For years I have owned Remington 788s' in 7mm-8 and .308 without any problems whatsoever; great accuracy!  Recently I acquired one in .243 which is a great shooter also and after a few hundred rounds no problems occured.  However, the prior owner "dremeled" off about a quarter of each lug (3) on the top and right side of the bolt when it is in a locked position because as he says, he experienced headspacing problems many years ago and he has not had any after that modification.  There are still 3 good lugs on the left side.  Somewhere I read about headspacing problems with the 788 in certain calibers but never had any myself in the 7mm-8  or .308; I shoot factory ammo only.  As I said, I have not experienced any problems while shooting this one in .243, it is a real tack driver!  But is it safe?  New Bolts are soooooo expensive!