308 It sounds to me that you applied pressure to the barrel via the stock when you wedged it into the bags. That will torque the barrel and change poi on every shot.
If possible pick up a bench rest even a inexpensive Hoppes is better than nothing, the bags have a tendency to change forarm position even the slightest change makes a big difference at 100 yards.
I have a model 10 fp 308 and it shoots 150gr. smk's to about .4-.5 consistently, a model 10 fp in 223 that if I do my part stays in the .3-.4. I also have 3 more Savages that are sporter barells that stay well under an inch@ 100 and 2 in the safe waiting to be sighted, hopefully they will do as well, but all my shooting for groups is done off a rest with a bag in back.
All my rifles are Savage except for a Bushmaster and I would not consider anything but Savage for a bolt action rifle.
Don't give up I'm sure it is something simple that can be corrected easily, like someone else said find the load it likes first then work on the other things.