Just to let you know before I am unmercifully flamed I am a rank amateur when it comes to guns so please temper your answers.
A little over a month ago I purchased an S42, 1937 Luger. It is not a collectible and because of price considerations it is what I wanted.
So far I have fired 88 rounds through it with absolutely no FTF or FTL. It is amazingly accurate.
My question is this: because of an eye problem I find that the rear sight opening is not wide enough for me to accurately center the front sight in it when aiming. Would I cause a serious problem if I were to file the rear sight a little wider? Perhaps a mm on each side?