BSF Perforated Carbon Fiber Sleeved Barrels

There are several companies in the industry offering carbon fiber wrapped barrels. What makes BSF different is that their barrels are not carbon fiber wrapped, but they are carbon fiber sleeved or jacketed. Also, the carbon fiber sleeves of BSF barrels are perforated to aid cooling.

The difference is that in the case of wrapped barrels the carbon fiber actually hugs the barrel and touches it all along its length. In the case of BSF barrels, the sleeve of perforated carbon fiber touches the barrel only at four contact points: near the chamber area, before and after the gas block mounting portion and near the muzzle threads. The space between the barrel and sleeve allows air to flow through it and cool the barrel faster and more efficiently.

The carbon sleeve also works as an isolator and resists the heat transfer to the outside surface. As shown in the video below, the owner of the company grabs the barrel of the rifle after doing two mag dumps (60 rounds):

Actual base barrels are made of 416R stainless steel. The following chamberings are available for AR-15 barrels: .223 Wylde, .300 Blackout, 6.5mm Grendel and 6.8mm SPC. There are also BSF barrels chambered in .308 Winchester and 6.5mm Creedmoor for AR-10 pattern rifles.

BSF barrels are manufactured in the USA. They are available through Rainier Arms. Right now the .223 Wylde barrel with 1:8 twist rate is the only one listed on their website with a $569 price tag.

Here is also a video by Rainier Arms telling about these barrels

This company and their products are another proof of how small businesses drive the industry with the innovation they bring to the market and the passion they do it with.

Hrachya H

Being a lifelong firearms enthusiast, Hrachya always enjoys studying design, technology and history of guns and ammunition. His knowledge of Russian allows him to translate and make Russian/Soviet/Combloc small arms related information available for the English speaking audience.
Should you need to contact him, feel free to shoot him a message at


  • Rick O’Shay

    “The carbon sleeve also works as an isolator and resists the heat transfer to the outside surface.”
    I’m sorry, but this just sounds like an incredibly bad idea.

    • MrBrassporkchop

      I was going to say the same thing.

      The only situation I can see this useful is a hunting gun where you only need to take a few shots and the carbon fiber lightens things up.

      With targeted shooting heat would throw off your point of impact. It’s too expensive for plinking. You don’t want a barrel that can’t cool down in battle/tactical use.

      Looks neat though.

      EDIT: Just saw the weight, it’s like 1.8 pounds. Half a pound heavier than pencil profile barrels. Why the hell would anyone buy this thing?

      • Sgt. Stedenko

        Operators have to operate operationally.

    • marathag

      The sleeve acts as outside support that doesn’t retain heat as much. The inner barrel still dissipates heat via conduction to the air via the slots, so will cool better than standard carbon wrapped barrels, while retaining most of the stiffness.
      So light, allows cooling with less deforming than a pencil barrel.

      For it to be really effective, you would need a Lewis Gun style setup that draws air forward, drawn by the muzzle blast.

      But the main attraction is Tacticool.

      • LGonDISQUS

        Yup, CF, while a low heat conductor still conducts heat 4x faster than air. You’d still have to be mag dumping to cause swift damage though.

    • Machinegunnertim

      The companies that are making carbon wrapped barrels have ensured that the resin used is specially designed to dissipate heat instead of insulating it. I’d imagine that this sleeve is the same. And the holes should help even more.


    Being very familiar with CF and epoxies, it always worries me when people buy sleeved barrels for the wrong reason. CF”s thermal conductivity levels are low, and it highly dimensionally stable.

    Other than that and it’s strength to weight ratio, a consumer will find very little info about the layup, composite matrix if they used pre-preg, and whether those drill holes will cause unexpected and unseen stress on the layers of CF, especially with UD with a cosmetic 3k weave exterior.

    That many drill holes are highly unnecessary and are likely there for CYA purposes when some dip fart plows through three Magpul D60s thinking he is cool for wasting fifty bucks of ammo in a minute and a half.

    I guess while it is a proven material, I still believe the application for sleeved barrels is for two people:

    1.) Accuracy/low round shooters.
    2.) Fools with money.

    Give me a pencil barrel and with my shooting habits I know I won’t ‘bake’ it… ever. This to me is too flashy with not enough additional benefits to justify the weight or price.

    Also Stainless… how will that hold up in terms of accuracy?

    • neckbone

      Look Gramps, just because you enjoy single shots, don’t begrudge another enthusiast that enjoys full auto. Who cares if someone else wants to do mag dumps with their firearms and ammo? As long as they are responsible.

  • Some Rabbit

    Ahhh, the sweet smell of gimmick.

  • neckbone

    I wonder if I’d rather have 2 Larue barrels in 5.56, or 1 of these? Hmmmm

  • Vhyrus

    The barrel costs as much as a base model AR! Come on people, unless it aims for you this is simply not worth it. You can get a cold hammer forged brand name barrel for half this price.

    • marathag

      Or that worried about heat, use that money to buy another complete upper and swap back and forth as needed.

  • USMC03Vet

    But, Bro. That’s an easy 50 WHP increase on your AR!

    • Beju

      How much if I engrave the BSF logo in my lower receiver?

  • bobinmi

    a fool and his money…

  • JumpIf NotZero

    Protip: All carbon fiber gets its strength from being continuous fibers. All “holes” or cuts into carbon weaken it and are a bad idea. If you see carbon with lots of cuts, it’s only for aesthetic purposes.