First of all, this is a great forum.  Glad to have found it.

I lurked here for a day or two, and then went shopping.  Found this pre Colt in really nice condition, and Bob's your uncle.  

I had wanted a heavy barrel, but can add one any time, so no big deal.  

?'s:

1 - What exactly is a Lightweight, other than a light barrel?  Other differences?  Is the lower any different than say a Match Colt, or a Bushie, etc?

2 - is it okay (legal) for me to use the 30rd mags that came with it?

3 - what is that "Colt box thing" parked inside my lower?  What does it do, can I remove it, and if so, how?

4 - My dad gave me an M1 carbine many years ago.  Sure, it has a quirk or two, but I am scary lethal with that rifle, just from lots of practice.  I notice, to my surprise, that the AR recoil is noticeably heavier than the M1.  This is with XM193 55gr ball ammo.  I'm not saying the recoil is heavy, just more than the M1.  How much of this is a function of barrel weight, etc?

5 - This thing looks stock, and my understanding is that I'm the 2nd owner, and that the first owner fired it 580 times total.  Any idea what year it was made?  Other than the normal fun stuff and customization, does the Sporter Lightweight have any known little issues or whatever that I should address first, or is it just another AR?

Thanks.  It's farkin cool to be in the AR nation!  I'm already thinking about getting another!  ;-)

http://www.tympanocentesis.com/ShopSite/media/AR-1.jpg

http://www.tympanocentesis.com/ShopSite/media/AR-2.jpg

http://www.tympanocentesis.com/ShopSite/media/AR-3.jpg

http://www.tympanocentesis.com/ShopSite/media/AR-4.jpg

Cool Colt!  Sorry I can't help with your Q&A, however Welcome to the Board!!  [coffee]

Welcome to the sickness...  Nice horsey.  I'll try to answer a few of your questions..
1) The lower should be pretty much standard... for a Colt that is...  Which is to say that some Colts have non-standard diameter pivot pin, and/or trigger/hammer pins.  Functionally just as good, but you have to be a bit pickier on what parts you can use in it.  See  http://www.biggerhammer.net/ar15/ for more info.
2) As long as the mags are preban (not marked with a date stamp after Sept 13, 1994 or LEO/Military Only) you are good to go.  See http://www.biggerhammer.net/ar15/magazines/rawlesfaq.html
3) It is a sear block, that Colt self-imposed upon themselves on some of their weapons (much like the possible pin size differences) to make it more difficult to install an auto sear.  It can be removed, but you wold have to deal with the hole in your receiver (above the selector switch).  I've no insight as to how you would remove it, if you chose to.
4) Don't know...
5) Colt could give you a manufacturing date.  I don't know of any oddities of running a Colt, other than the aforementioned pin sizes.

Hope this helps, and by no means is this all inclusive.  I'm no expert, and lurking around here is always an education for me.  Welcome again.

Brian

#4.

Unlike the M1-cabine, the AR-15/M-16 uses a weighted buffer to slow the cycle rate of the weapon.  What you feel as stronger recoil is in fact the weight of the buffer moving back into the receiver extension with the carrier and bolt, and the mass of all these parts being stopped by the end of the receiver extension.

The AR-15 just has more mass moving at cycle then the carbine, so you feel more movement, not sharper recoil. Think 1911 and the slide movement.  The 45ACP round doesn't really have that much recoil, it the big ass slide that is moving back that makes the pistol jump around.

Welcome to the board [wave] and nice looking Colt you have there. Good luck with it , don't forget to check-in on your Hometown Forum and say hello to your local members. Once again Welcome .

SaFe ShOoTiNg
 Jerry [):)]

Thanks for the replies so far, and for the link to biggerhammer.  Great site!

Dano - bingo!  It wasn't so much that recoil was sharper, the rifle just pushed more.  Thanks for the explanation.

I'll give Colt a call about the DOM.  FYI - I photoshopped the last two digits off the SN.  Did you mean that the SN 'range' was low, or just the number shown in the pic?

...more comments please on the sear block.  Legal issues involved in removal?  Suggestions for filling the hole left in the right side of receiver if removed?  Side effects of removal?

Thx agin.

OH yeah...

If this rifle is 95%, what's its ballpark fair market value?

With a SN that low, I would guess the rifle was built in the late 1980's. Probably 1988.

I think ???? that is when the name changed to "Sporter" and Colt started to remove the bayo lug.  (the first P.C. - AR)

But the rifle looks excellent.
I would keep the exsisting barrel, for semi auto its great, and a new Colt barrel would be quite expensive.