7.62 ar question
10-28-2013, 03:56 AM
#2
Nontypical Buck
Join Date: Aug 2007
Location: WY
Posts: 2,056
NO!
The upper for a .308 AR is LONGER than the upper for a 5.56 AR. Say you were able to pin the two together at the forward pin:
1. How is a 5.56mm magazine going to stay inside a .308 magazine well?
2. What are you going to do to plug that gap between the rear of the 5.56mm upper and the buffer of the .308 lower? All those important parts like the hammer won't line up, either.
3. And worse, the bolt won't be under the influence of the buffer spring - therefore, will not properly return to battery even if you were able to get it to fire once. But with no pin to line up at the rear of the .5.56 upper and the .308 lower, that bolt will probably just fly out and into your eye on the first shot anyway.
Edit: Maybe you don't realize this, but the 5.56 AR can handle most cartridges up to the same length as a 5.56x45mm round (which is indicated by the LAST number: 45mm). That's why the 7.62x39 is offered in a 5.56mm-length rifle. Maybe you need to convince one of the many manufacturers that there's a market for a custom (longer) upper in 5.56mm for a .308 lower? Until then, the 5.56mm upper will always be too short to fit to a .308 lower.
The upper for a .308 AR is LONGER than the upper for a 5.56 AR. Say you were able to pin the two together at the forward pin:
1. How is a 5.56mm magazine going to stay inside a .308 magazine well?
2. What are you going to do to plug that gap between the rear of the 5.56mm upper and the buffer of the .308 lower? All those important parts like the hammer won't line up, either.
3. And worse, the bolt won't be under the influence of the buffer spring - therefore, will not properly return to battery even if you were able to get it to fire once. But with no pin to line up at the rear of the .5.56 upper and the .308 lower, that bolt will probably just fly out and into your eye on the first shot anyway.
Edit: Maybe you don't realize this, but the 5.56 AR can handle most cartridges up to the same length as a 5.56x45mm round (which is indicated by the LAST number: 45mm). That's why the 7.62x39 is offered in a 5.56mm-length rifle. Maybe you need to convince one of the many manufacturers that there's a market for a custom (longer) upper in 5.56mm for a .308 lower? Until then, the 5.56mm upper will always be too short to fit to a .308 lower.
Last edited by homers brother; 10-28-2013 at 04:01 AM.
10-28-2013, 05:18 AM
#3
Fork Horn
Join Date: Nov 2008
Location: Colorado Springs
Posts: 360
There is a special AR made, can't remember the name right off hand, that is convertible, the front part of the lower is pinned and can be swapped and work as an AR10. Think its called the Hydra or something like that. Can't remember who makes it though.
10-28-2013, 07:29 AM
#4
Nontypical Buck
Join Date: Oct 2009
Location: Kansas
Posts: 3,902
Simply put, no, you won't be happy with an AR-10 that converts down to 5.56. It has been done, and can be done, but you will spend far far more on that set up than you would have spent on an AR-15 and an AR-10. It's just not worth it to hybridize an AR-15/10
That said, there are certain rounds available for the AR-15 that you would be happy with for big game hunting.. .243wssm, .25wssm, 6.5 Grendel, .458socom, 6.8spc, etc
I'm not sure I'd be interested in a 7.62x39mm AR-15, there are better cartridges available.
That said, there are certain rounds available for the AR-15 that you would be happy with for big game hunting.. .243wssm, .25wssm, 6.5 Grendel, .458socom, 6.8spc, etc
I'm not sure I'd be interested in a 7.62x39mm AR-15, there are better cartridges available.
10-28-2013, 06:05 PM
#5
Giant Nontypical
Thread Starter
Join Date: Sep 2005
Posts: 6,867
I knew the 5.56 and 7.62x45 was the same and the 308 was longer. Just wondered if it had been done. I do see some benefits to it but not much outside of ammo cost. No i got little interest in a special converted ar10.
I like the excuse of i need another one cause ammos cheaper lmao
I figured the mag would be the easy part since they have 22 mags for them. Unless im mistaken cause arent there 22 kits to make a ar15 22cal
I like the excuse of i need another one cause ammos cheaper lmao
I figured the mag would be the easy part since they have 22 mags for them. Unless im mistaken cause arent there 22 kits to make a ar15 22cal
NO!
The upper for a .308 AR is LONGER than the upper for a 5.56 AR. Say you were able to pin the two together at the forward pin:
1. How is a 5.56mm magazine going to stay inside a .308 magazine well?
2. What are you going to do to plug that gap between the rear of the 5.56mm upper and the buffer of the .308 lower? All those important parts like the hammer won't line up, either.
3. And worse, the bolt won't be under the influence of the buffer spring - therefore, will not properly return to battery even if you were able to get it to fire once. But with no pin to line up at the rear of the .5.56 upper and the .308 lower, that bolt will probably just fly out and into your eye on the first shot anyway.
Edit: Maybe you don't realize this, but the 5.56 AR can handle most cartridges up to the same length as a 5.56x45mm round (which is indicated by the LAST number: 45mm). That's why the 7.62x39 is offered in a 5.56mm-length rifle. Maybe you need to convince one of the many manufacturers that there's a market for a custom (longer) upper in 5.56mm for a .308 lower? Until then, the 5.56mm upper will always be too short to fit to a .308 lower.
The upper for a .308 AR is LONGER than the upper for a 5.56 AR. Say you were able to pin the two together at the forward pin:
1. How is a 5.56mm magazine going to stay inside a .308 magazine well?
2. What are you going to do to plug that gap between the rear of the 5.56mm upper and the buffer of the .308 lower? All those important parts like the hammer won't line up, either.
3. And worse, the bolt won't be under the influence of the buffer spring - therefore, will not properly return to battery even if you were able to get it to fire once. But with no pin to line up at the rear of the .5.56 upper and the .308 lower, that bolt will probably just fly out and into your eye on the first shot anyway.
Edit: Maybe you don't realize this, but the 5.56 AR can handle most cartridges up to the same length as a 5.56x45mm round (which is indicated by the LAST number: 45mm). That's why the 7.62x39 is offered in a 5.56mm-length rifle. Maybe you need to convince one of the many manufacturers that there's a market for a custom (longer) upper in 5.56mm for a .308 lower? Until then, the 5.56mm upper will always be too short to fit to a .308 lower.
10-31-2013, 06:23 AM
#7
Nontypical Buck
Join Date: Sep 2005
Location: Indiana
Posts: 1,131
Simply put, no, you won't be happy with an AR-10 that converts down to 5.56. It has been done, and can be done, but you will spend far far more on that set up than you would have spent on an AR-15 and an AR-10. It's just not worth it to hybridize an AR-15/10
That said, there are certain rounds available for the AR-15 that you would be happy with for big game hunting.. .243wssm, .25wssm, 6.5 Grendel, .458socom, 6.8spc, etc
I'm not sure I'd be interested in a 7.62x39mm AR-15, there are better cartridges available.
That said, there are certain rounds available for the AR-15 that you would be happy with for big game hunting.. .243wssm, .25wssm, 6.5 Grendel, .458socom, 6.8spc, etc
I'm not sure I'd be interested in a 7.62x39mm AR-15, there are better cartridges available.
11-10-2013, 04:35 PM
#8
Spike
Join Date: Jul 2009
Location: Bedford, VA
Posts: 85
+1 for the 450B
Inside of 200 yds or so the 450B is hard to beat.. Factory Hornady ammo is available and under $30/box these days..
Sighted in correctly it is +/- 3" all the way out about 200 yds..
the 7.62x39 is more or less comparable to a .30-30 - not that there is nothing wrong with a 30-30..
Brian
Inside of 200 yds or so the 450B is hard to beat.. Factory Hornady ammo is available and under $30/box these days..
Sighted in correctly it is +/- 3" all the way out about 200 yds..
the 7.62x39 is more or less comparable to a .30-30 - not that there is nothing wrong with a 30-30..
Brian
11-10-2013, 07:29 PM
#9
Fork Horn
Join Date: Nov 2008
Location: Colorado Springs
Posts: 360
+1 for the 450B
Inside of 200 yds or so the 450B is hard to beat.. Factory Hornady ammo is available and under $30/box these days..
Sighted in correctly it is +/- 3" all the way out about 200 yds..
the 7.62x39 is more or less comparable to a .30-30 - not that there is nothing wrong with a 30-30..
Brian
Inside of 200 yds or so the 450B is hard to beat.. Factory Hornady ammo is available and under $30/box these days..
Sighted in correctly it is +/- 3" all the way out about 200 yds..
the 7.62x39 is more or less comparable to a .30-30 - not that there is nothing wrong with a 30-30..
Brian
