If your holding a 1/2 minute at 300 you have a good rifle and I'd not change a thing. Now, what I mean by 1/2 minute is a little different than what most assume.
If I take a gun and go shoot a three shot group at 300 yards and I have a 1.5 inch group on the target I really don't have a half minute of angle rifle. (yet) I just have a gun that shot a 1.5" group at 300.
Even the fat kid has a good day on the basketball court now and then. . .
Now on the other hand if I go to the range with a box of 50 rounds and I shoot a series of 5 shot groups until that ammunition is all gone and they ALL stay within that same 1.5" circle at 300 yards then it's a certainty that chicks are going to ask me for my number and I'm going to get laid more often. (has
to be that way. . .)
That's the difference. If you want to take it one step further you do this a few different times. Once on a hot day, a cold day, and a rainy day and you then compare things. If the bedding is working, you will see almost no shift in group center. (ideally none, but temps and humidity do fiddle with powders a bit so we'll blame them) If stuff starts meandering all over the target, then I'd look at having some work done to the stock.
This is certainly more work and most don't want to devote the effort, but if you want it done right, that's how you do it. Just think of it as the more effort you put into learning how your equipment works, the better shooter your going to be.
Good luck and all the best,