BCM® Exclusive Design

• Continuous medium taper designed for optimal weight, balance, and performance on a semi-automatic carbine.
• Medium tapered preferred for select fire carbines.
• Heavier profile toward the rear near chamber area.
• Thinner tapered profile out front.
• No sharp handguard cap shoulder for improved barrel harmonics.
• Please note for gas block selection, barrel journal measures .750"
• Approximate Weight: 1lb 10oz

These are stripped 14.5" Mid Length Standard 11595E barrels with gas ports installed and dimpled for a strong gas block installation.

M4 Feed Ramp Barrel Extension

In developing the USGI M4 carbine as one of the primary weapons for todays infantry, some modifications were performed to the original M16 platform to enhance the reliability of the shorter barreled carbines. With the shorter carbine gas system and the increased gas port pressure, the carbine cycled faster, and at times the cycle rate could be faster than the magazine would feed ammunition. One of the modifications done to increase reliable feeding included enhancing the angle and the length of the feed ramps. This USGI modification was done to both the barrel extension and the upper receiver, creating a longer and steeper feed ramp. These Mil-Spec M4 feed ramps are part of the original CNC manufacturing process. As a result, the factory machined M4 feed ramps on the receiver are hard coat anodized which adds significant strength to the aluminum. This feature is offered on all BCM barrels.

USGI 1/7 Twist Rate

The USGI 1/7 twist rate of all of the BCM barrels is the preferred twist rate by most professional infantryman. This twist rate has proven very versatile and can effectively run the new heavier 5.56 ammo that is hugely popular with military and private security personal for its superior ballistics.

Chrome Bore and Chamber

One of the first modifications that were made to the original M16 in the mid 1960s was the addition of the chrome lined bore and chamber. It is now a world wide standard in the industry for a battle rifle. The chrome bore and chamber is harder than the barrel steel and on the USGI M16/M4 rifles will aid in chambering, extraction, and reliability. It increases velocity, and also resist against fouling and corrosion from extended use in the field. This gives the end user a longer barrel life with less required time in maintenance and cleaning.

Manganese Phosphate Barrel Finish

Barrels are parkerized with the manganese phosphate finish (Mil-Spec A-A-59267). Military specifications also state that the entire barrel surface is phosphate finished to create a porous surface to absorb oil as to resist against corrosion from the elements. BCM barrels are phosphated before installation of front sights. This is a much more extensive assembly operation, but insures that the entire barrel is finished and protected . . .even under the front sight base.

5.56 NATO Chambers

The USGI 5.56 NATO chamber is the best choice for effective deployment, reliability, and compatibility, of higher chamber pressures of military ammo.

HPT / MP Inspected Barrels

Military specifications require that barrels undergo a HPT (High-Pressure Test) load as a part of quality assurance procedures. Commonly referred to as a proof load, the M197 HPT is rated for 70,000 psi. BCM barrels are proof loaded and then MPI (Magnetic Particle Inspected) to detect any possible flaws in the barrels surface. The barrels are MP inspected with both circular and longitudinal magnetic fields per ASTME1444-01 (current Mil-Spec) to assure a high quality finished product. All BCM barrels are marked HP MP as our proof load marking.