223 Ackley Improved

Discussion in 'Varmint Hunting' started by Jayhawk, Feb 6, 2011.

  1. Jayhawk

    Jayhawk Well-Known Member

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    Anyone have any experience with this round. I am looking at rebarreling to this caliber and am not sure if a guy really needs a 26" barrel to get 3000-3100 fps with the Hornady 75 amax. Am looking at a 8-twist possibley 22" long to mid - long range practicing and varminting. Thanks a bunch.
     
  2. Kevin Thomas

    Kevin Thomas Well-Known Member

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    Sounds a bit optimistic to me, since the "improvement" in the 223 isn't all that great. You're already dealing with a case with fairly minimal body taper and a reasonably sharp shoulder. In 223 match rifles, 2,750 with the 77s is already moving pretty good and flirting with pressures. I ran this one (223 AI) out on Quickload with both a 22" and 26" barrel, and went from 2,800, on up to about 2,900 fps. That was with the cyber-pressures running at absolute max, and I doubt I'd be pushing a real rifle quite that hard. Especially when it was my face behind the bolt, if you get my drift.

    If you want 3,000-3,100 fps out of the 75s, I'd say a bigger case is in order, not just a longer barrel.
     

  3. strombeckj

    strombeckj Well-Known Member

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    I couldn’t tell you if the FPS is possible with that bullet/twist combo etc.. But what I do Know is that Quickload is NOT the end all be all when it comes to load development just a GOOD starting point. I shoot a .223 AI with a tight chamber and a 24” krieger 1:14. I can push a 50gr Blitz King with 28.3gr (pet load) of XBR or 28.5gr of X-Terminator, LC & rem 7 1/2 over 3700 FPS which Quickloads will dismiss along with some other people. I do this all day long with no pressure signs and get about 4-6reloads out of the brass. Every rifle is different, start low and work your way up. I am very impressed with this round in my rifle and happy I did it.


    01/15/2011, 50 degree's. 28.3gr XBR



    [​IMG][​IMG]
     
  4. Kevin Thomas

    Kevin Thomas Well-Known Member

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    Never said QL was anything other than a useful tool, and this is one of those examples. However, the question pertained to 75 grain bullets. Having fired a few 77s and 80s over the years, I can assure you, it's going to be hard to hit that 3,100 fps figure without fire-walling the load, and then some.

    In the meantime, if you don't think 3,700 fps is a pressure sign, more power to you.
     
  5. Jayhawk

    Jayhawk Well-Known Member

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    Thanks guys, I might be asking to much from such a little case. I just figured it would be a good economical round using only 25-27grains of powder with hardly any recoil while still having a bullet capable of being supersonic to 1000yds. Barrel life hopefully 5000 rounds?
     
  6. strombeckj

    strombeckj Well-Known Member

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    I would agree that a 1000 yards is pushing it, may want to think about a PPC or BR. My smith has a reamer for a 22x47 that he is working up loads for now. He plans on the 80’s -90gr’ers. Good luck!
    FYI… reloadersnest.com has a couple of 75gr’s getting 2998 FPS w/ a .223 AI.
     
  7. Kevin Thomas

    Kevin Thomas Well-Known Member

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    Jayhawk,
    You've got the twist to handle it, so why not take a look at the 80 grain offerings like the Bergers? They'll stay supersonic at 1,000 with the speeds that are realisitcally possible (say, 2,800- 2,850 fps) with a 223 AI. I have some doubts about the 75, since it's considerably less streamlined than the VLDs. Remember, as German Salazaar always says, velocity's temporary, but BC lasts forever.

    A barrel life of 5,000 rounds is possible, but probably a bit optimistic. Hard to say here, since it means different things to different people. For a hunting gun, I'd say it'll likely make it, especially if the heavy weight bullets aren't the only thing that goes downrange. For a competitive shooter, not so likely. really depends on what you consider to be "shot out".
     
  8. Jayhawk

    Jayhawk Well-Known Member

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    Thanks Kevin, I haven't built the gun yet, still trying to decide on specs. What caliber were you shooting the 77s and 80s in and how far were you shooting them? Strombeckj, don't know much about the 22 BR other than it is has a .308 case head...how much of a bigger case capacity is it than the 223ai? Thanks again guys.
     
  9. Kevin Thomas

    Kevin Thomas Well-Known Member

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    Jayhawk,

    That's either in a 20" Service Rifle, or a 26" Match Rifle being used for XC-HP shooting, chambered in the standard 5.56mm/223 Rem cartridge. The normal course of fire goes from 200 to 600 yards, but the 80s have seen extensive use out to 1000 yards as well. Pretty marginal out of a Service Rifle, but they do perform well out of a Match rifle. That extra 6" makes the difference. Running the 80s at 2850 out of a Match Rifle is doable at sane pressures, and the bullet will stay supersonic all the way out. The 77s won't, and while I've never seen the Hornady 75s used for this, I have no doubt that they'd go transonic before reaching the target. Not a good thing.

    There's also been a push towards the 90 grain bullets, but these are a bit more problematic in a Service Rifle. Those who've had the best results with them are usually using them in a Match Rifle, and still pushing them pretty hard.

    The BR has about a 5 grain water capacity advantage over the 223 AI, which in turn has about a 2 grain advantage over the standard 223 Rem; 36 grains for the BR, 31 grains for the 223 AI, and just a tad under 29 grains for the 223 Rem.

    Hope that helps.
     
  10. J E Custom

    J E Custom Well-Known Member

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    There are lots of info on the 223 ai on the other thread starters like Rifles Bullets barrels and ballistics
    if you do a search.

    It is a great little round and the AI version ups the velocity by 100 to 150 ft/sec. Also you can shoot
    factory loads in it with good accuracy and fire form at the same time.

    I built an 223 AI on a Sako S 491 bolt action and it put the fun back in shooting the .223 rem.

    J E CUSTOM
     
  11. woodnut

    woodnut Well-Known Member

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    I have an AR15 with an ISSI upper in 223 A.I. and a 14 twist ,26" barrel. Mine LOVES the 55gr. Sierra Blitz Kings.
    This part is going to be very hard to believe; but I swear it's the truth. I am getting a tad over 3600fps and shooting bug holes ! I have a Nightforce 8x32x56 on it; but I am sure another good scope would do it. Impossible ,you say? I thought so before I chronoed the loads. Not great case life ! Primer pockets swell up after three ,maybe four loading. Yes, that's a heck of an increase in speed from 223 to A.I. and yes, A.I.s usually only give an extra 100 to 150 fps. P.O. Ackley may not have ever done the 223A.I. as he wasn't fond of the cartridge. But he should have! This is 22/250 velocities in a iddy bitty 223 case ! Go figure. I can't explain it; but Lee at ISSI says the same thing about it.
    As for shooting 100 yards; I think you need something else. Yes, they do shoot it. But, there's other rounds more able.
    If varmint hunting and max. 5-600yard shooting is what you'll do mostly; it's hard to beat the 223 A.I.