First build help..matching upper & lower
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First build help..matching upper & lower

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Old 07-05-2013, 11:40 PM   #1
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Default First build help..matching upper & lower

I'm building my first AR...first of all, thanks to EVERYONE for all their input.
My question is, is there anything I while consider or any minor tweaking I may need to do if I'm going with a lower and an upper from different manufacturers? It's a BCM upper and a spikes lower. They're both 5.56.
I didn't think I'd have to worry about it, but I read something in another thread about maybe running into minor tweaks I'd have to do?
An I mislead or what?
Thanks again..
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Old 07-05-2013, 11:52 PM   #2
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About the only thing that you should run into is a slight difference in color between the upper and lower, it might bug you at first, but you don't even care after a while

There may also be a slight bit of wobble between the upper and lower, which again isn't that big of a deal, you can remedy that with a $3 accu-wedge. Don't worry about it, it isn't complicated, I doubt you'll have any issues.
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Old 07-05-2013, 11:53 PM   #3
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You SHOULD be fine. These parts are made within a standard set of tolerances. But there is no way for us to know until you physically have the 2 pieces and put them together. Plus you have 2 very reputable brands going into it. That always helps
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Old 07-06-2013, 12:52 AM   #4
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I am about to order/buy my upper, and the thought crossed my mind too. I was considering buying another manufactures upper... Rock River is really slow right now, so many orders... I guess, I could get something else, and eventually match an upper later, and then user the one I order for another build... I like that...
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Old 07-06-2013, 01:03 AM   #5
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This was just covered in an active thread. One of the best ways to learn is to read the treasure trove of info in this forum.
The biggest issue with assembling an AR isn't so much getting the parts together right - it's getting the right parts together.
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Old 07-08-2013, 11:51 PM   #6
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i ordered a del-ton lower and a PSA upper, i have an angle grinder, files, a dremel, sand paper, wire wheels, steel wool and a bench top grinder if i have any fitment issues LOL. i'm planning to duracoat them both so they match. i got an accu wedge just in case too
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