I don't use the fancy led sled rests. I use bags and try to simulate a real hunting situation.

I own a LOT of Brownings, they all shoot well. In 7-08 I use 140 gr, but honestly I haven’t found an ammo it won’t shoot well. 139 gr Hornady whitetail, 140 gr Winchester grey box, 140 gr Winchester ballistic tips all group the same in my 7-08’s.
Sorry you’re having problems. I’m gonna say it’s not the gun BUT I guess it could be. I shoot off of sand bags mostly too and I can get 1-1.5 groups all day.
I also would have a hard time believing it’s the Leupold, but it’s gotta be something right.

It may just need to be shot more to get better. I know it's not me because I shoot MOA with all my other rifles.
I did have a better day today with the old school cheap Federal blue box 150g. Took 9 shots and was consistently getting under 1 MOA.
Sometimes those expensive fancy bullets just ain't worth the money.
My last group was 0.66 MOA.

Glad you got it to shoot straight and found ammo the barrel likes!

Ol cheap blue box has shot great in everything I’ve tried it in and I’ve killed a pile of deer with them.

Nice! I’m glad you got it figured out.

Ben, I have a 7-08 Kimber Classic that was a big disappointment at first, so much so, I had Simmons in Bessemer send it back to Kimber. They throated the chamber an additional amount and recut the crown and presto, it is now a great shooter. The target they sent back with the rifle was shot with 150 gr Winchester Power Points. They said that was the first one they tried when a gun came back because of it's accuracy potential. I would have shot every thing in sight before I tried those, so 'ya never know what a rifle will like. Congrats on getting yours shooting like the pic shows.