Simply put, If you line your 7mm mag up at 250yds, the bullet will rise above the line of sight 2.5in at 175yds, and drop 2.5 in at 350yds. Your point blank is 5in and your max point blank range would be 350yds. Juat an example.

Mounting your scope at 1.5in and lined up at 150 will make your bullet rise above the line of sight 3/4 in at 100. If you had high monts and your scope was 2in above the bore, it would make the 100yd rise about an in maybe. It dont throw it off much, but it can a little. another example

Pretty much, the higher the scope, the higher the bullet has to come up to meet the scope, and that makes it creep over the line of sight more also. making your pont blank different. Thats the best I can do.