Mid-length or Carbine

Discussion in 'AR-15 Discussion' started by connectegr, Jun 21, 2012.

  1. connectegr

    connectegr New Member

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    I am happy with my carbine length rifle and have plenty of room for the stuff I want to mount. But, I see a lot of mid-length rifles at the range.

    What at the reasons to choose the different lengths?
     
  2. mountainman13

    mountainman13 New Member

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    Increased range/accuracy as opposed to ease of use in a cqb situation.
     

  3. Quentin

    Quentin New Member

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    The midlength gas system has a longer sight radius, a couple more inches of rail real estate for better support hand position and is softer shooting. It's ideal for a 14.5-16" barrel. Carbine length gas is ideal for 14.5 and under.
     
  4. connectegr

    connectegr New Member

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    I just saw another post that Colt does not offer a mid-length. That would explain why my LE friends have carbine Colts issued to them (but most are 16"). I was looking for a rifle like the Colt and never considered the mid-length. But, about half the rifles at a recent match were mid-length.

    On another note, this forum seems to provide most support to DI rifles. Some of the best shooters at this match were using high dollar, piston rifles. HK, Ruger, etc. A friend who just recently left the Marines and was assigned to SOCOM said SOCOM shooters are also using primarily piston AR's. His first civilian purchase was a HK MR 556A1. He said that Delta and Seal Teams were using a select fire version of the HK. I don't have any personal experience. But, it does appear that some serious shooters are trending toward the piston systems.
     
  5. AgentTikki

    AgentTikki New Member

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    and it looks cooler.....

    just saying ;)
     
  6. AgentTikki

    AgentTikki New Member

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    got this from this article :
    http://www.firearmstalk.com/forums/f20/ar15-primer-beginners-guide-59600/

    Gas Systems.

    There are 2 major types of gas systems that the AR runs on. The first being DI (direct impingement) and the second being piston. DI is the original design. Piston is a relatively new development. There have been forays into piston designs in the past, but it’s only been recently that piston driven ARs have been become popular. The best thing I can do you is show you the pros and cons a piston system offers, it’s your personal choice to decide if it fits your needs. Please understand that since there is no set standard for a piston system, every piston system is a proprietary design that will require different and non interchangeable parts.

    Pros:
    *A cleaner running system. (less fouling of the BCG and chamber, more fouling by the gas block or exhaust)
    *Should be more reliable in adverse shooting environments.
    *Should be easier to clean, (provided you don’t need to remove the hand guards)

    Cons:
    *Costs more than a comparable DI setup
    *Weighs more than a comparable DI setup
    *Harsher recoil impulse (I concede that this is subjective and debatable)
    *Inherently less accurate,(minor)
    *Slower follow up shots (minor)
    *Proprietary parts make it harder, costlier, and longer to replace broken parts.

    Personally, I would only recommend a piston setup if you where looking for a non precision type carbine and need the extra reliability due to your expected shooting environment.

    DI gas systems come in 4 flavors: Rifle, mid-length (middy), carbine, and pistol. The most common types are carbines, with 7” handguards. The next most common types are rifles with 12” of rail. Relatively new developments are midlengths with 9” handguards. Pistols are uncommon and I won’t be going too much into them. Only consider rifle length gas systems for 18+ inch barrels. Both carbine and midlength gas systems can be used for 14” to 16” length barrels. For these lengths, I usually recommend midlengths as their advantages outweigh their disadvantages:

    *Weight: Advantage Carbines. Since the midlength rail/hand guard and gas tube is 2´ longer, it weighs more, not much more, but carbine gassers are clearly lighter.

    *Sight Radius: Advantage Middy. Being able to put the front sight 2” farther from the rear sight is a clear advantage. The longer the better.

    *Longer hand guard rail: Advantage Middy. I admit this is a subjective point, but unless you have freakishly short arms, the carbine length guards are going to be really short for you. Even my 5”1” wife likes the length of the mid length over the carbine.

    *Aesthetics: Advantage Middy. Again purely subjective, and you may disagree with me on this point, but to me a carbine looks unbalanced with the exposed barrel being too long.

    People point out that since the gas port is so much farther away from the chamber and gas pressure should be lower, middies should be inherently smoother and easier on all the reciprocating parts of your carbine. While I agree with this in theory, I’ve personally found that most middies are overgassed. So this makes the whole “less recoil, smoother impulse” debate a moot point. Most builders overgass systems in order to cycle the cheap under powered target and plinking ammo. I’ve personally shot a few middies that were over gassed and recoiled harder than carbines, and vice versa. This is dependant on how the gas port is sized. As a consumer, you really don’t have any control over the gas port sizing of your barrel or have any way to check or measure it, unless you order a custom barrel for your build. Also since it’s better to have a slightly overgassed system (feed all power levels of ammo) as opposed to an undergassed system (only feeds higher powered ammo), I will call it a draw.

    So in my humble opinion, for the minor inconvenience of a few extra ounces of weight, you get a lot more in return with midlengths. Costs are about the same for either option some builders charging a little more for middies.

    Please understand that once a gas port is drilled into the barrel, it is very difficult and expensive to change from a carbine to a middy or vice versa. If you have a carbine gas system, don’t worry too much. If you want a longer rail or hand guard, it is relatively easy to swap out the gas block to a low profile model or modify a front sight base.This allows you to free float a longer rail or hand guard over it. The same can also be done on midlengths and rifle gas systems if you want an even longer rail.
     
  7. Quentin

    Quentin New Member

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    I think you're talking about SBR and comped rifles. Anyway the ones mentioned are fine weapons but most piston ARs in the civilian market are out of that league.

    If you look around plenty of serious operators are using DI and have no reason to change. Go to any magazine stand and you'll read about plenty of reasons to go piston. Most of it is hype. And the real reason they don't tell you - to separate you from your money.
     
  8. AgentTikki

    AgentTikki New Member

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    Amen to that. I had a piston, one of the first ones that bought. Didn't like it, when back to DI and have been happy ever since.
     
  9. MikeJK

    MikeJK New Member

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    ?...................
     
  10. MikeJK

    MikeJK New Member

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    You'll never see any of the pros of a piston system as a civilian and get stuck w/ the cons unless you get ahold of a select fire version.
     
  11. AgentTikki

    AgentTikki New Member

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    I DID.

    I took my piston for a swim..... (in a creek)
    I took my piston for a bath......(mud in a creek bed)
    I took my piston to the sand box....(hey Cali)

    Oh i dropped it and covered it with sand. Well Cali's a desert so sand is EVERYWHERE. And GUESS WHAT?! It ran through a couple mags like a champ.

    But then I though to myself....wait a sec. This AR is not the unreliable pos all the ak guys are saying it is! It runs like a champ! BUT WAIT THERE'S MORE! I took my Spikes 16" DI and took if for a swim, a mud bath, and to the sand box. and GUESS WHAT. It ran like a champ. SO I sold my piston and built another DI LW. To be honest, I didn't run more than a couple mags, with water and mud and sand flying everywhere, it wasn't enjoyable to shoot a filty gun (ya I'm a priss).

    Honestly the only time I miss my piston is when I'm cleaning my guns. I loved my piston at the end of the day. (ya I tend to get lazy when its Miller time)