AR Sponsor
Posted: 4/16/2011 1:36:47 PM EDT
|
Please help me identify these uppers estimated years,models,ect.
rebated lug,no forge marking, faint square and triangle proofs 
large hole, CM forge, square and triangle proofs 
rebated lug,no forge markings,square and triangle proofs 
rebated lug,no forge markings,square and triangle proofs 
The bottom two have an excellent finish like new with no charging handle or bolt wear. They are just splotchy from breakleen degreaser residue and haven't been oiled. |
|
Numbers 1, 3, and 4 are round forge 604 upper receivers (I believe '67-'68 due to the counterbored front lugs). Number 2 is a later SP1 upper receiver. Note that the pivot pin hole is larger than the takedown pin hole, and if you look on the bottom near the rear lug, you'll notice that there is no auto sear cut. Also, the forging underneath the port door lines up with the lower receiver, which would only be found on SP1's and early M16 (601, 602, early 603, early 604) upper receivers.
ETA: They are all Colt. |
|
That's what I thought but it just said "late or early" on the flash hider.I'm assuming 67-68 kinda fell in the middle. I'm guessing a non trap door D stock also.
Do you think I could get away with a 3-prong FH on the SP1 upper (#2) since it has the early contour line up under the ejection port door? What barrels did they come with? |
| Tons of those 604's were arsenal re-finished and re-built. Not uncommon to see them with three prong FH's. Probably see more 604's with 3 prong's than birdcages in reality even though not period correct. Most the surplus 604's I've seen were a strange conglomerate of parts. See more parts correct retro's than I ever saw authentic period parts correct 604's. By my time in the 70's most had already been re-arsenaled. Non trap door D is also period correct and most I've seen were non trap even after re-arsenal. Looked to me like most re-arsenal's got a new barrel, new BCG with serrations and small hole on right and new HG's but 3 prong FH was retained and even if stock was replaced most I've seen were type D.. |
AR Sponsor