Hello everyone, I've been lurking in this forum for a while and decided that the time was right for me to get a retro AR15.  I thought about building one, but I came across a clone of the Colt 603 on the EE here instead.  Negotiations were held between myself and the seller and today, it arrived! The rifle is very nice and I'm glad to finally have my own representation of an M16A1 to go with the A2 I built a few years ago.  Pics will surely follow!

My questions concern the bolt carrier and flash hider.  The rifle currently has a reproduction 3-prong FH and I kind of like it; I've never seen one in person nor had a rifle with it before.  From what I can find online, it seems that it should actually have a birdcage FH.  The lower is an A2 with full magazine well fencing that was reprofiled to A1 specs; this fencing is what really makes it a 603 to me.  However, would it have been possible to have a 603 with full fencing and a 3-prong FH?

Secondly, the bolt carrier...right now, it has a new production phosphate BCG...I have always liked the look of a chrome bolt carrier in a retro AR.  Would it have been possible to have a chrome BCG in a 603?  If so, anyone have a used one they want to trade for a PSA BCG>

Thanks everyone!

Congrats on your new retro. As far as the FH and BCG goes, I have seen photos of M16A1s with 3-prong FHs in Vietnam, but not many. Colt was infamous for using parts from other models. The BCG in the A1 is phosphate-coated. They did not have chrome BCGs. Some of the earlier models did. Personally, I would rather have a birdcage FH on the A1. It does look more correct for the most part. It is up to you.

The "603" nomenclature covers an extended period of Colt AR production featuring a forward assist.  The earliest 603s (XM16E1) has completely different features than the later 603s (M16A1).  What's "right" or "wrong" on your rifle depends on what year you're trying to replicate.

The partial fence lower and 3-prong FH (a damned sexy combination) point to an earlier build--particularly if they're accompanied by a chromed BCG.  (Unfortunately, an original E1 BCG is a rare and expensive near-unicorn so you might want to use a modern version.)

There were many more A1s (full fence, birdcage, park's BCG) than E1s, so the parts are easier to find..."easy" being a relative term.

What other clues to "era" does your rifle give?  Can you post a photo of the upper receiver?  What's the barrel marking?  Does it have a type D stock, or Type E (with trap door)?

It has a full fence lower and the stock has the trap door and drain hole in the screw.  I'm thinking that maybe I'll just leave it as-is since I like the 3 prong and leave the BCG alone.  I'm not after replicating a particular year of production; just wanted a clone of an A1 and got it

You know, if you've been lurking here a while, you should understand the basic rules.  We like photos!  Even if it's "just another A1."

Maybe these will work...taken from the EE ad since I haven't had time to take any pics this weekend.  I did manage to fire a few through it, and it's pretty accurate and shoots very well!

I wasn't aware of Anderson turning out A1 lowers.  When did I miss that?

It was reprofiled by the seller to match A1 specs.  He did a fabulous job with it.  I was thinking about finding an Armalite lower and switching everything over to it, but after seeing how nice this one is combined with the nice finish, I'm gonna leave it alone

Someone did an excellent job converting that lower to A1 spec.

Nice gun, welcome to the addiction

Thank you! I do have a question...my stock and pistol grip have some brown "stuff" on them, and my research leads me to believe it's "mottling"?  What is that, and how can I fix it?  Part of me just says screw it and leave it as-is, but I guess no harm in asking how to rectfy it in case I choose to!

Fix it? Some people pay extra for that

Personal preference, I'm sure you could find someone to trade with if you don't like it.

There is no fixing it as far as I know. I actually really like stocks and grips with heavy Mottling . You can always rub oil on your stock to make it look darker.

There ain't nothing like a 603

Yeah! That furniture looks great as is--don't mess with it!
And I agree--someone did a nice job reprofiling that lower.
Overall, it's a great-looking rifle.  I'm sure you'll enjoy her!

But since you seem to be interested in getting things reasonably "right," let me point out a few minor things:

The selector switch has a "tic" on the right side.  The A1 would have come with a no-tick selector.
The ejection port door is too modern.  It should have a flat rectangle pad.
And it looks like the buffer tube is gloss black instead of the retro gray.

If you're determined to change things on the rifle, those are reasonably easy things to "fix," over time, without breaking the bank--and you'll probably find them very satisfying changes!

But even as is, you've got a nice retro rifle there!

Thanks everyone; I really do enjoy this rifle and am glad that I can finally post here without feeling like an outsider with my A2 (that one I built myself from a bunch of parts a few years ago).  I had intended on building my A1, but I did a lot of research and couldn't buy the parts for what I have in purchasing this one.  Plus, my costs were figured using a common A2 lower, and I'm not even going to pretend that I can reprofile one like this one is I will consider making the small changes such as the no tick selector and painting my buffer tube (or at least what is seen) something a more correct color.  I'll also do the port door if it's possible to swap it without pulling the barrel to get the hinge rod out.  

And as for my furniture, I'm going to leave it.  With how much I shoot this rifle and take it with me, the metal will have a BTDT look soon.  However, for the small parts mentioned above...anyone have a source?

OP: Looks pretty good for your first build. Great job. My years on active duty U.S.M.C. 1978-82, our main rifle was the M16A1. I'd like to note that at least 10-20% of all A1's still had the 3 prong FH. So I wouldn't give it much thought leaving it on.

Going through Basic Training at Ft Jackson in 1984, we still had A1's--a mix of Colt, H & R and GM.  About 50%-60% of our A1's had chrome BCG's. My Colt M16A1 (ser #1063446 thank you MSGT Merrero) had a chrome BCG and when we got rained on during our 15-mile-march, the next day all the parkerized BCG's were frozen and had to be mortared a few times to break them free of the overnight rust (we were on b ITT/Bivouac overnight) in order to do inspection arms.

The A1s I used in the Marine Corps in the late 1970s and early 1980s all have A1 FHs and phosphate-coated BCGs.

Congrats!  Nice rifle, you will love it.  It is so much more fun to shot than an M4gery with a bunch of tacticool stuff on it.

603's with 3 prongs are sexy. Fact.

Very cool rifle.  I now want a scope.

I did go out and shoot it 2 Sundays ago, just been very busy and not able to report back.  It shoots wonderfully and is a joy to handle since it's so light.  I can't wait to see the WTF looks on some of the local range patrons' faces when we are there at the same time, them shooting tacticool budget carbines and missing the target while I nail it every time with this 603 (it's pretty damned accurate, BTW)

Can you reach out to the person you purchased it from and ask them who did the machine work on the lower to get the A1 profile?

The seller did the machining himself I believe if I understood the ad correctly.  I bought it off the EE here and I'm not sure if I can share his name or not

Oh, that rifle looks familiar...

the reprofiling is this guy's fault

Nice work sir!