Thats easy, not only do i own an X-150 i too am from colorado.
First thing you'll want to do is look at the barrel and the stock, take note of all material touching the sides of the barrel and once its all marked, use a file and take off all the marked spots until there is no material touching the barrel.
To help you with powder and Bullets, Pick up a can of pyrodex RS loose powder and either some 350 grain TC maxi hunters Or 385 grain great plains bullets. By taking off all the material touching my barrel i was able to go from 2 1/2" groups @ 100 yards, down to 1" groups at 100 with open sights. That was with shooting 90 grains pyrodex rs and 385 grain great plains bullet.
i also use the TC speed loaders, they have a built in 209 primer holder and i load up 5 or 6 of them and keep them in my pocket for hunting.
Primers- Use either CCI or Federal primers or winchester w209. I like the cci's best due to them not covering the bolt with a lot of fouling.
Breech plug- My favorite plug grease is Gorilla grease, Only finger tighten your breechplug after cleaning.
If you have a hard time seeing your sights in dim light, like i did, Go to cabelas and order Truglo sights for $43 + shipping, You wont regret it.
If you ever want to shoot sabots, use a .45 sabot, ive gotten the best accuracy from them and only use them for plinking targets at 200 yards.
But make sure you remove all the material touching the barrel, you can also remove the barrel after shooting and if you see any shiny rub marks on the barrel, thats messing up your groups and needs to be removed!
Another easier way to find where its rubbing is to slide a sheet of paper between the barrel and stock, where ever it stops, mark the area with scotch tape, take off the barrel and take that area down. refit the barrel and do it again untill the paper slides down to the first lug.
Good luck and enjoy it! I've had mine for 4 years and never had any problems with it, good quality rifle.
