haven't had a lot of exposure to handguns or rifles so please forgive what is probably a not so bright question - If gun shoots to the left - do I move the rear sight to the left to correct ? Just picked up an XD - 40 tactical with XS big dots and it consistently is hitting 4"-5" to left of center. I have read on the forum about factory sights being difficult to move and am wondering since it had XS big dots installed if the process would be easier. Do I just loosen the set screws with allen wrench and tap with punch/hammer ? Should I be able to do this without beating the Crap out of it ? - Comments/advice much appreciated !