Shoot groundhogs with the same loads that you plan to use for big game -- if you want your varmint-shooting to be practice that will enhance your marksmanship for hunting bigger animals. Anything that you can reasonably expect to be adequate for deer is sure to be deadly on groundhogs (sorry -- I couldn't resist the opening! <img src="/ubbthreads/images/graemlins/grin.gif" alt="" />).
The hunter who knows one load thoroughly, in his gut, so to speak, is vastly deadlier than the fellow who has to master more than one trajectory, sight-in range, etc.
One charge of one powder between one primer and one bullet is also cheaper and less susceptible to confusion or error than a mixed bag of components, die settings, etc.
Get to know one load thoroughly at both your loading bench and your sight-in bench and from whatever rest or position you shoot groundhogs, and Man! are you ever ready for whatever awaits you come hunting season!
