That scope should work out fine,you have enough magnification to shoot long and short.

If you wanna get a new scope,any standared 3-9 varidble should work.I have 3-9's on almost all my guns and many never leave 4x or 6x.I have shot deer and antelope out to 400+ yds with just 4x,so you should be safe.My 30-06 carries a straight 4x and I have never had a problem.
BBJ