A friend of mine and I built an A1 from a DPMS lower and parts, and a govt upper ,from the early to mid 70's.  All went well until we took it to the range to sight it in.  It is IMPOSSIBLE to push in the detent pin (?) to move the rear sight.  We tried using a sight tool, bullet point and a drive pin, nothing works.  What is the next step?

    Also, the bolt release will not keep the bolt in the locked open position.  It looks like it is installed properly, but it won't hold.

    I also have another A1 that a friend gave me the lower receiver for it.  I think that it is an early Olympia also from the mid 70's.  The area that holds the roll pin for the bolt catch was drilled crooked.  The aft "ear" has no metal in which to put the roll pin.  Can that area be built up with aluminum and redrilled so that it is straight?  Is this a big problem to do?

Thanks in advance,
Colt1MB

Stickman:
    Thanks for the reply and the suggestion.  The upper is "new" mid-70's military.  The only marking that I can find is in the bottom part of the handle.  It has a P and an M, but not together.  I have NO idea what that signifies.

    The magazines were mainly "new" unused 20 or 30 round military, still wrapped up with preservative on them.  I scrubbed them well, and they appear to work well in all other respects.  I'll borrow a couple of mags to see if there is any difference.

    We will take the rear site apart, and clean it well and see if that works.
Thanks,
Colt 1MB