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20'' or 24'' AR-10 Barrel Accuracy ??

 
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  #8  
Old 03-23-2013, 09:27 AM
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Re: 20'' or 24'' AR-10 Barrel Accuracy ??

Sorry guys for not giving enough Info.
I understand what yall are talking about now (I'm a little slow)

I have a DPMS. Oracle with a mediul weight 16'' barrel.
MY stock is a collapsable stock .
My buddys stock looks more like a rifle stock on a bolt gun.
My buddy has a DPMS.

I want to trade him barrel and stock but I would like to keep my brand new bolt . What would you guys do ? My friend says we can simply change complete uppers which is what I thought I would do but I like the idea of keeping my new bolt.
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  #9  
Old 03-23-2013, 09:48 AM
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Re: 20'' or 24'' AR-10 Barrel Accuracy ??

Quote:
Originally Posted by bigbuck View Post
Sorry guys for not giving enough Info.
I understand what yall are talking about now (I'm a little slow)

I have a DPMS. Oracle with a mediul weight 16'' barrel.
MY stock is a collapsable stock .
My buddys stock looks more like a rifle stock on a bolt gun.
My buddy has a DPMS.

I want to trade him barrel and stock but I would like to keep my brand new bolt . What would you guys do ? My friend says we can simply change complete uppers which is what I thought I would do but I like the idea of keeping my new bolt.
Call DPMS and ask about the bolt, they should be the same and that should be a non issue unless its a generational thing. The stock is an easy fix those parts can be swapped in about 20 min. I am not personal aware of any difference in the two rifles that would impede your swapping uppers. However ask DPMS on the phone.
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  #10  
Old 03-23-2013, 10:57 AM
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Re: 20'' or 24'' AR-10 Barrel Accuracy ??

Quote:
Originally Posted by ICANHITHIMMAN View Post
Call DPMS and ask about the bolt, they should be the same and that should be a non issue unless its a generational thing. The stock is an easy fix those parts can be swapped in about 20 min. I am not personal aware of any difference in the two rifles that would impede your swapping uppers. However ask DPMS on the phone.
Okay I will give them a call .
Thanks for the help and advice.
You mentioned earlier that I should keep the 16'' barrel I didnt think I could obtain the best MV for 1000 yards or 800 yards . I may be wrong but I thought the additional inches in barrel length would help . I guess what I want is a sniper type auto rifle. Is the weight the main reason you would stay with the 16'' barrel ? What lenght barrels is the military using on the SASS rifles ? Or Sniper rifle in the .308 AR configuration ? Do you know what grain bullet are they shooting ?
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  #11  
Old 03-23-2013, 01:21 PM
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Re: 20'' or 24'' AR-10 Barrel Accuracy ??

Quote:
Originally Posted by bigbuck View Post
Okay I will give them a call .
Thanks for the help and advice.
You mentioned earlier that I should keep the 16'' barrel I didnt think I could obtain the best MV for 1000 yards or 800 yards . I may be wrong but I thought the additional inches in barrel length would help . I guess what I want is a sniper type auto rifle. Is the weight the main reason you would stay with the 16'' barrel ? What lengh barrels is the military using on the SASS rifles ? Or Sniper rifle in the .308 AR configuration ? Do you know what grain bullet are they shooting ?
They use the Knights Armaments M110 here is a link, there are two versions. SASS is what the program was called to adopt a rifle (even though everyone new knights was already chosen). These rifles were not envisioned to provide precision fires past 800M. They were chosen for rapid engagements and compact handling in urban environments.

The standard match round for the M110/M14 is the LR118 round, It fires a 175g SMK behind R15 in LC brass (I believe they have now switch powders). The barrel length is not as key in the 308 as the twist rate and the bullet fired. I believe the general rule of thumb is 50 fps for every inch of barrel how ever the 308 is an exception.

The other precision fires platforms with in the military the M24 and M40 use a 24" barrel. However there was a program fielded a few years back by the marines in which 20" barreled versions were use with overwhelming success. The Army has chose to upgrade there M24 to 300 win mag and use the M110 for closer stuff.

If you want to use the search function over at M4c "KevinB" "sinister" are names to look for. Kevin is military sales rep for knights and sinister is a seal, with lots of hands on experience with these platforms. If you decide to join the forum be warned that they are not fond of certain companies and will openly ridicule anyone.

Its also important to note at this point that your rifle is not a bolt gun and has a floating firing pin. Whats this mean? when you close the bolt the firing pin actually impacts the primer, this can cause a out of battery detonation of your round destroying your weapon and maybe you. The military use a primer with a thicker cup to account for this (CCI #41). Next time you chamber a round extract it and look at the primer you will see a dent ,scary! Additionally as I mentioned in the beginning, your rifle is not a bolt gun. This means you have to be super careful with ammo selection NO SUPER PERFORMANCE AMMO, and when you reloading you need to reload for a gas gun that means not all powders are OK to use in your rifle just because they are in the manual for 308 Winchester.

God its so much info and I did not come by it all over night and this is by no means all of it, but I hope I'm helping some. Also I like short barrels 16" will get it done with the right bullet, I would never go longer than a 20". If you swap and find out you want a shorter one you can have it cut down, but then you will also need your gas port corrected or your rifle will not work there is also the possibility in that case you will need to swap buffer or spring, this is just FYI info.

Jon
Military | Weapons | Accessories | Knight's Armament Company

Also look through this and see if you can get any ideas.
http://www.m4carbine.net/showthread.php?t=65306
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If you want to shoot Bergers start here!
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  #12  
Old 03-23-2013, 01:32 PM
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Re: 20'' or 24'' AR-10 Barrel Accuracy ??

Quote:
Originally Posted by ICANHITHIMMAN View Post
They use the Knights Armaments M110 here is a link, there are two versions. SASS is what the program was called to adopt a rifle (even though everyone new knights was already chosen). These rifles were not envisioned to provide precision fires past 800M. They were chosen for rapid engagements and compact handling in urban environments.

The standard match round for the M110/M14 is the LR118 round, It fires a 175g SMK behind R15 in LC brass (I believe they have now switch powders). The barrel length is not as key in the 308 as the twist rate and the bullet fired. I believe the general rule of thumb is 50 fps for every inch of barrel how ever the 308 is an exception.

The other precision fires platforms with in the military the M24 and M40 use a 24" barrel. However there was a program fielded a few years back by the marines in which 20" barreled versions were use with overwhelming success. The Army has chose to upgrade there M24 to 300 win mag and use the M110 for closer stuff.

If you want to use the search function over at M4c "KevinB" "sinister" are names to look for. Kevin is military sales rep for knights and sinister is a seal, with lots of hands on experience with these platforms. If you decide to join the forum be warned that they are not fond of certain companies and will openly ridicule anyone.

Its also important to note at this point that your rifle is not a bolt gun and has a floating firing pin. Whats this mean? when you close the bolt the firing pin actually impacts the primer, this can cause a out of battery detonation of your round destroying your weapon and maybe you. The military use a primer with a thicker cup to account for this (CCI #41). Next time you chamber a round extract it and look at the primer you will see a dent ,scary! Additionally as I mentioned in the beginning, your rifle is not a bolt gun. This means you have to be super careful with ammo selection NO SUPER PERFORMANCE AMMO, and when you reloading you need to reload for a gas gun that means not all powders are OK to use in your rifle just because they are in the manual for 308 Winchester.

God its so much info and I did not come by it all over night and this is by no means all of it, but I hope I'm helping some. Also I like short barrels 16" will get it done with the right bullet, I would never go longer than a 20". If you swap and find out you want a shorter one you can have it cut down, but then you will also need your gas port corrected or your rifle will not work there is also the possibility in that case you will need to swap buffer or spring, this is just FYI info.

Jon
Military | Weapons | Accessories | Knight's Armament Company

Also look through this and see if you can get any ideas.
Precision Rifle - Semi-Auto PICTURE THREAD - M4Carbine.net Forums
Thanks for the links and Info .
I appreciate all of the knowledge you have shared this really helps .
I dont want to be a bother with too many questions but do you know what brand of powder the military used with the 175's or what powder should I purchase to use with my gas gun? Thanks
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  #13  
Old 03-23-2013, 02:40 PM
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Re: 20'' or 24'' AR-10 Barrel Accuracy ??

It used to be R15, I wrote it you just missed it.
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If you want to shoot Bergers start here!
http://www.longrangehunting.com/arti...accuracy-1.php
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  #14  
Old 03-23-2013, 06:13 PM
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Re: 20'' or 24'' AR-10 Barrel Accuracy ??

Quote:
Originally Posted by ICANHITHIMMAN View Post
It used to be R15, I wrote it you just missed it.
Ooops I'm going to send you a Pm in a moment.
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