Luie: With Each new MLer, in different calibers, or different barrel lengths, YOU NEED TO GO BACK and do comparison PENETRATION TESTING to see just how effective a smaller or large caliber RB will be on game. You have some practical experience using a .50 caliber gun to take deer. NOW, use one of those loads, to compare to your best load in that new .45.
This is the ONLY way I know that you can learn about the capabilities- and limitations- of any given caliber and rifle.
I think you will be pleasantly surprised at just how well a .45 does in penetration tests, at various distances. I would not hesitate to take a Heart/lung shot at any sized deer out to 80-100 yds. My limitations would have to do with how clear a shot I might have, and the weather conditions, or time of day. MY ranges shorten considerably in overcast, or darkened conditions.
Back in 1968=69, I was a deer checker for Monroe County, Illinois, down below St. Louis, and saw several large bucks brought in that were shot with .45 cal. Muzzleloaders using PRBs. Ranges varied from 3 yds. out to 60 yds., but most were taken at well under 50 yds. I don't recall the weights of those bucks, nor how many points they had, but live weights were well over 200 lbs. Dressed weights were in the 180-200 lbs areas.
One had a dressed weight over 200 lbs. and drew the attention of every hunter around the check station, and from the two bars nearby. At that time, using any MLer was a rarity, and I listened to lots of those hunters express amazement that such a big deer could be taken with such a small "Caliber" rifle. I didn't know much of anything about MLing rifles at the time- and owned NO mlers. So, I just listened to both the questions, and the answers as I went about my work of collecting data for the Dept. of Conservation( Now, Dept. of Natural Resources.)It was years later when I got my first Mler, a .45, that I joined a couple of other club members at the range to do comparative penetration testing with my gun and theirs. Later, when I bought my .50, I set up my own penetration box, and tested that gun, comparing it to others.
My .45 had no problem penetrating 6 1" pine boards spaced 1" apart. That is 12 inches of air and wood! The biggest bucks I checked in did measure more than 9 inches across the ribs, behind the forelegs of the deer. A broadside shot would have easily penetrated both sides of the deer, leaving both and entrance and an exit hole. The exit hole would be over .60 caliber in diameter. My .50 RB penetrated 8 1" pine boards and 8 spaces = 16" and the flattened ball was close to .90 caliber.
So, do you own penetration tests to give yourself an education, and the confidence you need to use the new gun to take game. You will gain a lifetime worth of education doing so. :thumbsup: