Colt Forum banner

1 - 20 of 25 Posts

Premium Member
Joined
524 Posts
Discussion Starter #1
Did the SP1 always have a trapdoor stock for a cleaning kit or did the early ones just have a rubber recoil pad ?
 

Registered
Joined
647 Posts
In the 3rd AD in Germany, we were issued stocks with traps to replace the ones without in the fall of 1972. I don't know when commercial ARs made the change. All the M16s I saw in Viet Nam in 1969 and 1970 were still the early trapless stocks as were all the ones we had in the training center at Fort Campbell 1971.
 

Registered
Joined
2,771 Posts
The trapdoor buttstock and birdcage FH on the "later version" model R6000 SP1 should roughly coincide.
The 1969-70-71 mentioned timeframes sound reasonable.
Some with mixed features would not surprise me.
 

Registered
Joined
9,291 Posts
I wouldn't be surprised that when the military began specifying the trap-door stock Colt simply continued to use up the solid butt pad on civilian AR-15 production until inventory ran out then converted to the same the military was using. It makes sense to do so and we know Colt never really threw anything away when it was still usable otherwise.
 

Registered
Joined
17 Posts
There would have been a transition period with new components going to the military first. There was a war going on. Somebody already said it. Colt never wasted anything.
 

Registered
Joined
54 Posts
Mine SP1 from 1974 has it (storage box) and the birdcage flash hider. If two 1971 above don't have it, it could have started around 1972-74 time frame.
 

Registered
Joined
17 Posts
I read that M16's started to get the trap door stocks around 1971. I imagine AR15's wouldn't get them until much later.
 

Registered
Joined
335 Posts
I have a SP1 from 1971 and it has the rubber butt pad and the three prong flash hider. I bought it from the original owner and he didn't change anything on it.

My '71 SP1 has the birdcage FH, and this is the first one I have seen with the 3-prong FH that is later than 1969. Another case of Colt using up older available parts, which does makes $$$ sense.
 

Registered
Joined
25 Posts
Berkeley 492, Very nice - looks minty - and I'm interested to see this! Thank you. So you have an original 71 sp1 with a three-prong flash hider and and a type D butt stock. May I ask, what are the barrel markings and is there a knurled crush washer or a lock ring with wrench flats holding the flash hider in place?
 

Premium Member
Joined
170 Posts
Here are a few pictures of my 1971 SP1 posted above showing the barrel marking, the flashhider and lock washer and the butt stock. The lock washer appears to be very lightly knurled. I don't think I've ever seen an original 3 prong flash hider that had wrench flats. There is a special wrench slotted for the 3 prong flash hider that is used to remove and replace the flash hider.








Here's a picture of the barrel markings on my M16A1 upper assembly. The lock washer is knurled, barrel marking is different and the A1 flash hider has wrench flats.
 

Registered
Joined
1,019 Posts
My very first Colt SP1 I bought brand new in 1971 (about Spring - Summer time) had the rubber butt pad, no trap door and it had the A1 birdcage flash suppressor.

I bought it for around $200, it was an excellent rifle, I used it for about 13 years then sold it and bought the new '84 model Colt AR-15A2 Sporter II rifle.
 

Registered
Joined
25 Posts
Does anybody know about the barrel markings for '69 or '70 SP1's? Would "MP" and just "C" with no "B" mean the barrels with chromed chambers but unchromed bores?

I think the chromed chamber started in about 1967 for the M16's and then switched to C MP C. By 1969 the M16's were getting the C MP B barrels with chromed bore. That would follow what is being described here, using up outdated M16 components on the SP1.

Anyone know for sure?
 
1 - 20 of 25 Posts
Top