Carbine or mid-length

Discussion in 'AR-15 Discussion' started by WhaleNoises, Oct 17, 2011.

  1. WhaleNoises

    WhaleNoises New Member

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    I'm looking at doing a BCM rifle and I'm trying to decide on length. I really like the way the carbine looks but I've been told I should get mid-length for the gas system to work better. I wanted ur opinion. The other info on the gun so far is, I will be using it for plinking target practice. It will be used for SHTF but until then, just targets. I will have it chambered in 5.56 and will probably be the cheap stuff. The barrel is 1 in 7 twist.
     
  2. JonM

    JonM Moderator

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    The purpose of carbine length gas system is to work with the military m16 m4 carbine's 14.5 inch barrel. This barrel length is also the root cause of people carping about the lack of power in the 5.56 round. Chopping the barrel off by almost 6 inches does make it easier to use at very very short range but it also turns the 5.56 into a round very close to a 22magnum...

    The 1:7 twist is used by the military to stabilize the longer tracer rounds.

    My opinion:

    Unless your running a sbr your better off going midlength. Unless you plan on using tracer or need to stabilize very very heavy bullets a 1:8 or 1:9 is better. As the slower twist will get decent accuracy out of cheap 55grn bullets.
     

  3. WhaleNoises

    WhaleNoises New Member

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    What's a sbr? Or what I mean is is a 16" and shorter considered a sbr or is it like the 14.5" and shorter?
     
    Last edited: Oct 17, 2011
  4. Sniper03

    Sniper03 Supporting Member Supporter

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    Whale,

    If the rifle is of good quality and has the proper gas port size, I have never found any difference in reliability between the CAR and the Mid-length ARs.
    There are reasons why this opinion has came about. That being companies putting in the wrong sized gas port in the barrel. For example the Mid-length requires a larger gas port hole in the barrel than the Car Length barrel referring to the 16" barrel for example. If they were to put too large a gas port in a Car application it would in all probability have too much gas and cause the rifle to run Hot! or out of time. This equals to feed and extraction issues. But should that occur most would say that the CAR was not reliable! This situation has occurred more times in the past in the industry than we would like to speak about! So the mystique of the Car not being as reliable has come about. Either, if built correctly and with the proper specifications is no less reliable than the other. You will hear the same argument when it comes to the gas impingement and gas piston systems for the same reasons.
    I will admit the Gas Piston System keeps the inside of the receiver a little cleaner. So we are back to personal preference. I prefer the Mid-Length for two reasons. #1 Longer Sight Radius on the irons and #2 much more mounting surface if using a quad rail to mount accessories ie Lights, Optics, Vertical Grips and etc. I have both but like the Mid-Length the best. Take a look at the Rock River Arms Website and look at the CAR Model Govt.1000. You will see what I mean about the congestion of mounting a good light on the CAR length rifle compared to the Mid-Lengths pictured there. Good luck with your selection. :D

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  5. Sniper03

    Sniper03 Supporting Member Supporter

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    Whale

    SBR Stands for Short Barreled Rifle and is any rifle barrel under 16" without a Flash Hider or Muzzle Break. Some guys go with a 14" Barrel but the Flash Hider or Muzzle Break must be braised and pinned to the barrel to make it non removable and total of 16" Like a Vortex Flash Hider which when braised and pined makes it a true 16" barrel. Anything less is a NFA Rifle regulated by the National Firearms Act/ATF the same as a class III weapon and paperwork and payment of $200+ dollars for the Federal Stamp. In addition when it becomes an NFA weapon it is for ever!. I would not recommend even going there. In most cases the advantage of reducing the AR barrel by a few inches doesn't of set the cost and the future hassle should you ever want to trade it in. And certainly effects the ballistics also. May be great for SWAT Entry Teams and etc. operating in close quarters, but for most of us is not worth the consideration or hassle. Unless it is just for the COOL and CHICKS DIG IT FACTOR! :D

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  6. WhaleNoises

    WhaleNoises New Member

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    Well the plan was a 16" barrel so I can change the flash suppresser, but I'm wondering if the added inch and a half or so of the suppresser gets it out of the sbr range. So it would almost be a total barrel length of 18". I want a BCM and I've herd from some guys on this forum that its a good quality rifle, so I will assume they know what they are doing with the gas tube.
     
  7. mjkeat

    mjkeat New Member

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    A midlength BCM will make you happy.
     
  8. Quentin

    Quentin New Member

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    It's up to you. With a true 16" threaded barrel you can swap out muzzle devices easily. With a shorter barrel you must permanently attach a MD that brings the overall barrel/MD length to at least 16" - or register it as a SBR.

    A BCM 16" or 14.5" midlength is a great choice.
     
  9. Gloves

    Gloves New Member

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    i have a mid-length. it made me happy! =D