So, I stumbled into a Husqvarna Mauser-Action sporter that has my interest.  The receiver has been drilled and tapped by someone (not at the factory; one threaded hole is through the Husqvarna logo).  Anyway, how can I make sure that the drill/tap job was done properly?  I can't find any cracks in the receiver, but how do I know the holes are aligned properly?

Thanks in advance.

Set it up on a mill dead level, center in on one of the holes and travel the table checking your center on each hole.

Is there any way I can check it without using a mill?  I'm trying to decide whether or not to purchase it.

A fast way is just take a ruler and put one edge over all of the drilled holes so the ruler is aligned with them equaly. use the ruler to the right side of the holes. now eyeball the outside edge of the ruler so it is over the reciever rail that the extractor normaly lays over. The rulers edge should parallel the reciever rail perfectly where the wood runs along that rail edge. Now if the reciever was drilled on a forester jig with a straight barrel, it should line up fairly well. Sometimes you can get a little off with the holes if the barrel had a slight bend in it since the jig uses the barrel as its guide for the hole locations.