I've got a chrome bolt/carrier cut for Forward Assist w/shrouded firing pin with the bolt marked MP.
gas key is chrome
extractor is chrome
ejector is chrome
gas key screws are "not" chrome but properly staked as COLT
Full circle & unmachined on the bottom for AR15/SP1 or SP2 (M16?)
The "chrome" is very dull as in matte finish.

When I was still "Uncle Sugar's property" almost all our issued M16s and XM177E1 weapons had slab side "chrome" carriers if my memory serves me right. I was told "my carrier" was only used in a short transitional period.

Anyone have any info that will confirm or negate this being an original Colt or H&R B/BC?
Any info is much appreciated.

I miss TWEAK! I hope your make'in out OK TWEAK!!!

Thanks to all!

INCIRLIK

Sounds like it's from an XM16E1.

Quoted:
Sounds like it's from an XM16E1.[/quote

Thanks for the reply.
I originaly had that thought and tried to run it down--but as you probaly know Colt has done many odd things and has "many" variations on the original Armalite design wth no clear-cut formula as to their production statistics.

Example--an HBAR flat-top w/buis in the '60s?  
A friend of mine has a transitional gun--SP2, slabside lower
A2 stock
A2 Barrel 1/7
A1 Flash Hider
A1 rear sight
A2 front sight
forward assist
no shell deflector
bayo lug
early pistol grip
round shiny handguards
.223 20 rnd. magazines
M16 F/A  Bolt/BC
Chrome Bore and Chamber

It Is New and Otherwise unfired except for the "proof-round."
Serial no# on lower says MFG 1978! (by COLT)
Dated on the original box reciept shipped late 1981 from Colt
The current owner and I picked it up from the Dealer together.
It is as though the "COLT" armorer ran out of "correct" parts and picked up whatever was available to assemble the rifle.

Anyway thanks for the info Sir.

INCIRLIK

Colt is (in)famous for using left over parts that the military doesn't use any more on civie AR15s, so hearing about late1970s/early 80s ARs with apparently non standard at the time pieces in them surprises me not at all.

Re the chromed, notched carrier; it's almost certainly a Colt piece.  Since it's unmarked, it would have been produced prior to the later contractor's involvement.  The GM/H&R contracts were precisely the reason Colt started putting the"C" on the stuff.

Sounds like a legit Colt's XM16E1 bolt group to me.  There are repros out there though.  There is one good clue you left out.  That is that 1960's carriers with the forward assist cuts have a large firing pin retainer hole on the right side.  Note the size of this hole on the top three carriers in this picture, and compare to yours, and the small hole on the later carriers below them:



Another detail is that the earliest carrier had full round carrier keys, rather then half round ones.  XM16E1 carriers come both ways (all half round in the above picture).  Very unlikely to find a full round carrier key on anything other then an original part.

BTW, never heard of a factory original H&R with chrome bolt group.

Thanks for the replies everyone. The amount and quality of information available and provided by the members of this board is astounding!

ELKIE, the carrier key is indeed round. Is there any disadvantage to using this bolt carrier group in my social stick as far as durability goes ?---I realize chrome is not Tactical but it sure is slick as far as the way it rides in the upper and cleans up after quite a few rounds .

Thanks to all!

INCIRLIK

I don't see any reason why you could not use that carrier, other then it does have collector value.  The bolts from that time frame are not made to the same standard as later ones though.

Quoted: I don't see any reason why you could not use that carrier, other then it does have collector value.  The bolts from that time frame are not made to the same standard as later ones though.

Well, I'm not into collecting but I was told the B/BC was probally worth much more than a standard B/BC--this was at a local funshow. Couln't care less so long as it gets the job done when my "ass" needs it. You say the bolts were note made to as high a standard as they are now? In what ways? I'm sure the specs. have changed through the years being it is a high stress component. Elkie, thanks for all the info and your time.

Regards,
INCIRLIK

Quoted: Quoted: I don't see any reason why you could not use that carrier, other then it does have collector value.  The bolts from that time frame are not made to the same standard as later ones though. Well, I'm not into collecting but I was told the B/BC was probally worth much more than a standard B/BC--this was at a local funshow. Couln't care less so long as it gets the job done when my "ass" needs it. You say the bolts were note made to as high a standard as they are now? In what ways? I'm sure the specs. have changed through the years being it is a high stress component. Elkie, thanks for all the info and your time. Regards, INCIRLIK

Around the same time that chrome was dropped from the bolt there was an upgrade.  Due to use of Ball powder the bolt steel was changed to Carpenter, and they were shot peened.

In addition a weep hole was added to the ejector spring, later chrome bolts have them though.

I shoot my old bolts, don't ever worry about it.  Have even used the old heavy firing pin (forgot to take it out).  Not saying it is a good idea, but there you go.