake

      Very true.

      While we’re at being purely theoretical here, if you feel like playing with Solidworks some more, any idea what the max pressure of a 6.8SPC case necked-down to .224 & & loaded with a 90gr bullet would look like? That case is significantly more stout than the older parent cartridges & still fits in the AR action…

  • Spidouz

    I shoot it often enough to know it, thank you. I’m not quite sure it’s still in service thought… still in use and production, that’s sure, but in service, I’m not sure (I should check). But that’s not the point.

    The point is that it’s a perfectly good cartridge and every day there’s no need for 10 new similar caliber to this 6.5×55, that don’t offer anything really new… beside being the “new thing”. And if we want a shorter OAL cartridge, the 6.5 Grendel fits perfectly this spot already. So again, no need for another 10 different cartridges every day, to me it’s just a marketing thing.

    It would be like saying: “Hey guys, we just invented the .45APC, “.45 Auto Patriot Cartridge”… which is 2/100th of a inch longer and 100 fps faster from the previous .45ACP”. To me, that would just be some marketing thing and I’d prefer to stick with the .45ACP.

    For some reason, the 6 to 7mm range is the sweet spot for medium to long range precision. And so many cartridges already do exist today. I don’t see anything valuable from this 6.5 “Patriot” that any other cartridge can’t do…

    Sometimes, the old good recipes are just the best one, just like for the .45ACP, the 7.62x54R, the 6.5×55, the 8×57, the 7.5×55, the 9mm, the .357 Mag, the .44 Mag, the .223, the 7.62×39, the .308 and the .22LR (just to name few).

    My 2¢

  • Dragonheart

    If you want to learn how to reload it’s easy and you don’t have to start out building wildcats. I have taught numerous friends how to reload in a very short period of time. Like anything there are do’s and don’t to learn that will keep it safe.

  • Phil Elliott

    Not sophisticated enough to extrapolate from 10″ to 20″ velocity wise, but I think it would be quite a bit more, probably close to the same velocity. Granted a 120 gr. 6.5 bullet is going to have a better B.C. than a 7mm. My case is still the same as yours, simple neck up from 5.56. Running mine in a T.C.