PCP Polymer-Cased Ammo Review

The folks at Lukcygunner have reviewed the new PCP Polymer-Cased .308 Win. ammunition. The idiom “Damned by faint praise” comes to mind. The company is marketing this as a premium brand and it needs to shoot like a premium brand. Civilians are less concerned about ammunition weight than the military. On the other hand a Remington VTR (in its much criticized factory stock) is probably getting 1.5 MOA at best anyway. Accuracy comparison should be done with either a more accurate stock rifle or an accurized rifle (getting off topic here but a Remington 700 can easily be made more accurate by the addition of an HS-Precision stock and Timney trigger. Total upgrade cost about $550). Chris’ video review is embedded below …

What I find especially interesting is the lower chamber temperature. I am not sure how they are achieving this. Older polymer case ammunition historically left the chambers to hot and at risk of cook-offs.

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.


  • guest

    CCI makes some .357 ammo with aluminium cases (however, with berdan primers that do not reload easy).
    I have no idea as how good this is vs. steel, brass, plastic etc but they do seem to work and the cases themselves are ridiculously light.

    • scw

      Strangely aluminium case has used on the M230 chain gun on the AH64 for a long time but on one seems to have used aluminium case on small arms.

      • Bob Barker

        Perhaps because aluminum is not GI proof enough? I assume the M230 is a closed ammunition system once the belt gets hooked by a “trained professional”, no real chance for the casing to get damaged.

        • Alex Nicolin

          One problem with aluminum is that, while the metal itself is soft and malleable, the oxide is one of the hardest substances in nature. If cases become scratched and oxidized, the dust will polish, and eventually wear off the chamber. That’s why aluminum cases are lacquered.

          The other is that it is actually to soft to contain high pressures. That’s why they make only low-pressure ammo cases for it. Most handgun rounds run below 40KPSI, while rifle rounds hit 60KPSI. The chamber pressure for 30×113 mm ammo is ~45KPSI http://www.ordtech-industries.com/2products/Ammunition/Medium/30×113.html

          • Aluminum cases are also standard for the 30x173mm rounds used in the GAU-8. 30x173mm rounds run over 50 KPSI.

            The major issue for aluminum cases is the danger of burn-through resulting from internal flaws in the case. It will surely ruin the chamber.

    • Kivaari

      The aluminum CCI Blazer ammo has seen failures that ruined guns. I inspected a S&W revolver where the Blazer case split. Melted aluminum, flowed toward the recoil plate, cutting into the steel of the cylinder. It ruined the cylinder.
      In H&K M94 and MP5 the aluminum cases would not extract or eject reliably. It did produce higher velocity with less deviation between shots. I was asked to send 2 boxes of the ammo to CCI for testing. They blew me off, saying the ammo was fine. Obviously the folks in Lewiston only did tests checking for velocity. pressure and standard deviation. They sure couldn’t understand that it was unsuitable for the fluted chambers of H&K guns. Now 30 years later, I’m still ticked off.
      They never did replace the ammo or the shipping. They did pay for S&W to repair the revolver.

  • Andrew


    • Bob Barker

      Polymer cased ammunition is an important area of research for the military. Ammo is heavy, ounces are pounds, etc etc.

      • BryanS

        Pounds are lost MPG… and billions of payments from worn out soldiers at the VA.

        I wonder what these guys will look like in 30 years from now with all that equipment they are hoofing around?

    • Anders Albertsson

      Until it’s cheaper than brass and more accurate than steel, I agree. The weight savings is not worth $2 a round, at least for anyone who pays for their own ammo.

    • wetcorps

      Well it’s a beginning. They or another compagny might be able to make polymer cased ammo viable in the future.

  • Lance

    Id stay with brass saw how 5.56mm polymer case work do NOT like them there not reliable.

  • Thomaspayne

    PCP is better off making injection molded polymer lady toys if they think I’m gonna drop a $2 bill on a single round of ammo.

    • LectricChair

      PCP is an appropriate name for such a company, as you would have to be smoking angel dust to even think about paying that much for ammo.

      • JT

        Wrong. Those zombie circus clowns are wily ****ers

        • JT

          You need all the ammo you can carry to deal with them

  • Tommy Huynh

    “Older polymer case ammunition historically left the chambers to hot and at risk of cook-offs” – Wrong. The Author is confusing several things here. First, polymer cased ammo has always resulted in lower chamber temps due to polymer’s lower thermal conductivity. Cook-offs were a problem with caseless ammunition since the lack of a thermal barrier (the case) resulted in greater heat transfer to the chamber. When the next caseless round was chambered it experienced the same increased thermal flux (in the opposite direction) and there were cook-offs.

    • Ben 10

      sounds like plastic casings are the wave of the future. would certainly save on brass. lower chamber temps is always a good thing.

    • David

      So where does the heat go? I’m not asking sarcastically.

      The too hot to touch brass ejected from a firearm is heat literally being extracted from that system. The experiments I’ve seen with previous polymer ammunition was that chamber temps were actually lower with brass because of how much heat is physically ejected from the chamber in the form of brass/steel.

      What you say makes perfect sense in that polymer is a much better insulator than brass, but it’s not like less heat is being generated per shot, so the heat has to go somewhere, I’m guessing the first couple of inches of barrel. This can easily radiate to the chamber.

      My guess is that they’re marketing this as premium ammunition for the likes of target shooters and hunters who don’t really worry about heat affecting reliability.

      • gunslinger

        i would agree that the heat would be transferred to the first few inches of the barrel. if the case doesn’t “absorb” it and eject it, i would guess there is a bit higher temp as the round fires.

      • Paul Epstein

        Your argument seems logical, but it’s neglecting the largest conductor of heat and the hottest material leaving the barrel- the combustion gases.

        Which, incidentally, are the source of the heat. Anything that prevents them from conducting heat into the gun means more heat leaves with them. The fact that the outside of the brass case is hot means it’s transferring heat to the chamber, the inside of a polymer case will be even hotter than brass but that heat will stay on the inside where it belongs.

      • Tommy Huynh

        The brass is hot because it is being directly convected onto by burning powder at +2,000F and +40,000psi. Not because it is in contact with a chamber that doesn’t even exceed 150F ofter 200rds if continuous fire (the barrel, gas block, gas tube etc.. is where most of the heat ends up). If what you were saying were true, brass would not be hot enough to burn you on the first few rounds where the chamber is cold, but anyone who has done any amount of shooting knows this isn’t true.

        The heat does have to go somewhere. Down the bore and into atmosphere is where most of it goes. That delta in heat energy is insignificant compared to the total amount of heat generated though. And BTW, heat does not easily radiate from barrel to chamber. It would mostly be *conducted* (Thermo 101: Heat transfer occurs through conduction, convection, or radiation) but even then steel has relatively low thermal conductivity. That is why if you look at the barrel in a thermal imager you see huge temp gradients where the first few inches of the barrel can be hundreds of degrees hotter than the chamber which is just a few inches away.

  • Ben 10

    maybe this stuff would be cheaper if it were limited to power pressure pistol ammo,.

    • Ben 10

      ahem, i mean lower presure pistol ammo.

  • KC

    I’m confident the $2 a round price tag is for their limited “beta” run of ammo. Initial runs of anything cost significantly more than you’d expect and I anticipate PCP is actually currently losing money until (at least) they sell their first mass-produced run.

  • SeanSorrentino

    Why would anyone buy a gun stock from a company that hired Lon Horiuchi as a spokesman?

    • Steve (TFB Editor)

      They did?

      • SeanSorrentino

        Umm, yes. Are you the only person in the firearms blogging/writing industry that doesn’t know this?

        Google HS Precision and Lon Horiuchi. There’s plenty there to let you know about it. Not only were they stupid enough to pay for a testimonial from the Ruby Ridge sniper who killed Vicki Weaver, they screwed up their attempt at damage control.

        I wouldn’t buy a damn thing from HS Precision.

        • Steve (TFB Editor)

          I misread your comment, wondering why PCP would have hired them. By contra to public perception, I don’t know everything … being human sucks.

          • Jeff Allen

            Thank you for being unbiased. Many companies have made mistakes. Many of them have changed ownership since those mistakes. To boycott them all gets to be a little foolish after awhile. Who am I going to buy my guns from if I have boycotted them all???

    • Jeff Allen

      If you drive or ever ridding in a Ford you are no different. Ford Pintos with their gas tanks killing people and they knew it would back in the 70’s. Just saying. Lon Horiuchi was a long time ago. Im sadden for the lost of life that happened on that terrible day on Ruby Ridge, but this constant bashing of HS for hiring 1 guy that murdered 1 person when so many companies have killed so many more. Chevrolet just got busted for not recalling a car that has killed 13 so far. If we are to boycott every company that has killed a person, your not going to be buying much…

    • Jeff Allen

      I’m not excusing HS for what they did or even Troy Industries who hired
      Lon’s partner last year as an instructor. I’m not going to be trowing
      my HS precision stock in the trash either.

  • Tom Nichols

    Never ceases to amaze me the volume of discussions about rifle “accuracy”. The steadiness (or lack thereof) of the shooter will account for probably 99.999% of the variation between shots – assuming no wind. A rifle would have to be securely held in a heavy vice or other fixture and fired indoors to really determine how much MOA drift is due to variations in the mechanism itself.

    And really, the only people who should even care about this stuff are the serious match competitors.

    • shaw08

      Truth brother. As I said in another comment, there is no ammo of high enough “quality” to make a cheap rifle shoot like an expensive one, atleast not from the factory. If you want to push your rifle to the max of its capabilities you’d be much better suited buying a small reloading set up and working up your own loads at about 1/4 of the cost. With this stuff being $2/rnd you could buy a press and all the other things you need, and make 200rnds for about the same price as 200 of these. While we all like accurate and quality rifles, that part of the market is starting to get a little crowded these days. All people want is safe, cheap, and consistant. Most people wont ever shoot past 300yds, and if they are its either at a target or at an animal. Niether merit the price of this ammo IMO.

  • wyomingsomeday

    Alright, this is the third post by TFB that I’ve seen in the past five minutes mixing up “to” and “too.” Blog writers who are trying to present information through written word need to understand basic English grammar.

  • Vitor

    Well, Im just glad it actually worked without issues, specially in the M1.

  • ColaBox

    Promising but too expensive.

  • j

    Honestly, I just really don’t like plastic.

  • Kivaari

    Don’t forget that the brass cartridge case is heated by friction. As it expands to seal the chamber the disruption to the bond between atoms creates heat. Remember when you bent a piece of wire to break it, it gets hot. The cases do the stretching fast. A G3 chamber allows quite a bit of expansion, therefor friction heat is generated.

    • shaw08

      The issue with heat has been solved with the design they released as opposed to earlier models. The controversy over heat when experimenting with new cases has mostly been talked about when they experimented with aluminum cases because illuminum transfers heat really efficiently, unlike brass and polymer that retain a significant portion of that heat. Since the transfer of heat was so high with illuminum it left the chamber temperature so high that rounds were likely to cook off after only firing 200rnds. With polymer on the other hand the issue has been that polymer is such a good insulator that it retains so much heat that it melts(also having lower melting temperatures doesnt help). The design they released uses a metalic case mouth and base cup, these being the areas where the most mechanical energy occurs it seems too much for a pure polymer case to hold up to.

      Personally I like brass casings, but if they were able to make a polymer casing that could be reloaded, and was cheaper than brass then it would make sense. But given that this stuff isnt gonna be below $1/rnd anytime soon i dont see this going well. No amount of “quality” in the production process of this ammo will make a moderately accurate rifle anymore accurate. A perfect example of which was shown in the video. The Rem700VTR is usually about a 1.5MOA gun, and even putting $2 ammo in it doesnt make it any better. If you can already buy high quality ammo for $1/rnd or $1.50/rnd why would you want to pay extra? I believe this is a very poor marketing scheme for PCP and when they want to corner the market with their product they will lower the price to a more reasonable selling point and mass produce. The High End niche of the firearms market is already pretty crowded, how about giving people what they want for a change.