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  • 300 blk vs 5.56 build

     Maverick updated 10 months, 2 weeks ago 2 Members · 2 Posts
  • Maverick

    Member
    December 16, 2019 at 7:54 pm

    Wanting to build my first AR. Not really a gun guy, but am heavily pro 2A and with the state of politics in this country I figure I better do the getting while the getting is still good. I was an infantryman in the Army so I do have experience with this platform and firearms in general.

    Debating between a 300 and a regular 5.56 build. The only upside to 5.56 it seems is the price of ammo. Ballistics and versatility are heavily in favor of the 300, especially out of shorter barrels (going for 10.5-12 inch). 147 grain supersonic 300 can be had for about 400-450ish a case and 855 ball for about 300 a case.

    If I build this gun its going to get run hard and shot as much as I can. I look at these guns as tools for defense of life and liberty that i hope i never have to use in a civilian capacity, not something to be put in a safe collecting dust. They’re meant to be shot and trained with. Talking a couple/few thousand rounds a month hopefully, so price of ammo does play a factor, along with putting some aside for a rainy day.

    So should i build the 300 with its numerous upsides or should i go with the 5.56 in order to save a good chunk of money on Ammo, thus being to train more? Also wanting to get a can eventually, something else that weighs in favor of the 300.

  • VulgarDesigns

    Guest
    December 16, 2019 at 7:54 pm

    As someone that had this same internal debate and decided for 300BO, build a 5.56 first. The cost of ammo being significantly cheaper means more trigger time. If you adore the platform after building a 5.56, then build a 300BO second learning from all the things you chose the first go around. Had I done it all again the first time, I would have went that route.

  • Sasquatch_be_me

    Guest
    December 16, 2019 at 7:54 pm

    300 was designed around an 8″ barrel. I run a 7.5″ and it’s great. Don’t go sub 10″ on 5.56. Other than that, it’s up to you and what you want out of the gun. Downside of 5.56 is many areas prohibit hunting with it.

  • Spike762x39

    Guest
    December 16, 2019 at 7:54 pm

    If you’re going for that short of a barrel and the ammo cost doesn’t bother you choose .300 blk hands down. You can probably score simple 5.56 upper for cheap somewhere just to have. My protip is to mark your mags or use 1 type of mag for 1 ammo. Like all PMags for .300 blk and all STANAGs for 5.56. A .300 bullet *will* chamber into a 5.56 chamber far enough to fire it but it will blow the whole gun up, so just be careful when working with both.

  • CanoTheFox

    Guest
    December 16, 2019 at 7:54 pm

    I also say 5.56. It and 223 are more available and you have a wider selection of rounds. Plus in boogaloo time it’ll be what most people have so ammo scavenging will be easier

  • englisi_baladid

    Guest
    December 16, 2019 at 7:54 pm

    I really think you are overstating the upsides of .300BLK. 300BLK is a extremely specialist round. Unless you plan to suppress it. And have a need to constantly switch between supers and subs. There are far better calibers. 5.56 being one.

  • AdVerbera

    Guest
    December 16, 2019 at 7:54 pm

    556 first, then 300.

    You can piece together an upper pretty cheap. Then work on a 2nd lower.

  • PrinceAlbertDaddy

    Guest
    December 16, 2019 at 7:54 pm

    I’d go .223/5.56 for a first build and 300 blackout for a second or third. The short range ballistics are better for 300 black but the .223 is better at further distances. Look up “nutnfancy 300 blackout” on YouTube, he does a great job of talking about them.

  • stanleythemanly85588

    Guest
    December 16, 2019 at 7:54 pm

    if you arent going to suppress it dont get 300, go 556 first and get a 300 later

  • reshp2

    Guest
    December 16, 2019 at 7:54 pm

    5.56 and it’s not even close. 300 blk is for suppressor use, there’s virtually no reason for it otherwise.

  • russ257

    Guest
    December 16, 2019 at 7:54 pm

    Go 5.56 for your first. Unless you want to hunt deer with it.

  • stanleythemanly85588

    Guest
    December 16, 2019 at 7:54 pm

    if you arent going to suppress it dont get 300, go 556 first and get a 300 later

  • Rongxanh88

    Guest
    December 16, 2019 at 7:54 pm

    It sounds like that you are wanting to build a pistol and go with a shorter barrel. I would go for 5.56 build for the following reasons

    1. A 10.5″ 556 barrel is still effective with the right ammo. Typically 75-77gr 5.56 pressure loads will still fragment out to 100 meters.
    2. Cheaper ammo. I have 75gr 5.56 “combat” ammo purchased for around 41 cents a round. I also have green tip ranging from 27-30 cents per round for training, and I get steel case for 20 cents per round. I shoot around 700-1000 rds a month and I get lots of training in shooting steel case. Training is way more effective of a training tool than any increases in performance from going with supersonic 300BLK rounds.
    3. 300Blk is great and fun suppressed, but the subsonic rounds aren’t that much more effective than pistol rounds. Supersonic rounds due give you better penetrating capability at the expense of range. And really its increase in effectiveness is debatable. I mean 5.56 does fine as a hog hunting round.
    4. And if you still want 300blk. You can build a second upper as 300blk, train with your 556 gun and use the 300blk for specific purposes.

  • macsspeed

    Guest
    December 16, 2019 at 7:54 pm

    In AR15.com fashion, do both.

    Cheapest route: have a 300 barrel to swap out, everything else is interchangeable.

    More expensive: get/build a 300 upper. Swap uppers, use the same lower.

    Least cheap: build a 300 gun in addition to the 5.56 gun.

    I personally have a 10.5” 5.56 rifle that I’m pretty confident in out to 100 yards. I’m building an AR-10 as a “longer distance” gun, but even then, that’s more of a selfish justification for me to move to the bigger platform (and I’d like to hog hunt with it at some point). Idk what terrain around you is like, but I’m in the city. 5.56 will probably do everything I’d ever need it to in a worst case scenario.

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