SP1 upper with large pin on an A2 lower?

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[ARCHIVED THREAD] - SP1 upper with large pin on an A2 lower?

Posted: 11/27/2018 11:41:40 PM EDT

Bushing maybe? Anyone mate these two together somehow?

Posted: 11/28/2018 12:03:29 AM EDT

[#1]

Welcome and, yes, there is a bushing available. It has been done.

Posted: 11/28/2018 12:05:09 AM EDT

[#2]

Example : https://www.eabco.net/Colt-AR15M16-Receiver-Offset-Adaptor-Pin_p_15090.html

Posted: 11/28/2018 12:18:14 AM EDT

[#3]

Yep, did that on my fathers clonish rifle I built him. Once you get the bushing clocked right a drop or two of gorilla glue / super glue and you're good to go. It's just to keep the bushing from rotating when you separate the receivers. Otherwise it can be a pain to get the holes to line up. And this way it's not permanent should you get a retro lower.

Never seen an offset pin like posted above before. Just used an offset bushing.

Posted: 11/28/2018 10:34:25 AM EDT

[#4]

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Quoted:
Never seen an offset pin like posted above before. Just used an offset bushing.

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Offset pin is for reverse case of small hole upper on big hole lower.

Posted: 1/6/2019 12:12:13 PM EDT

[#5]

I Found the offset bushing. Curious as to why these are offset. Seems like maybe to guarantee fit to many types of upper/lowers?

Posted: 1/6/2019 1:26:08 PM EDT

[#6]

Quote History

Quoted:
I Found the offset bushing. Curious as to why these are offset. Seems like maybe to guarantee fit to many types of upper/lowers?

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The big pin holes are offset forward of the centerline location of the small pin holes. If the holes were on the same centerline you could just use a straight bushing or sleeve, but the holes are offset relative to each other, requiring the offset bushing.

Posted: 1/10/2019 9:58:33 PM EDT

[#7]

Quote History

Quoted:

Offset pin is for reverse case of small hole upper on big hole lower.

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This.

[ARCHIVED THREAD] - SP1 upper with large pin on an A2 lower?

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