you can sight in very quickly with this method:
set up a target at 25 yds (use a large piece of cardboard or paper.. at least 24" x 24")... and draw a 1" dot in the center..
set your rifle up on some sturdy sandbags or better yet some kind of rifle vise..
aim the cross hairs on the dot and fire one shot..
after the recoil settles, put he cross hairs back on the dot..
being very careful not to move the rifle.. look thru the scope, and have someone adjust the windage and elevation until the cross hairs are on top of the hole you just shot.. (if you have a vise type of stand, you can do it by yourself)
your rifle is now sighted in for 25yds.. this will put you on paper at 100 yds and all you have to do is fire a 3 shot group for fine tuning..
this method works best with some kind of vise, but i have done it myself plenty of times on semi-auto rifles that cant be bore sighted..
this will save you some ammo and leave you with extra for plinkin'