RRA lower: What Uppers for reliability?

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[ARCHIVED THREAD] - RRA lower: What Uppers for reliability?

Posted: 1/9/2006 1:38:55 PM EDT

Hi, I'm working on my first AR build and am trying to figure out what I want to put on my RRA stripped lower. First off is the upper. I was hoping for a 14.5" RRA upper but they don't make em (I believe). Only big name I can find is Bushy. I may just go with a RRA 16" upper but am thinking about putting on a 14.5" Bushy. Any reliability or mix and match issues with these configs? Thanks for any help.

Posted: 1/9/2006 2:41:21 PM EDT

[#1]

Mixing and matching between RRA and Bushmaster won't pose a problem. Be sure that you know what you are doing if you want to go w/a barrel shorter than 16" though since they become subject to NFA regulations. You can go with a barrel shorter than 16" if you include a permantly attached muzzle device (such as a flash supresser or muzzle break). Also be sure to check your local state laws. Ug, too many laws...

Read this for more information on the legalities of an SBR (short barreled rifle).

Posted: 1/9/2006 2:43:48 PM EDT

[#2]

I've got an Oly, RRA and Bushy upper. Never had any problems with any of them.

You will have to have a min. fixed barrel length of 16" unless you are going to register your receiver as an SBR. The 14.5" barrels generally have a 1.5" muzzle device permanently attached.

Posted: 1/9/2006 3:45:26 PM EDT

[#3]

First, thanks for replying. Reliability is number one for me. I don't care about the color not matching but just like functionability and the such. What I'm going for is 16" oal and from what I understand, the RRA barrels will be 16" plus the flash hider. Is that right? That's why I'm going for the 14.5" or 14.7" barrells out there. Any more thoughts on the subject? Thanks again.

Posted: 1/9/2006 4:31:37 PM EDT

[#4]

Quoted:
Hi, I'm working on my first AR build and am trying to figure out what I want to put on my RRA stripped lower. First off is the upper. I was hoping for a 14.5" RRA upper but they don't make em (I believe). Only big name I can find is Bushy. I may just go with a RRA 16" upper but am thinking about putting on a 14.5" Bushy. Any reliability or mix and match issues with these configs? Thanks for any help.

I have had many RRA Lower/Bushmaster Upper problems. RRA rear lug area radius cut in the lower is extremely tight when matched with a Bushmaster Upper. Frequently you have to file the rear lug on the Bushmaster Upper Receiver, this is the small retangluar/square lug on the bottom rear where the rear take down pin goes through. You may have to file both rear vertical corners and the bottom corners.

Posted: 2/3/2006 9:14:22 AM EDT

[#5]

Quoted:
I have had many RRA Lower/Bushmaster Upper problems. .

and then :

Mixing and matching between RRA and Bushmaster won't pose a problem

I am thinking of buying a RRA lower but I'm not too thrill about filing my Bushmaster upper to make it fit.

How many of you do/ do not have problem with the fit?

Posted: 2/3/2006 1:52:24 PM EDT

[#6]

recievers are contracted out.

initially they are tight fitting but eventually work itself together. dont get the reason everyone cries about tight reciever and when they get loose one they cry as well.

a bushmaster finished upper reciever would have about the same problem as any other.

the problem is the higher than normal shelf in the rra lower.

Posted: 2/3/2006 4:10:14 PM EDT

[#7]

Quoted:
recievers are contracted out.

initially they are tight fitting but eventually work itself together. dont get the reason everyone cries about tight reciever and when they get loose one they cry as well. a bushmaster finished upper reciever would have about the same problem as any other.

the problem is the higher than normal shelf in the rra lower.

Actually, I'm talking about more than a tight fit. I have had many that did not fit. It wasn't caused by the shelf, but the radius cut not being cut far enough back. It was common for me in a RRA lower, Bushmaster upper combination. The two uppers would not close far enough for the rear take down pin to go through.

Posted: 2/3/2006 4:11:06 PM EDT

[#8]

Quoted:
recievers are contracted out.

initially they are tight fitting but eventually work itself together. dont get the reason everyone cries about tight reciever and when they get loose one they cry as well. a bushmaster finished upper reciever would have about the same problem as any other.

the problem is the higher than normal shelf in the rra lower.

Actually, I'm talking about more than a tight fit. I have had many that did not fit. It wasn't caused by the shelf, but the radius cut not being cut far enough back. It was common for me in a RRA lower, Bushmaster upper combination. The two uppers would not close far enough for the rear take down pin to go through.

[ARCHIVED THREAD] - RRA lower: What Uppers for reliability?

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