Caliber for an AR

Caliber for an AR

This is a discussion on Caliber for an AR within the Defensive Rifles & Shotgun Discussion forums, part of the Related Topics category; I'm going to build an AR, this will be a SHTF/HD rifle as well as hopefully something that's just fun to shoot. I know the ...

Page 1 of 2 12 LastLast
Results 1 to 15 of 21

Thread: Caliber for an AR

  1. #1
    Member Array Laser Sailor's Avatar
    Join Date
    Sep 2009
    Location
    Right Here
    Posts
    185

    Caliber for an AR

    I'm going to build an AR, this will be a SHTF/HD rifle as well as hopefully something that's just fun to shoot.

    I know the difference between 5.56 and .223 and I would go with a 556 chambering if I use the smaller caliber round.

    What I'm curious about it building an AR chambered in something bigger, like .308 (which is also 7.62x51 right?).

    Would I have to find a special lower or can I use one marked "multi" and build/buy a .308 upper?

    Also if I went that way could I build/buy another upper chambered in 5.56 and simply swap them out on a whim? What about .22lr?

    I know the 5.56 is a decent cartridge, but if I'm going to use it as a man/zombie stopper I'd prefer a bigger round. What do y'all think?
    MA2, USN

    When only cops have guns, it's called a "police state". Love your country, but never trust its government.
    -- Robert A. Heinlein.


  2. #2
    Senior Moderator
    Array HotGuns's Avatar
    Join Date
    Dec 2004
    Location
    Arkansas
    Posts
    15,140
    Negative.

    The .308 uses a longer lower receiver,a longer magazine and a larger bolt head.

    They are not interchangeable.
    I would rather stand against the cannons of the wicked than against the prayers of the righteous.


    AR. CHL Instr. 07/02 FFL
    Like custom guns and stuff? Check this out...
    http://bobbailey1959.wordpress.com/

  3. #3
    Member Array Laser Sailor's Avatar
    Join Date
    Sep 2009
    Location
    Right Here
    Posts
    185
    I kinda thought my idea might be too good/simple to be true.

    Oh well, no need to debate the merits of 5.56 vs .308

    Thanks for the quick answer!
    MA2, USN

    When only cops have guns, it's called a "police state". Love your country, but never trust its government.
    -- Robert A. Heinlein.

  4. #4
    Senior Moderator
    Array HotGuns's Avatar
    Join Date
    Dec 2004
    Location
    Arkansas
    Posts
    15,140
    One thing about the AR that makes is so cool...

    Any caliber top half can be used as long as the bolt head is the same size as the 223, or the round fits in the standard mag.

    There are several different calibers that fit this criteria.

    Also, with a few parts changed out of the lower and a caliber specific bolt, most pistol cartridges can work, the most common being the 9MM and the .45 ACP. The only thing that needs to-be done with the receiver is a magazine block that takes up the additional space.

    The .308 is a whole different game. Several hard hitting calibers can be had due to the longer case...its pretty much the same thing as the .223. With the 308 length lower you can get into some serious firepower.

    You just have to know the limitations of each platform.
    I would rather stand against the cannons of the wicked than against the prayers of the righteous.


    AR. CHL Instr. 07/02 FFL
    Like custom guns and stuff? Check this out...
    http://bobbailey1959.wordpress.com/

  5. #5
    BAC
    BAC is offline
    VIP Member Array BAC's Avatar
    Join Date
    May 2007
    Location
    Tampa, FL
    Posts
    2,292
    Oooh. HotGuns just reminded me (indirectly) of an experiment I had forgotten to write down involving an AR-10, the 7mm-08, the 162 gr A-Max, possibly the 150 gr tipped TSX, and more money than I currently have to spend. I need another job.


    -B
    RIP, Jeff Dorr: 1964 - July 17, 2009. You will be missed.


    Defensive Carry Search Tips


    Step 1 - Choose a subforum on right side under "Search in Forum(s)"
    Step 2 - Type general topic of interest in "Search by Keyword" textbox.
    Step 3 - Read results and refine/repeat as necessary.

  6. #6
    Member Array JohnHenry's Avatar
    Join Date
    Dec 2008
    Location
    Willis, TX
    Posts
    119
    You might look at some of the heavier rounds, like the 6.8 SPC and the recent 30 Remington AR. I haven't shot either, but the specs are nice, and they fit the smaller AR receiver.

    Of course, I spoke with a close friend who just came back from some...er, exploits in Afghanistan, and he was using an H&K in 556 (he's usually a sniper). He said the round did its job just fine on actual targets, and was impressed (and he's a bigger bore guy all the time).
    __________________________________
    Harley rider
    Kimber CDP II Compact, SA XD SC40, Ruger LCP

    Favorites: "If you can read this, thank a teacher. If you can read this in English, thank a soldier."
    Admiral Gary Roughead, CNO: "I never, ever, want to see my sailors or Marines in a fair fight."

  7. #7
    Senior Member Array Frogbones's Avatar
    Join Date
    Nov 2008
    Location
    Texas
    Posts
    967
    How 'bout build for the 6.8spc round....I find that round is available more than one thinks. Good round to boot!!!

    My next rifle will be that cal.


    Though...magazines aren't as prolific.

  8. #8
    VIP Member Array nedrgr21's Avatar
    Join Date
    Jun 2008
    Location
    Midwest
    Posts
    3,935
    Check out the 6.5 Grendel as well - fits on the .223 size lower.

  9. #9
    Senior Moderator
    Array HotGuns's Avatar
    Join Date
    Dec 2004
    Location
    Arkansas
    Posts
    15,140
    Quote Originally Posted by BAC View Post
    Oooh. HotGuns just reminded me (indirectly) of an experiment I had forgotten to write down involving an AR-10, the 7mm-08, the 162 gr A-Max, possibly the 150 gr tipped TSX, and more money than I currently have to spend. I need another job.


    -B


    Tell us about that. I see no reason why it couldnt work. I dont really see an advantage over the .308 though, excepy recoil will be almost no existant.
    I would rather stand against the cannons of the wicked than against the prayers of the righteous.


    AR. CHL Instr. 07/02 FFL
    Like custom guns and stuff? Check this out...
    http://bobbailey1959.wordpress.com/

  10. #10
    Distinguished Member Array Siafu's Avatar
    Join Date
    Jul 2008
    Location
    East Jahunga
    Posts
    1,424
    I am a big fan of the AR's modularity. I am looking forward to when Spikes Tactical introduces their new .308 lower in the next few months. I have purchased several rifles from them and the last time I spoke with Tom I was told I wouldn't be waiting too much longer for the .308 milled lowers they have been promising. Spikes has Seekins Precision in Idaho doing their milled lowers and milled uppers and they are just works of CNC art.

    If you are interested in other AR calibers I have them in 9mm, 5.56 and .22 and they are all a blast to shoot!

    The .22



    The 5.56 and the 9mm



    My GF told me to stop calling Spikes and building rifles or she's going to use one on me!

  11. #11
    BAC
    BAC is offline
    VIP Member Array BAC's Avatar
    Join Date
    May 2007
    Location
    Tampa, FL
    Posts
    2,292
    Quote Originally Posted by HotGuns View Post
    Tell us about that. I see no reason why it couldnt work. I dont really see an advantage over the .308 though, excepy recoil will be almost no existant.
    This, plus the high BC bullets and only requiring a new barrel is pretty much it for me.

    Mainly what I want is an easy-shooting, longer-ranged rifle in a caliber that won't beat up new/young shooters. An AR-10 carbine in 7mm-08 seems like it should work nicely. Another perk is that Magpul's now selling inexpensive, reliable .308 mags. Problem is I don't have is a .308 AR mag and 7mm bullets to see if the A-max, TTSX, or other VLD bullets would actually fit (lookin' for 2.820" max OAL...).

    Anywho, just thinking out loud.


    -B
    RIP, Jeff Dorr: 1964 - July 17, 2009. You will be missed.


    Defensive Carry Search Tips


    Step 1 - Choose a subforum on right side under "Search in Forum(s)"
    Step 2 - Type general topic of interest in "Search by Keyword" textbox.
    Step 3 - Read results and refine/repeat as necessary.

  12. #12
    Distinguished Member Array tangoseal's Avatar
    Join Date
    Feb 2009
    Location
    Near Hotlanta!!
    Posts
    1,340
    You want a .308 go and buy a Armalite AR10. They are awesome.
    "I believe that the right of the citizen to keep and bear arms must not be infringed if liberty in America is to survive." - Ronald Reagan

  13. #13
    sgb
    sgb is offline
    VIP Member Array sgb's Avatar
    Join Date
    Jan 2006
    Location
    You don't need to know
    Posts
    2,414
    If you want to be able to afford to shoot it stick with 5.56.
    "There is a secret pride in every human heart that revolts at tyranny. You may order and drive an individual, but you cannot make him respect you." William Hazlitt (1778 - 1830)

    Best Choices for Self Defense Ammunition

  14. #14
    Distinguished Member Array nutz4utwo's Avatar
    Join Date
    Nov 2007
    Location
    yes
    Posts
    1,644
    I think a first AR should be 5.56. There is elegance in the original AR design and I think many shooters are too quick to dismiss it.

    With a normal 5.56 upper and lower, a benefit (as you have pointed out) is you can swap out the bolt and mag and shoot .22lr out of it. (a conversion is $225 and a dedicated .22lr upper is more like $500) See my review:

    http://www.defensivecarry.com/vbulle...n-ar-15-a.html

    It is not the most ultra accurate precision unstoppable conversion, but it is highly functional, great for practice and training, and cheap to shoot!

    As of today, I would buy a CMMG "Bargin bin" rifle, a half dozen pmags, and a .22lr conv bolt...

    http://cmmginc.secure-mall.com/shop/...84734&cat=161&

    If you want to upgrade to something fancy and more expensive, it would be pretty easy to sell.
    "a reminder that no law can replace personal responsibility" - Bill Clinton 2010.

  15. #15
    VIP Member Array nedrgr21's Avatar
    Join Date
    Jun 2008
    Location
    Midwest
    Posts
    3,935
    Quote Originally Posted by BAC View Post
    This, plus the high BC bullets and only requiring a new barrel is pretty much it for me.

    Mainly what I want is an easy-shooting, longer-ranged rifle in a caliber that won't beat up new/young shooters.
    I'll repeat my suggestion for the Grendel - very easy shooting, in the same lighter/smaller rifle as .223, and it's longer range ballistics rival the .308. Can ya tell I really want one?

Page 1 of 2 12 LastLast

Sponsored Links

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

Similar Threads

  1. Which AR caliber?
    By Adkjoe in forum Defensive Rifles & Shotgun Discussion
    Replies: 7
    Last Post: August 20th, 2010, 07:03 PM
  2. Minimum Carry Caliber vs Primary Carry Caliber
    By Arisin Wind in forum Concealed Carry Issues & Discussions
    Replies: 23
    Last Post: October 18th, 2009, 12:52 PM
  3. which caliber
    By justherenow in forum Defensive Ammunition & Ballistics
    Replies: 3
    Last Post: October 25th, 2008, 06:29 PM
  4. 40 caliber versus 45 caliber for home defense?
    By Sneaky in forum Defensive Ammunition & Ballistics
    Replies: 24
    Last Post: January 11th, 2008, 01:24 PM
  5. Sig 229 -40 caliber verus Sig 239- 40 caliber
    By Sneaky in forum Defensive Carry Guns
    Replies: 30
    Last Post: December 8th, 2007, 10:48 AM

Search tags for this page

.225 vs .308 caliber

,

.225 vs 5.56 calibers

,

40 caliber ar rifles

,

7mm-08 162gr

,

ar ammo caliber popularity

,

ar caliber

,

can i make my seekins precision multi caliber lower into any size caliber does upper need to be changed

,

seekins precision chambered in 556 or 223

,

seekins precision upper only 223 or also 556?

,

selecting proper caliber ar rifle

,

spikes 6.8 multi zombie

,

the truth about 6.5 grendel

Click on a term to search for related topics.