Dang dude, is it the magazine or in the receiver of the gun? If the cracked magazine housing is the receiver part its not a good thing...
As far as gettin sighted in, I'd start at about 25 yards and get on paper. Next would be to check at 50 if need be and then 100. The .30-06 should lay fairly flat at that range, and if your scope is close to the bore, there wont be a ton of adjustment I dont think. I'm not necessarily the person to answer this, cant say I'm qualified, but I'm willin to wing it!
Another thing is you may need a spotter with a set of binoculars.
.30-06 recoil is uhh... well its reasonably heavy for a lighter gun. How are youu benching it and shouldering it? Do you have a sandbag, backpack or bipod? If not, I'd recommend at least a backpack to rest it.
Again, take this for what its worth. I'm barely proficient with a rifle. I can hit a target, but it isnt always a pretty endeavor. Its kinda like the "miracle of birth" when you finally realize what the heck birth actually looks like. Not doin that again, I'm done. The third time the nurse was like, "You can see the head! Do you wanna touch the babys hair?" And I was like"NO! I'm fine where I am and I dont wanna remember that." Here I am today and its seared into my memeory.
Its like that.