I have taken or seen taken at least a dozen elk with BPC cartridges from 45-90 to 40-65 and can say in my opinion that they all worked very well with pp bullets and grease groove bullets. The 40-65 is easier on the shooter and also easy to load for and is my current favorite but i could not tell a lot of difference on the critters with any of them. Get one and learn to load and shoot it and go hunting! good luck!