Re: .243 reloading
The 70gr blitzking will do a fine job on the groundhogs it is a varmint bullet designed to explode on impact.
For deer it wouldn't be a very good choice due to lack of penetration.Unless of coarse you hunt very small deer >60 lbs or less.
If you have a reloading manual it will have many loads and bullet weights for your rifle.In a 243 a bullet in the "80-100 gr game bullet" will be good deer medicine.There are many good manuals out there ,i have 2 and will be getting more.A sierra,nosler,lee,hornady,etc.ect. manual will give you lots of knowledge that you'll enjoy for years.Best of luck with your reloading and hunting. Mike
AIPAC for president !!!!!!!!!!!!!!!!!!!