built my first AR today (lower build)

[mshootnit]

Well I traded off a rifle for a stripped armalite lower and an armalite upper that you don't usually see on a complete rifle. I bought an armalite parts kit and put it all together today. I had some concerns: when I tried the trigger function I wasn't sure the disconnector was flexing enough and seemed like there would be trigger slap. Then I was thinking damn I hope I used the right spring! I had a dummy round so I tried the trigger several times after putting it together and it seemed OK. My bolt catch seems to have some wiggle to it and seems like the spring is a little week but it does work OK I guess. Overall I think the rifle came together well and can't wait to shoot it. I wish I was around a real experienced armorer to look it over and give me an opinion on how well its put together and on the parts in general. I will get picks up when I get time.

 

[Quentin]

Well we're on the same wavelength, mshootnit - a month ago I built up a stripped ArmaLite lower with an ArmaLite LPK then married my ArmaLite upper to it. Mine turned out great and it sounds like yours did too. I really liked the LPK and how easy it was to install. Good quality, better than the Del-Ton LPK I used for my first lower. The bolt catch is a little different than ones in other kits but seems to work ok. It does feel a little different too.

Put up some pictures! I'll start with pictures of mine -

ArmaLite Stripped Lower:



ArmaLite Complete Lower with BCM receiver extension/M4 Stock:



Complete ArmaLite Rifle:

 

[mshootnit]

Quentin, that sight setup on yours is pretty cool. I don't have enough experience to put together something like that. I really liked the Stag 4 so I wanted to build a 20" rifle, and ended up with kind of an old school HBAR. Should be a shooter, and I can add optics if I want to later.

 

[Quentin]

Nice rifle, mshootnit! Thanks for the pictures. I love the look of a carry handle, too. I see you even have an ArmaLite carry handle so yours is more ArmaLite than mine. But neither of us has the white stamp on the front of the magwell that a factory assembled AR has.

Actually, my sights aren't that advanced - the rear sight is a cut carry handle, the front is standard Armalite and the RDS is a Bushnell TRS-25 that was on sale for $79 at Cabelas. Many would say the RDS is too cheap but it's cowitnessed with the irons so I could easily tell if its zero shifted. I used YHM rail risers to get the cowitness and can use the risers without the RDS and CH to drop on an old scope I have.

BTW, the cut carry handle is milspec height so it wouldn't zero with the ArmaLite front sight until I replaced the front sight post with a 0.04" taller post from Bushmaster. Cheap $6 fix so you might want to remember that if you ever go with a 3rd party BUIS since you'll likely have the same issue. Your current Armalite CH is the shorter commercial height so it works fine with the shorter front post.

Hope you enjoy your new AR!

 

[mshootnit]

I wasn't aware about the front sight height difference. Now my upper was said to have an A2 front sight. Is my carry handle correct for this setup? Here is my upper:
http://www.armalite.com/ItemForm.aspx?item=U15A4BA2&Category=bce7fa68-373e-4afc-b00e-63fe2c75d131

 

[Quentin]

Yes, your Armalite carry handle is the correct height for zeroing with the A2 front sight base on your upper since ArmaLite goes with the old A2 FSB height on its uppers instead of the Colt/milspec F-marked FSB height for flat fop receivers. Basically an A2 upper with the integrated carry handle should have an A2 FSB and a flat top (A4, sometimes called A3) upper should have the taller F-marked FSB.

Where you can get into trouble is when mixing the A2 FSB with a milspec carry handle or most third party rear sights, flip up, whatever. That's what I did and found I had to unscrew the front sight post too much to zero at 50 yards so I bought the Bushmaster 0.04" taller post which corrects the problem. It's a smart upgrade since it totally corrects the problem and is so darn cheap.

Again, you won't have to worry about all this unless you buy another rear sight (which you'd have to if you want a RDS). Odds are you'd have to go with milspec which probably would require the taller post. Bushmaster, DPMS and others also have this same issue and fortunately Bushmaster addressed the problem with the taller post.

By the way, if you later go with a milspec height you'd likely have the problem in reverse with your ArmaLite carry handle. But for free you could reindex the carry handle to zero properly with a tall front sight if necessary. You'd need to get it so the 6/3 is about 15 clicks above where the sight bottoms out. However this is a whole 'nother subject. If you want more reading on reindexing carry handles google Santose Improved Battlesight Zero...