Optimum Length (Not what you think)

Discussion in 'Varmint Hunting' started by tdregs13, Jan 22, 2012.

  1. tdregs13

    tdregs13 Member

    Sep 3, 2011
    I am on the search for an AR-15 varmint/target rifle that I would be shooting out to about ~500yds. I was wondering what the optimum barrel length would be and what contour barrel as well. I know a heavy-contour varmint barrel would be ideal but I'm not going to be sending tons of rounds down range either though.
  2. bruce_ventura

    bruce_ventura Well-Known Member

    May 22, 2011
    18-20" should be fine. If you handload, you probably don't need a bull barrel to get sub-1"" 5-shot groups- look at government contour. White Oak Armament makes some nice uppers for varmint/target use. They are heavy, though. Without handloading, you can probably get by with an HBAR contour.
  3. strombeckj

    strombeckj Well-Known Member

    Nov 24, 2010
    Optimum length in relation to what? Accuracy? or FPS? Barrel length has little to no effect on accuracy. FPS is a different story, you need a barrel long enough to get full powder burn before the bullet leaves the muzzle. I have been told by many smiths that the best length for a .223 case is around 22"-24" for the highest velocity.

    Contour effects the barrels harmonics which effects accuracy, it also helps dissipate heat which leads to erosion of the throat and barrel. I have light barrel rigs that shoot lights out for the first few shots and then have a tendency to open up more quickly then my heavy or sport weight rigs

  4. 77ruger

    77ruger Member

    Jan 15, 2012
    RRA 24" 1-8 twist varmint. Unbelievable accurate. I load 60 gr Vmax & Varget under .25" at 100 yds. This works for me...
  5. dogbuster0006

    dogbuster0006 Well-Known Member

    Dec 6, 2011
    I have a yankee hill machine black diamond specter, barrel is only 16" with 1/9" rifling but, shooting good ammo horandy 55gr v-max i get one ragged hole at 100yd and 3/4-1" groups at 200yd. I haven't shot it past 400 but at that range it's well within minute of coyote, I can hit standard size clay pigeons at that distance with boring regularity.
  6. rdsii64

    rdsii64 Well-Known Member

    Dec 11, 2008
    Optimal barrel length will depend on powder burn rate.
  7. neutral

    neutral Active Member

    May 8, 2010
    depends...... not the diapers

    I have a 26 in 1-9 ss barrel from mcgowen barrels and i love the length. its .8 contour and end with a target crown. I'm not sure if what i'm about to say is right so correct me if i'm wrong but i feel that the longer barrel has allowed me the flexibility of shooting slightly heavier bullets due to the bullet having slightly more time in contact with the rifling. lately i've been playing with 69 and 75 grain sierras as well as 68gr hornady match bullets and when i loaded them nice and tight to the lands i was amazed with the results. single holes at 100 and cloverleafs at 200 easy. thats of course if im able to do it that day. ( heart beat in the scope seams to be my major problem)

    as for the coutour. does it look good? and is it too heavy? i love my heavy barrel and before i had it my sport barrel was a tac driver too. it did open up when it got hot and so far my heavy barrel has been amazing and keeping accuracy in the heat. Fluting should help but lets be honest. it looks badass. i wish i would have got it done when i ordered my barrel.

    i just got some 75 gr amaxs finally so i hope they do as well as the match bullets. One thing that was really weird. since i started seating my bullets long. ( 2.3 for the hpbt match) ive had insane consistancy even between the loads and bullets. the 75s were within an inch of the 68s and same with the 69s.
  8. Greyfox

    Greyfox Well-Known Member

    Jan 21, 2008
    I have tried various lengths and contours in the 300-500 yard range. My all out favorite as far as accuracy and consistency, cold bore/hot bore, is my DPMS 24" varmint barrel upper with a 1:9 twist. This rifle is awfully heavy and bulky but will hold .25 MOA consistantly using 69gr SMKs and I have not had to re zero for the last 2100 rounds. I have a couple of H Bar barreled uppers in 16- 20" lengths also 1:9 twist but they run .75-1 MOA and require zero checks and adjustments for best results at the longer distances. Interestingly, I have a Remington R-15 Varmint with the 26" triangular barrel in 1:9, 24" barrel that performs just about as well as the DPMS, but is a lot lighter and more manageable for carrying when coyote hunting. I was very skeptical about this rifle at first, but once I put a decent trigger in it, I found it to be my preferred long range carry rifle for coyote hunting.