Interest in "retro" AR15s.

[cuervo]

If you could live with an A1 forgery instead of an SP1, you could use your own lower and buy an almost-complete A1 upper from CDNN.
http://cdnn.stores.yahoo.net/arsp1upnewco.html

They say these are SP1 uppers, but since they have a forward assist and are small hole, they are really A1 uppers.

The differences between the original SP1, A1, and newer A2 lowers are pretty small. The only ones I can think of are:
1. the length of the stock, which most people wouldn't notice,
2. the butt piece on the end of the stock, and
3. a fence around the mag release

The only significant difference would be that non-SP1 lowers are going to be small hole; but since the CDNN upper is small hole, it would work with newer lowers without an adaptor pin.

Finding a true SP1 would be pricey, figure at least $1000.

 

[Detritus]

I'm looking for triangle handguards, anyone know where to get a set?

got mine from Northridge

But be aware that they tend to follow a order filling and shipping system that sems to be them asking each other "wanna pull some orders today, or play poker" :banghead:

but they were the only place i was able to find a decent set for a good price, and in stock instead of havign to beat the bushes for it.

 

[lightweight]

 

[DrDeFab]

NOS Colt A1 Uppers & buttstocks
DPMS Lower & B/BC/CH
$550 each

Fine rifles.

The only drawback is that while the 1:12 twist works for M193, M855 is tumbling by 50 yards.

 

[Wes Janson]

Question: I have a recent-manufacture semi-auto lower, what would I need to do in order to fit one of CDNN/Sarco's M16A1 uppers to it? Are there any significant non-cosmetic differences between one of the Sarco uppers, and a standard current production upper?

 

[Detritus]

I have a recent-manufacture semi-auto lower, what would I need to do in order to fit one of CDNN/Sarco's M16A1 uppers to it?

other than needing to supply a bolt/bolt carrier group and charging handle (these are missing on the sarco units b/c the ATF considers the bolt carrier assemblies to be a "machine gun part") the only thing you'd have to do is set it in place and push the pins in.

Are there any significant non-cosmetic differences between one of the Sarco uppers, and a standard current production upper?

a 1in12 "pencil" barrel it's lighter weight than pretty much all current non custom 20" barrels, but the 1in12 won't stabilize a bullet over 55gr. so you can't use the current crop of fairly cheap surplus 5.56 NATO ammo (beyond 50 yards or so).
lack of a shell deflector (though you may consider this cosmetic)

only other thing IS a cosmetic difference, most will probably be close to the so called "colt gray" color and not quite match a modern lower which will usua;;y be pretty much black.

 

[rangerruck]

collectors firearms in Housotn has a sp1 ar 16 with 3 prong flash, no forward assist, triangle handguards for 1300 bucks. but i noticed that it has instead of pushpens at the front takedown hinge, they look like large flatblade , screw types. is this correct? does any bodly else have any tips to look for , little lettering or mods and the like to make sure im really looking at an old one?

 

[Wes Janson]

On http://cdnn.stores.yahoo.net/arsp1upnewco.html it's showing a price of $369.99 for a complete upper minus the bolt/bolt carrier/charging handle.

On http://www.sarcoinc.com/m16.html they're offering a complete upper minus "bolt carrier assembly and cocking handle" for $275, +$10 for special select.

Is there any appreciable difference between these two, or is CDNN overcharging? Right now I've got a lower reciever and lower parts kit, so all I'm needing is the upper and a stock. What is the difference between a small hole and a normal hole? And how does one go about adapting a small-hole upper to a normal lower? Thanks!

 

[kentucky_smith]

Thanks Detritus, 19 bucks for the entire stock set is well worth a little waiting. I'm gonna make my A3 Doublestar a faux A1.

 

[cuervo]

collectors firearms in Housotn has a sp1 ar 16 with 3 prong flash, no forward assist, triangle handguards for 1300 bucks. but i noticed that it has instead of pushpens at the front takedown hinge, they look like large flatblade , screw types. is this correct? does any bodly else have any tips to look for , little lettering or mods and the like to make sure im really looking at an old one?

The three-prong was the original flash supressor style which tended to snag on things, so was replaced. This would indicate an older rifle most likely, but I cringe at the thought of spending $1300 on an AR15.

AR15.com used to have (and maybe still does someplace) a serial number page listing ranges of Colt s/n by production year.

The screw up front is correct for Colt, and it is a large hole, so would not be compatible with most uppers without an adaptor pin. The bbl should have CMP on it, indicating "Colt magnetic particle," aka magnaflux, for barrel testing.

 

[Henry455]

Rangerruck,

This is what it should look like:

 

[DMK]

On http://cdnn.stores.yahoo.net/arsp1upnewco.html it's showing a price of $369.99 for a complete upper minus the bolt/bolt carrier/charging handle.

On http://www.sarcoinc.com/m16.html they're offering a complete upper minus "bolt carrier assembly and cocking handle" for $275, +$10 for special select.

Is there any appreciable difference between these two, or is CDNN overcharging? Right now I've got a lower reciever and lower parts kit, so all I'm needing is the upper and a stock. What is the difference between a small hole and a normal hole? And how does one go about adapting a small-hole upper to a normal lower? Thanks!

SARCO's description is a little vague (maybe someone here has one and can comment, mine came from CDNN). They may not be exactly the same thing, but if it were me, I'd save the $100 difference and go with SARCO (although CDNN is much better to do business with, that's a big difference in price and I've never heard of anybody getting screwed by SARCO, I certainly haven't).

I think the cool thing about the SARCO upper is they charge you extra $25 for Colt handpick. I'm not sure who else made those older M16 uppers (way before FN got involved I believe), but personally, I think it would be really cool to get a GM Hydromatic.

As far as small hole/ large hole. The large hole is a Colt proprietary thing. If it's a small hole upper, it will fit any other AR15 lower and some Colts.

 

[rangerruck]

henry 455, thanks for that info. yes it does look like that, and that is the screw. also it does say sp1, what does that mean? Should it also say colt ar 15?anybody else out there with some old school tips to look for?

 

[Wes Janson]

Where does one get the adaptor to go from large to small hole?

 

[cuervo]

I think "SP" was just Colt's prefix for "sporter," which is how they tried to market the rifle.

IIRC, all Colt AR15s will be an SP model, either 1 or 2. When you get into the SP2s, you run into different color box nomenclature to distinguish them. (I was never able to keep all of them straight.) Even though SPs existed preban, Colt felt the bayo lug was bad so left them off, but kept the flash suppressor.


And, IIRC, Colt switched to small hole as well for their civilian market.

Offset pins are available from Bushmaster:
http://www.bushmaster.com/shopping/lowers/
You can also replace the big double screw with a large push-pin, but make sure the ball bearing moves freely before tapping it into the receiver.

Here is some other general info:
http://www.ar15.com/content/legal/serialNumberList.html
http://www.ar15.com/content/articles/history/evolution.html
http://www.ar15.com/content/products/barrels/twist.html