You can easily see if your barrel is bent just by looking down the bore. Just look through it and get the hole in the end centered in the middle of the chamber. If it is, it will be easy to see as a change in the 'swirl' of the rifling.
I bore sight all of my scopes this way when mounting them, it usually gets me on the paper, about 8" low at 40 yds (my back yard target distance) and I can adjust from there. Usually about an inch low at 40 will put it very close at 100 and I can fine tune it at the range. 44 Man