GUN School me on 18" ARs

Discussion in 'On Topic' started by zumin3k, Dec 6, 2008.

  1. zumin3k

    zumin3k New Member

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  2. LancerV

    LancerV Something Happened OT Supporter

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    For that faster velocity really so a slightly flatter trajectory.
     
  3. yar1182

    yar1182 New Member

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    I'm mostly framilar w/ 18" AR's from 3 gun competition as this is the most popular configuration.

    The 18" barrel is a good compromise for weight, muzzle velocity, manuverablity, and recoil management.

    One of the primary concerns when shooting run and gun competition is having a manuverable gun you can run with and work in and out of ports and in awkward positions. The 18" barrel w/ a 3" compensator ends up to be a 20" overall lenght. For 3 gun this is as long as you want to go. The 20" barrels w/ a 3" comp are just too long.

    The popular taper for a 18" barrel for competition is the light weight or ultra light. The barrel is 3/4" behind and in front of the gas block, or 3/4" behind and 1" in front. These are not pencil barrels but much lighter than a hbar or bull barrel.

    For recoil manangement a 18" barrel should have a rifle lenght gas system. There are 3 lenghts of gas systems carbine which is the shortest and has the most recoil and typically seen in barrels 16" and under, a mid lenght system which is seen in barrels 16" to 18" and rifle which are seen in 18" and longer. Add a good compensator to the barrel and you got a gun with very little recoil. The 223 has light recoil to begin with but when your shooting long range targets 350+ yards you can see your misses and make corrections or wind calls. If your shooting varmits you can "Watch the movie".

    For 3 gun competition your ammo has to make a certain muzzle velocity. We call this power factor. If your ammo does not make power factor you shoot for no score. The bulk factory 223 in 55 grain flirts with missing power factor in a 16" barrel. Those that shoot the 16" barrels have to be very careful with their ammo selection or shoot somthing hoter and heavier than 55 gr. The 18" barrel makes PF with just about all 55gr ammo.
     
  4. zumin3k

    zumin3k New Member

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    I don't plan on doing any 3 gun competitions, and I've already got a 14.5" setup, so I just wanted something a little different and maybe a little more long range potential. Sounds like it will fit my needs.
    So who makes a good 18" rifle length gas setup? My next build will be on the cheap.
     
  5. yar1182

    yar1182 New Member

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    18" barrels are generally more expensive. Not sure why, just because the people who buy them are willing to spend more money or it's trendy I guess.

    I don't buy any cheap stuff, I buy the best stuff if at all possible and gladly pay the mark up. The barrel I like is from JP rifles www.jprifles.com
     
  6. idleprocess

    idleprocess Bring a dollar with you baby in the cold cold grou

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    14.5", 16", and 20" AR barrels seem to be pseudo-"commodities" in the firearms world; other lengths are more niche usage and probably don't see the huge sales numbers to make them readily available everywhere - thus their greater price.
     
  7. zumin3k

    zumin3k New Member

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    Maybe I should check out a 16" or 20" instead then.
     
  8. yar1182

    yar1182 New Member

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    After the mgm ironman I am going to rebarrel w/ a 16" JP ultra light. I was big on the 18" barrels for the long range stuff but have since figured out it is more scope and ammo. I think I can get a bigger advantage by having a lighter more manuverable rifle to take advatage of my foot speed.
     
  9. zumin3k

    zumin3k New Member

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    Thanks for the input:h5:
     
  10. fatmoocow

    fatmoocow bored OT Supporter

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    I don't have the numbers anymore but I wan to say a noveske 18" with the magic rifling get's pretty close to a standard 20" in velocity. You're paying top dollar for that though and it's pretty heavy. It really all comes down to what you're using it for. I personally want a little extra range incase of zombie attack, but if on Z-day you plan on clearing lots of rooms a shorter barrel may be a better fit for you.

    If I had the money I'd get myself the 13.7 or whatever it is with a noveske pig so then I'd have a short range 16" legal light weight blaster. Because I paid out the ass for the Vltor VIS I can swap back and forth easily.

    That said before I bought any new parts I'd buy a life time supply of ammo and mags and then maybe some glass. Who knows what crazy shit the dems will try to pass with microstamping or serialized ammo.
     
  11. zumin3k

    zumin3k New Member

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    I think I'm going to end up building an A4gery to go with my M4gery.
    I might have to sell my CETME to pay for it :(
    Now to find someone that has decent prices on lowers...
     

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