AR15 Question

[Mike-Mike]

OK, I have an older SP1 that has a large front pin hole. I have an upper that has a small pin hole. I purchased the conversion pin and it seems to function.

Now here is the problem. The pin is kind of offset. So depending on the position of the pin it affects operation. I can turn the pin and it seems to operate fine. Then if I break open the rifle and put it back together it seems like the bolt gets stuck in the tube from the collapsible until I re-adjust the pin.

Has anyone had this problem or is this normal??

Thanks,

--MIke

 

[vellnueve]

Bad pin?

Is it something you have to remove in order to make it work/not work?

 

[Mike-Mike]

Bad pin?

Is it something you have to remove in order to make it work/not work?

No, The pin is good, it just moves but I think there is suppose to be a little play in there.

I just called bushmaster and they said that I have to torque it in a certain direction after breaking open the rifle and the only way to avoid this is to install a set screw. I don't like the answer.

I would like to know if anyone has used this and if it ever locks up while firing. Bushmaster said it would not.

Thanks.

 

[vellnueve]

My dad had a SP1 with a Bushmaster XM177-style upper with a similar pin and never had a problem with it (until a bad batch of IMI ammo combined with a .22 conversion kit to lodge four bullets in the barrel)


(although that rifle has since reverted to its original configuration and the upper now resides on a RRA.)

 

[HangEmHigh]

Ive got the same pin with my Colt lower/Stag upper. Ive never run it to the problem you describe. I do wish the holes matched so I could do a quick take down

 

[Mike-Mike]

Thanks for the feedback. I'll try to torque it the way they told me and see if the problem comes back.

 

[Joe R.]

Daniel Defense makes ( or did make ) an AR upper with the Colt large hole front. It might be something to look into.

Joe R.

 

[Mike-Mike]

Daniel Defense makes ( or did make ) an AR upper with the Colt large hole front. It might be something to look into.

Joe R.

Thanks. I already got the upper but its good to know.

 

[PatMcD]

Did you put the rifle together and then put the pin in? Get the two halves together correctly, put the pin in, and tighten it down. It shouldn't move after that. That's the way I was told to put it together initially. There really should be only one position where that pin will align and allow the rifle to close together.