Hello there,

This is my first thread and I thought I would contribute my latest builds. I'm a BIG fan of A2 uppers and lightweight profile carbine barrels. I was getting tired of seeing the auctions get up above what I thought was reasonable for a worn, L.E.-trade carbine and decided to roll my own!

The Carbine on top is a Colt SP1 lower which I picked up cheap due to a nasty gouge on the receiver, that I had re-anodized by U.S. Anodizing to pre-ban Gray (great work, I might add!). The upper was snagged at a gunshow for a fantastic price in my mind, considering it's all Colt - including the Colt M16 BCG. It has the large pin, which is why I jumped on the SP1 lower. The before and after picture shows a cheap LPK that I installed initially to verify that everything was still in-spec after I received the lower back, though I was fairly confident in U.S. Anodizing's work.

The Carbine on bottom is a brand new Colt 6720, which I swapped the flat top upper out for a Colt-marked A2 upper I had won on an auction a few months ago, small pin and black anodizing. No M4 feedramps, so likely from an M16A2 - but it feeds and functions flawlessly with the M4 ramp barrel as expected. Sold the flat top upper and removable carry handle to a buddy of mine at work.

The only things that are not original Colt, are the M&A Car-15 stocks (which will be replaced with Colt N1 stocks this weekend pending their delivery), and the ALG trigger on the SP1 as it's my favorite shooter these days.

I'll shut up now, and let you all enjoy the pictures!

Very nice.

I did a similar build last year, but there is nothing Colt about it. I just like the configuration. BTW, it has a M1S CAR stock assembly. I really like these. The upper assembly is also M1S.

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I love it! You did a great job on it.

I think these are just the best all-around simple carbine you can get. Better sights than the A1, <6lbs and the small profile of the CAR stock and handguards make it a great rifle for shooters of all sizes.

You actually sprung for Colt stocks.  How much did they set you back?

That turned out really nice OP!  I love how you repurpose the SP1 lower so it looks just like the early 6520's.

I dug deep and paid a premium - $125 per, but one was never opened. Even looked through the clear plastic baggy it was packaged in to check for the "N" and "1" stamps. I'm probably leaving it in that bag for a rainy day and snagging another used one.

Thank you! I'm a sucker for the old gray anodizing, and that poor SP1 lower needed a new life. If I can win a decent condition stripped SP1 upper, with or without the forward assist, I might convert it to a SP1 carbine.

I just saved an old LE 6520 that's pretty rough, and plan on sending it to US Anodizing as well.  Just haven't decided if I want pre ban grey or black.  I'll probably start my own thread when I get it though.

Awesome!  I love mine - I started with an R6530 Colt Sporter Lightweight and swapped out the factory A2 stock.

I would do the gray, it just has that classic look to it! Victor did a great job on mine, would've been even better had I sent the upper to get the same application done.

You can't beat it! Did you get one of the M&A Car stocks, or a Colt N1?

Very nice.......

About five or six years ago, I was looking for a "truck gun" AR15, something I could beat on like a redheaded stepchild. I was keeping an eye out for a Maine-era Bushmaster. One day, I'm in my local gun shop and I see a used 6520 in the rack. It was a former LEO gun so it has some scratches on it, but nothing too gnarly. It even has the "Restricted" stamping. One odd thing is, it has a half moon carrier, but no sear block. Not a bad score for $800. I'll take a used Colt over a new Bushmaster most any day. It's become my preferred AR over my tricked out 6920.