Man I have been down this road!! I traveled it extensively for the last year.
When I first got my senderoII last year I broke in the barrel with factory ammo. I didn't reload at the time. I vividly remember my last three shots in the breakin process forming a nice .6 group.
I shot the gun all throught hunting season. By that time I had started reloading. There is only so manytimes a man will pay $40 for a box of ammo before he decides that there must be a better way to skin that cat. I noticed that sometimes I would go to the range and shoot great groups in the .3s and .4s. Sometimes it wouldn't shoot but MOA or so. Some of it could have been my reloading process but who knows.
Well in Feb I had a 26" Shilen barrel installed. Action was blueprinted. The gun shot some better. Still the occasional bad day where the groups would really open up. Inch to 1.2 inches. Got a new stock. Got a better trigger. Finally got it bedded with devcon steel.
Don' ask what took so long to get it bedded.
Now with 180 bergers with a MV of 2950 I can readily shoot 1/2 MOA groups out to 300 (farthers my range goes). More times than not I'm down around 1/3MOA.
It has been an expensive time consuming process. I've put 750-800 rounds throught this gun in the last year. 659 since I got the new barrel in late Feb. I've shot mostly bergers but some AB's, Amax, and a few Barnes.
If I had it over to do again I would
1)Definately stick with the 7mm RM. It has manageable recoil and a great bullet selection. 100 Vmax up to 180 Berger's. I keep the MV down around 3000 because that is where some of my best accuracy seems to live.
2)The out of the box rifle is pretty good but with any factory issue anyting there are some potential lemons. Some potential marginal guns and some dead ringers. First thing I would do is to replace the trigger with a basix or jewell and bed that bad boy like no body's business. I think that the HS precision stock is great but with lots of shooting it rubs on the action. I think that alone accounted for the finicky nature of the gun.
3)If you know a good smith the I would strongly consider building one from the ground up. I had lots, and when I mean lots a I mean a whole ton, of free help. Eddybo put lots of time and effort into this gun. Lots of free help. New barrel, chamber and Blueprinting, new stock, new trigger, bedding, and soon to be new firing pin. Were talking beyond &1500 I'd imagine. That plus the 1k sticker price have you well up there near custom levels.
Now you might not be as obsessive about you gun as I was/ are and I haven't shot and AB's in a while so I can't speak to the accuracy. I got several good groups before the barrel change. I'm going to try unbonded, more frangible bullets this season. Whitetail just aren't that tough.
I hope this rambling story has helped. My wife is watching "The Notebook" and I don't have anyting else to do.
