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  1. #1
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    BCM 14.5" Midlength Upper Receiver Group




    Bravo Company MFG (BCM) is well known in the weapon community for their solid weapon components, and we recently had a chance to grab one of their newest 14.5" barreled upper receiver groups for review.

    The 14.5" barrel is what is used on the issue Colt M4, and the M4 gas system is of the standard carbine length. Used for years, the carbine length gas system has a few areas that it looses in when compared to a midlength gas system, which pushes the gas block (or Front Sight Base) out an additional two inches. I've been accused of being a little too fascinated with technical details, so I'll touch on a few of the high points of the midlength gas system. The extra 2 inches of gas tube provide for an altered dwell time as the weapon is unlocking, which results in less wear and tear on the weapon, as well as increased relaibility. In addition, it alters the felt recoil to a bit more of a push. I'm not claiming the recoil of the 5.56 is severe by any stretch, but less is always more when you are trying to get rounds on target quick. Especially if that target is shooting at you. The midlength also pushes out the Front Sight Base out farther, and that increased sight radius allows for more accurate shooting for those times when you are using your iron sights.

    Below, we will take a walk through of the BCM 14.5" Midlength Upper Receiver with permanently attached flash suppressor (FS). In this case, I'm using some of the given specs off the BCM website, and illustrating those points, as well as commenting on what strikes me as important or interesting.



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  2. #2
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    The 14.5" barrel comes with a permanently attached muzzle device. BCM gives you a choice of different muzzle devices, and in this case we are seeing the PWS comp. This comp does a good job of controlling muzzle rise, and even tames a bit of flash. In addition, it brings the over all length (OAL) to a legal 16" when pinned and welded. The PWS comp is timed perfectly, which is the first of many clues we have into the quality of this upper

    You can also see in this image that the FSB uses the standard military front sight post (FSP).

    Barrels specs are listed below.

    Mil-Spec 11595E - Barrel Steel

    BCM barrel steel is Mil-Spec per MIL-B-11595E. This grade (CMV) of steel is a Mil-Spec steel used in the USGI M16 family of rifles; it is stronger and will last longer than the typical barrels offered in the commercial market. The Mil-Spec grade steel gets its’ additional strength and rigidity from an increase in carbon and/or vanadium in the alloy. This will offer increased barrel life and performance through use in all types of extreme environments and temperatures.


    Chrome Bore and Chamber


    One of the first modifications that were made to the original M16 in the mid 1960’s 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.

  3. #3
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    BCM shows an obvious weld on the underside of the PWS comp. This is done to make it painfully clear to any prying eyes that this is a legal barrel. The barrels are perkerized, with the BCM specs being listed below.


    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.


  4. #4
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    Inspection of the FSB shows solid taper pins, a coated sling swivel, and a properly marked "F" Front Sight Base. A check of the gas tube roll pin shows it is centered and free of mushrooming on either end.

    Mil-Spec F-Marked Forged Front Sight Bases

    Mil-Spec for rifles issued to the troops require taller front sight bases on all flat top AR rifles. Many commercial offerings use M16A2 height front sight bases on all of their barrels regardless of what type of upper it is installed on. As a result, owners of rifles and carbines with the flat top receiver configuration can have problems getting a proper 'zero' for elevation with Mil-Spec back up iron sights. As all of the BCM uppers are built for flat top uppers, all have the proper Mil-Spec F marked front sight base to insure the correct height for iron sight zeroing when using military iron sights. Mil-Spec taper pins secure the forged front sight base with the sling swivel secured by tubular rivets.



  5. #5
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    The below shown M4 feedramps are well matched to the barrel extension. You can also see in the below picture that the weapon is test fired at the factory, a reassurance for those who obsess about QC (like me).

    BCM shows a chrome lined bore as well as a NATO 5.56 chrome lined chamber.

    Chrome Bore and Chamber
    One of the first modifications that were made to the original M16 in the mid 1960’s 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.

    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.



  6. #6
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    Overall weight of the upper receiver is reduced by use of a government profile barrel. In this case, the Daniel Defense LITE rail is installed which prevents me from showing the full barrel profile.



    Government Barrel Profiles
    Duty rifles are built to be carried - day in and day out. The USGI barrel profiles (often referred to as the Government Profile) enable the operator to carry their weapon for longer periods of time and deploy them faster than the heavier commercial H-Barrel counterparts. The government profile barrel is also compatible with the current M203 mounting systems.


  7. #7
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    The 1:7 twist barrel is proof fired, and magnetic particle inspected. While this might seem like a a small technicality, these steps allow only the highest quality barrels to make it through the screening.



    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.



  8. #8
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    Installation of the Daniel Defense 9.0 Lite rail is absolute perfection. The alignment of the upper to rail is exact, and checking the interior of the upper receiver shows a perfectly centered gas tube.

    The Daniel Defense 9.0 Lite rail is made of aircraft grade 6061-T6 Aluminum, and is military specType III Hard Coat Anodized. Total weight of the rail is 11oz, making it one of the lightest rails on the market. Light doesn't mean weak, and Daniel Defense has taken the route of welding the rail to the interior collar, creating high strength that is unaffected by heat or solvents.







  9. #9
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    The BCM upper receiver is machined with M4 feedramps, engraved with T-marks, and is hard coat anodized.

    Optional on this upper receiver group are the BCM/ Troy rear sights. These are well known, and are probably the most popular BUIS (Back Up Iron Sight) on the market. Below are the specs as taken from the BCM website.


    * Dual peep, same plane aperture allows for perfect co-witness of red dot and holographic optics

    * Offset plane 300m models are also available (FBS-RA2)

    * Full Windage adjustment knob located in same position as standard M16A2, A3, A4 weapons

    * Each click equals .25 MOA (M16A4 rifle) and .33 MOA (M4 carbine) shift in impact

    * Sight is easily installed and deployed by simply pulling up without any levers buttons or springs

    * In the up position, a stainless steel cross-lock provides 1000 pounds of shear strength

    * Sight works in conjunction with all standard height front sights

    * The cross-lock guarantees return to zero, eliminates all wobble and the possibility of accidental folding

    * A release button is depressed to fold. The internal ratcheting wedge retains sight in folded position

    * Low profile snag resistant design. Protects Level A&B Gear from damage and can be decontaminated.

    * Precision machined Aircraft T6 Aluminum Billet and Stainless Steel Construction

    * Military Specification Black Hard Coat Anodizing (Teflon impregnated) and Black Oxide stainless



  10. #10
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    Another option worth strong consideration is the BCM Gunfighter Charging Handle. Benefits of this Charging Handle are documented below.

    You can also see a lengthy review at the below link.

    http://militarytimes.com/blogs/gears...arging-handle/

    The BCMGUNFIGHTER™ Charging Handle offers two significant advantages.

    1. Since the tiny roll pin is no longer the weak point - it is a much stronger system and tactical latch will stay intact even under repeated support side only manipulation.

    2. With the force kept inside the body of the handle, when the handle is pulled directly to the rear, it moves directly to the rear and does not angle off to the outboard side. A much smoother operation.





  11. #11
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    While you can purchase the BCM upper without the Bolt Carrier Group (BCG), it makes little sense when BCM makes one of the highest quality Bolt Carriers available. Check out the below specs and you will find that they mirror what the military requires.


    - Milspec Carpenter No. 158® steel
    - Chrome Lined Carrier (AUTO)
    - Chrome Lined Gas Key
    - Gas Key Hardened to USGI Specifications
    - Grade 8 Hardened Fasteners
    - Key Staked Per Mil-Spec





  12. #12
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    The bolt is obviously part of the BCG,and the specs are shown below. The picture shows the disassembled bolt, along with the M16 firing pin and bolt cam pin.


    -HPT Bolt (High Pressure Tested)
    -MPI Bolt (Magnetic Particle Inspected)
    - Shot Peened Bolt# Tool Steel Extractor
    - BCM Extractor Spring
    - Black Extractor Insert


  13. #13
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    The Charging Handle and Bolt Carrier Group slide in the upper receiver they way they should. If you have ever used some of the off name brands, and compared them to a issued military weapon, there is often a different feel. With the Bravo Company MFG upper, the feel when charging the weapon is the same. Its not something that can be put easily into words, but its tangible.





  14. #14
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    Here are a few pictures that show the upper on a BCM complete lower receiver.


    The sum of the parts is very high, and its clear that Bravo Company MFG takes their product line very serious. With the specs and lineup that BCM takes to the table, its also clear that there is a good reason they are looked at as one of the highest quality options available.







  15. #15
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    For more information, take a look at the Bravo Company MFG webpage or for custom build info and more options, check out the Bravo Company USA website.


    http://www.bravocompanymfg.com/



    http://www.bravocompanyusa.com/



    BCM Midlength Upper Direct Link





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