Problems sighting in Rem. 760

[Marlin444]

This am tried sighting in my 760 (1968) 30-06 I just piced up.I put a new Nikon buckmastes scope on it, all mounting screws are tight.I 'm shooting my handload with rem 150 gr. psp  & reloader 15 (53.0).I'm shooting @ 100 yrds. off a sand bag.It put 2 within 1" of each other, now its putting them low and 4" -5" away.I was supporting the forarm with my hand.Any ideas? Opening day is a week away . Thanks!

[bcraig]

Possibles list
Scope gone bad(even new ones do)If you have a PROVEN scope try it.
Barrel is loose(put a steel pin in holes of tube that holds barrel on and see if you can tighten)
Scope rings too tight(only need to be as tight as a couple of fingers and thumb can get it when placed on end of screwdriver)
Accidentally put different Powder charge or bullet in case or Mixed case brands used different primers etc(try a box of factory loads)
Were you using a sling when shooting one time but not another ?
Holding forearm in different place Shooting time the same between the shots ?
How was your clothing on the different day ? Heavy thick coat one day tee shirt the next ?
Wind and shooting conditions the same ?
Have you accidentaly damaged the crown on the end of the barrel since shooting the rifle so well ?
Sand bag rest the same from one day to the next ?
Barrel fouled excessivly ? Clean barrel
Did you run oily patch in barrel after shooting good groups? if so wipe dry and shoot 3-5 fouling shots.
So many thing it could be but these are just a few that you might think on.

Craig

[oneoldsap]

   Maybe your scope is just getting settled in . Are your bullets grouping ? If they are grouping , readjust scope and shoot some more . It's kind of hard to drive tacks with a strange gun , get a little better aquainted with it . Did you make sure the barrel isn't copper fouled ? Seldom is the first load tried the keeper .