If I'm sighting in a new gun with a newly mounted scope I have the gun Bore-sighted then I take the Rifle to the Range and start out at the 50 yard sight using my Caldwell Leadsled.I set up a target on a larger white back-board because sometimes it can still be off paper?I get it sighted in as best as possible out to 50 yards then after I'm happy with the results I move out to the 100 yard mark and finish sighting my Rifle there with 3 shots,then I let the barrel cool down or shoot one of my other Rifles I've had for a while that I want to check to see if they are still on-target...after several minutes of messing around adjusting the scope etc...I shoot my first Rifle again with 3 shots and adjust the scope accordingly and repeat if neccessary.I simply love my Caldwell Leadsled and it has helped me get my Rifles sighted in with tighter groups...then after I get the Rifle sighted in I shoot a few rounds free-handed on a rest or sand bag by myself not using the Lead Sled any more!