If you can't afford to buy another gun, I would suggest experimenting with different loads. Or, if you're like me, you can find some cheap bullets, such as XTP's, and experiment with different target mediums. For example, this summer I intend to find out how a 250 gr. XTP would perform on prairie dogs and jackrabbits at varying distances. I think the results might be interesting, definately worth testing anyway.
Vince