Great rifle. I have owned one 7Mag Sendero and the barrel started going bad at around 1300 rounds. It still shot 1/2" on most days but was a PITA to clean the bore.
In the beginning I played with the 120/130/140gn bullets but finally settled on the 150gn Ballistic Tip, 67.0gn of RL22 and CCI BR2's. This load was super accurate (.2-.3") and the rifle killed everything I pointed it at.
I traded that rifle for a Remington 700 PSS in 7Mag. I tried to get it to shoot the 168gn Berger but had no luck (or accuracy). Finally gave up on the Bergers and tried the 150gn Ballistic Tip using various powders. When I tried IMR4350 - bam! there it is, 3 bullets 1 hole! The load (63.5gn) was actually .5gn over max as listed in Nosler#6 but it shot great and velocity was 3230fps. I was using Rem 9.5M. If you decide to use this data, work up to your rifles max.
I took a 350lb black bear in Virginia with this load at approximately 15 steps! I was on the outside row of a corn field, on my knees when he came slipping through. I hammered him through the shoulders and he never knew I was there. The bullet broke both shoulders with complete penetration.
When my IMR4350 ran low I switched to IMR4831 as I had 3.5lbs. Best load was 64.0gn with Rem 9.5M. Accuracy was .178" for three shots. I chrono'd the load three months later and it averaged 3138 fps, accuracy was .441" for 5 shots.
As for rings/mounts: I like the Leupold 1-pc Std Long Range Base and Burris Signatuire Rings (Medium), with the additional insert kit. This system effectively extends your rifles range to beyond 1000yds (in most cases).
I like Leupold scopes best, own a couple of these and own a couple of Nikon's also. The Nikons are good glass but I've read they don't have a lot of MOA in them. I have used/dialed my Buckmaster out to 1100yds, so I know it will make the trip. The Monarch that I own, I have only shot to 600yds. I will be trying it to 1100yds soon.
A NightForce would be awesome but, Man that's a lot of money! May be someday, if I decide to get a custom rifle
I might spring for one. Right now I can't see putting one on a $500-600 factory rifle. To each his own I reckon.
Factory fodder I don't invest in. Reloading is one of my two hobbies, shooting is the other! Good luck. JohnnyK.