So i just finished assemblying a cali legal fab-10, with an upper receiver.
Butt stocks, on, everythings good to go....

Until i try pushing in the take down pin..
and it will NOT go through...

I tried lubing it with some clp to get it working, tried jiggling the upper around, and the pin will not go through.,.

any harmless ideas?suggestions?

thanks

Harmless as it gets.   If you have not already tryed, see if the pin will pass through the upper without the lower. If so then eyeball the holes for correct alinement. You did not give much info, so its a little hard to guess up on the correct answer to your problem. Maybe next time you can give a little history. But I hope this helps

Sorry
I was a little irritated while typing the first post...

Yea, the pin goes through great if i just placed it in the upper only...

If i took out the pivot pin, and tried pushing in the take down pin, it goes through like butter. But then the pivot pin does not want to go in...
and vice versa

Its definitely miss-alignment, and now I'm stuck on what to do about it.
If this was a regular ar-15, it wouldn't bother me all THAT much that i could just shove the pin in with a rubber mallet, but this is a fab-10 lower, which means in order to reload the non-detachable mag, i have to open up the receivers...

ARGH!!!

thanks ybh

Weelllll, You could move to ALABAMA "A GUNNERS STATE" LOL

Either the upper or the lower is out of spec.  Can you try another upper?

There is a lower blueprint PDF on this site, you can get the dimension and measure your receivers.

If you go to an undersized pin, or file the holes, you will have more rapid wear due to the loading routine.

I had the same problem with my FAB 10 and a BM upper.  I simply ground a very little amount of metal out of the bottom of the loop on the BM upper using a dremel and a carbite bit.  It looks great and the rifle has a snug fit, but I can open and close the two receavers easyly.  Never had any problems and the rifle shoots extremely accurate.  NOTE only take out a little bit and you wont have a problem. Just keep testing it till it fits properly.  I even touched up the hole with a super black touch up marker and you cant tell the inside was even ground.  I will try and post some pics for you as soon as possible.  It is very very easy fix and took about 5-10 min to do(I take my time on everything).

This will only lower the hole not the upper so it wont mess up your alignment at all.  Good luck.

-William

Here are the pics.  Oh yeah just to make sure some of the FAB 10's have problems when you put all 10 rounds in them.  It will accept the 10 rounds fine but will not allow the upper to close.  Make sure its actually the fit between the upper and lower and not the problem where it wont let you load all 10 rounds.  If it is the 10 round problem send it back to shoeless ventures and they will fix it for you.

Close up of the slightly enlarged hole.  It looks weird because there is a slight bevel on the bottom of the loop(came strait from BM that way) and in the pic it makes it look like a shadow or thinner then it really is.
[img]http://www.angelfire.com/ab7/sscamaro/images/ar15/ar1.jpg[/img]

Well here is a better pic with out he flash, you can really see the hole isn't that much bigger and its not even out of round(I only groud the bottom of the loop).
[img]http://www.angelfire.com/ab7/sscamaro/images/ar15/ar6.jpg[/img]

[img]http://www.angelfire.com/ab7/sscamaro/images/ar15/ar2.jpg[/img]

[img]http://www.angelfire.com/ab7/sscamaro/images/ar15/ar4.jpg[/img]

Close up of how the upper/lower fit together.
[img]http://www.angelfire.com/ab7/sscamaro/images/ar15/ar5.jpg[/img]

Complete rifle, duh
[img]http://www.angelfire.com/ab7/sscamaro/images/ar15/ar3.jpg[/img]

Good luck and hope these picture's help you, and sorry for their poor quality.  I did the fix my self because I didn't want to send it out to have them just send it back to me or do the same fix.  Worked great for me and the upper fits snug with the lower.  

-William

Lest we forget, no SBRs in Alabama?  Which means no CQBR for me![>Q]

This may work for you like it did for me.

On my PreBan Bushy, I had the same thing happen with a Colt M4 upper.  My lower fits anything but this upper.  I was getting SO irritated until my friend came over and it mounted right up for him...  I was like WTF [pissed]

I asked him what he did.  His response???

"I cocked the hammer"

Low and behold I tried it myself and it works.  The upper/lower fit is as tight as I have ever seen and if the hammer is resting against the magwell I can't push the pin in.  

This was not the problem in my case at all, I tried everything and the fix I did worked out great for me.  The only reason a un-cocked hammer would allow you to not close the upper would be that the firing pin slid backwards and when you close the upper the firing pin hits the top of the hammer.  If you dont believe me next time just push the firing pin forward.  I do however want to say that your suggestion was a very very good one hopefully this is his problem(easy fix, lol).

-William

Thank you for all the feedback,

now im contemplating whether how much of the upper i should open up on the take down pin hole...

oh well, time to get down and dirty. I'll let u know what happens...[BD]