I just signed up and got online tonight.  I don't own an AR-15 and admittedly know very little about the numerous variations out there.  I've shot them; but that's it.

Many years ago (1989/90) I bought a lower receiver.  I've been working on my handgun collection for a bit and now want to get into more rifles (I only have 2).

The lower receiver has writing on:
CAL. 223-5.56
MOD: J-15
EA: (some stamped numbers - serial# I'm guessing)

E.A. CO. - what does this mean? Is that Essential Arms?
KR. SPR. LA. - what does this mean?
It has a rough gray finish. Normal?  Or do you guys recommend painting it black?

With all that aside, what would you recommend for a path to build one up?  I would like to keep the cost below $500.  I was thinking of an M4A3 upper.  Opinions?  16" barrel?  Heavy barrel?

And are there any companies that you recommend buying this stuff from?  Bushmaster?

Whether or not you decide to paint the lower probably depends upon you aesthetic sense, and whether you find an upper in a color which matches.

Most uppers these days tend to be black, so the color probably won't match -- if that bothers you but a can of Norells paint and a cheap airbrush and paint it to match the upper. Unless you absolutely know that you can't live with the missmatch, try assembling it first -its relatively easy to paint afterwards if you don't like the colors.

Bushmaster uppers are fine -- but you may find them a bit pricey if you want to keep to your budget.

Take a look at the uppers offered bt Del-Ton, they are very reasonably priced, they are good people to work with, and they have a nice variety to choose from.

essentialarms.com/ Link to the manufacturer of the lower.
Lot of kit companies out there. You just have to figure out what you want.

Are there any issues with missing the manufacturers (e.g., lower from one guy and upper from another)?

For barrels, I'd like more capability of shooting further away, which is why I was leaning toward 16" barrel.  For this type of gun, is a heavy barrel really offer a lot?

Barrel length really makes little difference to accuracy.

Where it does make a difference to is the velocity of the bullet. There are a few hundred fps differences between 14.5, 16 and 20 inch barrels. The higher the velocity, the better the effective range (in general).

The main advantage of the heavy barrel is that it heats up slower. As the barrel heats up it expands, the expansion has some effect on the zeroing of the sights. If you are going in for serious target shooting the heavy barrel is probably worth it -- but beware that it is heavy. If you are more interested in plinking, you will appreciate a lighter barrel -- especially if you end up carrying the gun far.

If you are interested in target shooting, my 2c worth would be to go for a 20" heavy barrel.

If you want a fun gun, then a lighter 16" barrel is probably the best compromise. Depending on how good a shooter you are, you may well not notice the difference between the two -- you need to be pretty good to shoot either of these configurations to the max of its capabilities.

Edit: mixing upper/lower: In general, no problem at all. If there is a problem one half or the other is out of spec. It happens, but rarely, and then even getting both halves from the same vendor is no guarantee of not having problems if one half it truely out of spec.

Great advice and thank you.  I'm already diving into the Del-ton website.  I'm a mechanical engineer which means putting one together will be incredibly challenging for me.  But I really look forward to it.

Take a look at J&T Distributing as well.

They have a good reputation and they are a board supporter in the Industry Section as well.

You also might want to think about getting one with a chrome-lined barrel. It will degrade accuracy a tad, but if you don't have a match trigger and expensive ammo, you'll never notice the difference and the barrel life will double and be easier to clean.

WIZZO

BTW, Welcome

Will do.  Thanks.

Why do they make a point of saying pre-ban vs. post-ban?  I thought the ban was lifted.

Quoted: Will do.  Thanks. Why do they make a point of saying pre-ban vs. post-ban?  I thought the ban was lifted.

It is lifted for most of the U.S.

Certain states have their individual AWBans that mirror the old Federal one. Therefore, they have the need for the post-ban stuff still.

WIZZO

Thanks.  Hopefully Georgia is not one of the ban states.  It really does make me want to vent about the 2nd ammendment and what it was really meant for and how the assault weapon ban violates it.  But I'll refrain, sort of.

Georgia is fine.

New York, 2 or 3 other New England states, California.....I think that's about it.

Down South is good to go.

WIZZO

Quoted: Georgia is fine. New York, 2 or 3 other New England states, California.....I think that's about it. Down South is good to go. WIZZO

CT Still Carry's the Federal Ban-------------------------------