Colt SP-1 question

[sumawolf]

I just picked up a Colt SP-1 and I would like to buy a carbine upper for it . I keep hearing the term large hole and small hole receivers or uppers . Does this SP-1 have what is referred to as small on both the pivot screw and the pivot latch ? What should I look for when buying a new upper for this SP-1 ?
Thanks much for feedback !

[jimtash]

I have an sp-1 also and it's a small hole upper. That means that most uppers sold today will fit it, so go ahead and buy any upper that you want to. Why Colt came out with the large hole upper I don't know.

[sumawolf]

Thanks for the info my friend

[vitiaz]

"Why Colt came out with the large hole upper I don't know"

So the "civilian" version was not the same as the "mil-spec" version. ..Can't have civvies running 'round with "mil-spec" firearms can we? :mad:

[eagle54]

Originally posted by sumawolf
I just picked up a Colt SP-1 and I would like to buy a carbine upper for it . I keep hearing the term large hole and small hole receivers or uppers . Does this SP-1 have what is referred to as small on both the pivot screw and the pivot latch ? What should I look for when buying a new upper for this SP-1 ?
Thanks much for feedback !
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hi Sumawolf

Colt SP1 has the large front pivot pin and the small rear pin ... to use a standard milspec small hole upper with the Colt SP1 Lower , you have to use a off set front pivot pin .. if you don't want to do that .. watch the boards - subguns.com ... ebay.com , ect.. for anyone selling a Colt large hole upper - with either the A1 or A2 rear sites, foward assist , brass deflector ... they are out there .. i know because i have them myself .. if you want i can take some pics of the uppers i am talking about ..this way you will know what your looking for ...

take care
eagle54

email is

eagle20@hvc.rr.com

[sumawolf]

Yes I sure would appreciate the pics . Like they say a picture is worth a thousand words . Jeff

[shamayim]

Originally posted by jimtash
I have an sp-1 also and it's a small hole upper. That means that most uppers sold today will fit it, so go ahead and buy any upper that you want to. Why Colt came out with the large hole upper I don't know.

Friend, if you have an SP1 with a small front hinge hole, you have the rarest Colt in existence. It's worth at least a million dollars, since no other SP1 in the entire production run had anything but a 5/16ths inch hole at the front of the lower, and the small hole unit is only 1/4th inch.

Either that, or you made a mistake in measuring the hole diameter;) .

Oh wait aminute. You posted that you had a small hole UPPER. Then it must be fitted to a large hole LOWER, with an adapter hinge pin. Yes, that's a possibility. Aftermarket uppers have been fitted to SP1 lowers for years w/that little aftermarket $5 part

Why did Colt put out a large hole upper? To fit the large hole lowers they were putting them on at the factory:D