AR 6.5 Grendel vs. 5.56 vs. 300 AAC Blackout

The #1 community for Gun Owners in Indiana

Member Benefits:

  • Fewer Ads!
  • Discuss all aspects of firearm ownership
  • Discuss anti-gun legislation
  • Buy, sell, and trade in the classified section
  • Chat with Local gun shops, ranges, trainers & other businesses
  • Discover free outdoor shooting areas
  • View up to date on firearm-related events
  • Share photos & video with other members
  • ...and so much more!
  • hacksawfg

    Expert
    Rating - 100%
    6   0   0
    Mar 8, 2012
    1,368
    38
    Hopefully not Genera
    So I'm putting together my first AR. Have pretty much all the stuff for the lower, looking at starting to pull the upper parts together, but I notice a shortage of stripped uppers and 16" 5.56 barrels.

    Bearing in mind the purpose of the gun (truck and trail mainly, maybe some hunting), and since it looks like I'm going to have to wait anyway for a barrel around $200 or less (budget), should I go 5.56 or take the added power of the 6.5 Grendel or 300 AAC?

    BTW, this is my FIRST AR, so I don't already have a 5.56.
     

    95wrangler

    Sharpshooter
    Rating - 100%
    4   0   0
    Sep 10, 2011
    609
    18
    New Pal
    I ordered a Green Mountain barrel at the end of last week. It was a production over run. $153 got me a 16" chome lined m4 1:7 twist. Cant wait for it to arrive!
     

    Jarhead1775

    Marksman
    Rating - 100%
    1   0   0
    Nov 21, 2012
    155
    16
    Rushville
    If you want it for hunting also I would go with 6.5 Grendel.

    If you build it in pistol configuration, the 6.5 Grendel cartridge fits right in line with Indiana's pistol configuration requirements. It is larger than .243 in diameter and under the max cartridge length of 1.8. You can additionally either build another lower with your rifle stock or document the build as a pistol and then throw a buttstock on it (now making it a Rifle) to go to the range with or when you are not hunting.... provided the barrel length is appropriate for a rifle or you have your Tax stamp for a SBR.

    You can go from a pistol to a rifle and back to a pistol, but you cannot go from a rifle to a pistol after it is initially built as a rifle.

    There is some foot work involved in this, but then you have something you can hunt and play with legally in Indiana.
     

    CBR1000rr

    Expert
    Rating - 100%
    5   0   0
    Feb 26, 2011
    766
    18
    In an eastern valley
    I don't know much about the differences in the cartridges, but I would vote for 5.56 unless you reload. If you reload I would recommend the 300 blk out.

    Here is my reasoning:

    1. 5.56/223 is ever where
    2. 5,56/223 can be found for next to nothing
    3. None of the listed cartridges will be usable for hunting (except Jarhead's explanation)


    If you want to switch from one to the other, it is simply a barrel change to go from 5.56 to 300 blk out and vise versa.

    :twocents:
     

    95wrangler

    Sharpshooter
    Rating - 100%
    4   0   0
    Sep 10, 2011
    609
    18
    New Pal
    I guess I was saying the barrels are out there for 5.56. I got my stripped Aero Precision upper at Bradis on sunday and DS Arms has a complete upper reciever in stock as of saturday. You can always build 2 uppers of different caliber. Ill probably build a 6.5 or 6.8 next then a .300! All this and the 5.56 is my first build and Im planning build # 3!
     

    melensdad

    Grandmaster
    Rating - 94.7%
    18   1   0
    Apr 2, 2008
    23,984
    77
    Far West Suburban Lowellabama
    I'm a huge fan of the 6.5 Grendel. Currently own 2 of them and am in the process of converting a bolt action rifle to 6.5 Grendel too.

    HOWEVER, the Grendel really loves midlength and long barrels. If you really want a 16" barrel then I would pick the 300 AAC Blackout. If you are willing to go up to a 18" barrel then the Grendel will begin to really shine and will preform better.
     

    kludge

    Grandmaster
    Rating - 100%
    5   0   0
    Mar 13, 2008
    5,360
    48
    the 6.5 Grendel cartridge fits right in line with Indiana's pistol configuration requirements. It is larger than .243 in diameter and under the max cartridge length of 1.8.

    Max length only applies to hunting deer with rifles.
    There is no max length for hunting deer with pistols.
     

    Jarhead1775

    Marksman
    Rating - 100%
    1   0   0
    Nov 21, 2012
    155
    16
    Rushville
    Max length only applies to hunting deer with rifles.
    There is no max length for hunting deer with pistols.

    I apologize, you are correct. I tied the 2 together.;)

    Handguns, other than muzzleloading, must have a barrel at least 4 inches long and must fire a bullet of .243-inch diameter or larger. The handgun cartridge case, without the bullet, must be at least 1.16 inches long. Full metal-jacketed bullets are not permitted.
     

    hacksawfg

    Expert
    Rating - 100%
    6   0   0
    Mar 8, 2012
    1,368
    38
    Hopefully not Genera
    chin.gif


    Lots to think about. Let me pose this question (let's take hunting out of it for now). Is the better performance of the 6.5 or 300 worth the additional cost of ammo? I probably won't be running hundreds of rounds through it each month. Availability of ammo could be a concern, but I'm guessing when I buy a worst case SHTF gun I'm probably better off with an AK anyway (and I say that because it's been shown you can build one from a shovel).
     

    Jarhead1775

    Marksman
    Rating - 100%
    1   0   0
    Nov 21, 2012
    155
    16
    Rushville
    A portion of that question depends on if you reload or not.....

    Another portion depends on how far you want to be able to shoot accurately.....

    Another portion depends on the performance that you want throughout the entire range (muzzle to target) an example would be shooting in the wind.

    I'm not trying to be difficult, but now that you opened up the discussion further... it requires more information.
     

    downzero

    Master
    Rating - 0%
    0   0   0
    Jun 16, 2010
    2,965
    36
    I apologize, you are correct. I tied the 2 together.;)

    Handguns, other than muzzleloading, must have a barrel at least 4 inches long and must fire a bullet of .243-inch diameter or larger. The handgun cartridge case, without the bullet, must be at least 1.16 inches long. Full metal-jacketed bullets are not permitted.

    It's pretty amusing to me that I could hunt a deer in Indiana with a 9mm Luger shot from a Glock 19. I wouldn't recommend it, but I could certainly meet those restrictions.

    I'm a huge fan of the 6.5 Grendel. Currently own 2 of them and am in the process of converting a bolt action rifle to 6.5 Grendel too.

    HOWEVER, the Grendel really loves midlength and long barrels. If you really want a 16" barrel then I would pick the 300 AAC Blackout. If you are willing to go up to a 18" barrel then the Grendel will begin to really shine and will preform better.

    This makes no sense. If a barrel length and case doesn't have sufficient powder capacity for a 6.5mm bullet, it certainly isn't going to make things any better by using a smaller case with less powder capacity and a larger, 7.62mm, heavier bullet.

    300 Blackout is a specialized cartridge that is designed (most importantly) for subsonic use out of (usually) an SBR with a suppressor. It can be used supersonic out of a 16"+ barrel and without a suppressor, but the result would essentially be an underpowered AK round with the ergonomics of an AR--not exactly the intended audience for the cartridge.

    My answer to the original poster is that if you don't already own a 5.56 AR, that's what you should stick with. If you want more range and power out of (any) length barrel, the 6.5 Grendel will give it to you, at the expense of far more expensive factory ammunition and, as melensdad suggested, 16" isn't enough barrel to get the full potential of the 6.5 Grendel (but it isn't sufficient to max out the velocity of a 5.56 cartridge, either).
     

    hacksawfg

    Expert
    Rating - 100%
    6   0   0
    Mar 8, 2012
    1,368
    38
    Hopefully not Genera
    A portion of that question depends on if you reload or not.....

    Another portion depends on how far you want to be able to shoot accurately.....

    Another portion depends on the performance that you want throughout the entire range (muzzle to target) an example would be shooting in the wind.

    I'm not trying to be difficult, but now that you opened up the discussion further... it requires more information.

    Not a reloader (yet, just found out today I'm going to need to replace my furnace in the near future, so reloading equipment/classes aren't in my immediate plans).

    As far as for my first build, I would like it to be jack of all trades gun. As far as range goes, optics I'm planning on are 1x-4x at most, or a red-dot. Within 200 yards basically.

    Hopefully that helps.

    <EDIT> after downzero's post and some of the other stuff I've seen, I'll pass on the 300. So lets leave it between the 6.5 and 5.56.
     

    downzero

    Master
    Rating - 0%
    0   0   0
    Jun 16, 2010
    2,965
    36
    Not a reloader (yet, just found out today I'm going to need to replace my furnace in the near future, so reloading equipment/classes aren't in my immediate plans).

    As far as for my first build, I would like it to be jack of all trades gun. As far as range goes, optics I'm planning on are 1x-4x at most, or a red-dot. Within 200 yards basically.

    Hopefully that helps.

    And what are you going to shoot with it? Just paper?
     

    42769vette

    Grandmaster
    Industry Partner
    Rating - 100%
    52   0   0
    Oct 6, 2008
    15,222
    113
    south of richmond in
    Not a reloader (yet, just found out today I'm going to need to replace my furnace in the near future, so reloading equipment/classes aren't in my immediate plans).

    As far as for my first build, I would like it to be jack of all trades gun. As far as range goes, optics I'm planning on are 1x-4x at most, or a red-dot. Within 200 yards basically.

    Hopefully that helps.


    The best explination Ive heard of the Vortex PST 1-4 is that its a jack of all trades scope. Its not quite as nice as a aimpoint at 10 yards, its not quite as nice as a acog at 500 yards, but it will do both
     

    hacksawfg

    Expert
    Rating - 100%
    6   0   0
    Mar 8, 2012
    1,368
    38
    Hopefully not Genera
    And what are you going to shoot with it? Just paper?

    That, and possibly hogs. Either way, I'm getting the sense that 5.56 is probably better to start with, 6.5 may have better ballistics but the costs associated with it probably wouldn't justify going that route at this time, since I don't currently reload.
     

    Jarhead1775

    Marksman
    Rating - 100%
    1   0   0
    Nov 21, 2012
    155
    16
    Rushville
    Not a reloader (yet, just found out today I'm going to need to replace my furnace in the near future, so reloading equipment/classes aren't in my immediate plans).

    As far as for my first build, I would like it to be jack of all trades gun. As far as range goes, optics I'm planning on are 1x-4x at most, or a red-dot. Within 200 yards basically.

    Hopefully that helps.

    <EDIT> after downzero's post and some of the other stuff I've seen, I'll pass on the 300. So lets leave it between the 6.5 and 5.56.


    Ok... That somewhat narrows it down.

    vette has you covered on optics
    downzero got you away from the 300 (downzero I dont recommend the 9mm Luger either lol)

    You are not going to be reloading in the immediate future.

    Now, one last question... or so I think

    Do you plan to hunt with it, in Indiana, or just punch paper and steel?


    If the answer is hunting... and you want to hunt deer.. then go 6.5 Grendel. If the answer is anything but that, then the only thing that makes sense $$ wise would be the .223/5.56.

    If you want to punch paper and do it cheap.. go .223/5.56. That is about the cheapest and most readily available round for an AR... besides the .22LR. Im not going there lol.
     
    Top Bottom