The 91/30 responds well to good trigger control and improved ammunition.
It will either make a better open sight shooter out of you or break your heart. I use the scope because it simplifies zero adjustment, and will be evaluating a Williams dovetail rear sights for the same purpose/reason. I selected the forward Scout scope mounting approach because it should not interfere with the Stripper feeding capability.
If you don't slip on a Limbsaver, you're missing a big help.
There are a number of scopes and mounts out there that look good but don't stand up to the sharp recoil of the M-N. After well over a year of buying, installing, and no-BS testing, I have concluded that any mount which mounts into the rear sight mount lacks the rigidity and resilience to keep doing the job. Simpler is better; when the retention pins holding the rear sight base in place are removed and the base is slid off, a rugged dovetail is revealed that makes an excellent anchor for an equally rugged set of 3/8" dovetail rings. I use Heavy Duty Airgun Rings and advise against the multitude of cheaper Chinese scout/pistol scopes. They either perform unreliably/unpredictably, or simply fail under recoil. I use medium height rings because they are high enough to clear the receiver/handguard without raising the scope to a ridiculous height above the bore.
Bores suffer from frosting/pitting and/or cleaning rod wear on the muzzle end. The first is inevitable and best ignored. The rifle will still respond to load development like any other and if it's done right, will perform as if the frosting/pitting simply isn't there, and besides, you can't remove it anyway. Cleaning rod wear pretty much hampers good performance. If it was serious, the bore/muzzle will have been counterbored to a larger diameter to remove that section from influencing the bullet. This is also a good thing, but the ones that 'passed' without counterboring were done to shoot to an accuracy spec that most of us would probably not envy. I actually prefer a counterbored rifle for shooting.
Handloading helps. I use PPU brass, standard large rifle primers, .311" diameter 150gr bullets, and a charge somewhere between 48 and 49 grains of IMR-4064. Your rifle will tell you how much, and it will vary by rifle since counterboring makes actual bore length a variable. This bore shortening may be a reason why M-N's may not enjoy a reputation for impeccable accuracy with commercial/surplus ammo.
The original spamcan light ball '150' grain surplus is not a bad load, and cleans up easily enough, it just takes more time. I start my bore cleaning by spraying a Windex-sorta-product down the bore from the chamber end and soaking. Patching out is followed by Bore foam, repeated until the charcoal is out. I tried Muzzleloader bore foam, and am neutral on the product. I then repeat the Windex to ensure that all primer salts are gone, and finish with a coat of gun oil inside and out.
The shim/wrap kit offered on this site should be an accuracy improvement.
Collectors will rightly eschew my approach, and I acknowledge their concerns; but these are neither rare nor complex rifles, and I am a shooter, not a collector. My approach does not make any irreversible changes to the basic rifle, and I think that's a reasonable concern when adding shooting improvements to a historical service rifle.
My development rifle has a Pro-Mag Archangel Stock installed, and preliminary testing reveals it to be an accuracy enhancement.
Greg