Sorry about the "bottle-neck" law rcd567, I didn't know that. diyj98 is right, the brake will make the report much louder. On the range, make sure that you've got ear protection. If you're worried about ear-damage in the field, go with a Walker's Game Ear in one ear and a plug in the other. As for the choice between the three calilbers mentioned, I'd go with the 45-70. Plenty of factory loads and even more handloads.[8D]