I would hook up with a more experienced shooter at the range. It is likely that you aren't holding your rifle correctly.

A lot of the advice here is to go with a lower cartridge but I don't think that is completely necessary though I would agree that you don't need a mag to hunt deer.

I went through this with turkey loads out of a 12 guage. With the proper technique I can now shoot off over 20 turkey loads with no trouble at all.

Tom