I picked up an AR15 several years ago. Its had one problem after the other.

Ive replaced the upper(by choice, not particularly be need, but thats another story), Ive replaced the bolt catch asssembly, and now I may need to replace the mag catch assembly. The lower is a model J-15 from E.A. Co.(no longer in business) and the upper is an M4 clone from M&A parts inc.

The problem Im having is this: A full mag will not seat and catch in the well. An empty one will. Ive tried several different makes of mag, all USGI.

When I do get a mag to seat, its not at the propper level and is causing missfeeds and the bolt to hangup and not cycle properly which has also caused extraction failure.

Am I right about needing to replace the mag catch assembly? What else could be wrong? Could the bolt catch assembly be holding the mag down and not letting it seat properly? Is the mag pushing the bolt catch up too high when it does seat and causes the bolt to hang? AAARGH!!!!!!!My AKs have never given me this much grief!

Also, does anybody know where I can find someone to teach me the ins and outs of AR15 assembly and repair in WV? Preferably the Charleston, or Beckley area.

Thanks.

For starters, we are talking about USGI mags, correct?

Without having the rifle in hand, let me just take a stab in the dark.

1. The upper to lower fit is tight in regards to the amount of gap between the two.  When you load the fully loaded mag, you have to shove/bang the mag is place. Since the mag has run out of room to allow the rounds to go any further lower, you are just cam'g the shit out of the mag and button.  

2. Regarding replacing the mag button, you are wasting your time.  The problem is the upper to lower fit, including the carrier fit into the upper.  Over time, the carrier will grove/mate into the upper, which will allow you to load a full mag as the carrier will ride a little higher. But until this happens, just remember to lock the carrier/bolt back and load the mag.  By loading this way, the bullets are not compressed into the mag, and loading will be a snap.  Also, leave the carrier back when the rifle goes dry, just insert a mag, and hit the bolt release button to charge the weapon again.

Hope this helps.