I recently bought a Kimber Montana in 300 win mag, and I'm looking to save some time by weeding out some more of the "wrong" loads for my rifle. I am looking to hunt white tail in ND, so the size of the projectile isn't nealy as important as the accuracy that I am looking for. All shots are fired at the same range, from a lead sled.
So far I have tried: 1) 168gr Nosler Ballistic Silvertip w/ H4350 ranging from 67.0gr to 71.0gr. (In half gr. steps), and after the first trip I was able to narrow the load to 66.5gr to 66.9gr stepping up in tenths. The accuracy improved, but only pulled the group in from 2" to about 1.25". The next load, 2) 180gr Sierra Gameking Boattail w/ IMR4831 ranging from 74.0r. to 79.0gr. (in whole gr. steps), and there was no consistancy there. I am willing to do the footwork to find the most accurate round for my rifle, but I figure that while I'm not able to I could try to pick others reloaders minds. Any suggestions? Sorry for the misplacement of this post earlier.

There's a lot more to influence accuracy than tiny incremental changes in the powder charge. As a matter of fact, changes on powder charges of less tha a half grain are typically rather insignficant to accuracy.

There are enough handloading accuracy techniques and issues to be addressed that they would fill several books, so it is pointless to attempt to enumerate them in a forum post. Let's just say that bullet selection, the manner in which the brass is prepared, seating depth, concentricity, and powder selection (as opposed to incremental volume changes) are all more important to accuracy.

While I have no .30 cal. anything, I agree with Stonecreek. Each rifle is an individual and should be treated as such IMO.
When I begin loading for a chambering I have no previous experience with, I usually start with load data from a manufacurer that has a reputation for quality products. In short, I always try starting with components/data from Sierra if possible or, secondarily, Hornady.
I use their bullets in the weight I wish to use and start with their "accurate" powder and charge. I even seat to their OAL. I feel this gives me a base line to work from. Check both accuracy & velocity. I change powder weights in 1 gr. increments. When the powder & charge have been determined, I play with OAL. BTW, ideally, length should be measured to the ogive. Once I have the load combo I like, I'll then got to the bullet I wish to use for hunting and it's usually only minor changes in my load data to find a satisfactory hunting load.
It takes a bit of work but I have full confidence in all of my hunting loads and that pays off handsomely in the field.
Good luck & have fun.
Bear in Fairbanks

I suppose that I should have given more detail, but I wanted to avoid writing a book. Thank you both for your input, and I do agree with you Stonecreek, I was moreso looking for a powder/ bullet combo that may have worked in a Kimber for someone else. I started out like you suggested BiF, with Sierra bullet and the their "most accurate load," and OAL (then adjusting from there). I have been focusing on powder and bullet first, changing nothing else. There is alot to consider for an accurate load, I was just under the impression that I should fine tune after I find my powder and bullet.
I asked this question not out of lazyness or trying to cut corners, I just am not able to reload nearly as much as I would like; and also the barrel on my rifle will heat up after 2 rounds, making a day at the range an entire day at the range waiting for the barrel to cool. Any trigger time is good time, but the wife gets a bit pissed when I spend 10 hours there testing loads. Thanks again.

I have a Remington 300 WM with a Hart barrel. I'm using both 165 grain Barnes and 165 grain Hornady Interbond with 77.5 grains Reloader 22. Both bullets shoot identically with the Interbonds just a tad tighter group. Velocity is 3278 FPS.

My kimber montana will group about 1" but that took 2 years and over 300 rounds. I have a 325 WSM it will not shoot boat tall bullets . Try 180gr NP I also had to glass bed mine that help alot.

sorry boattail

Personally I would look to RL22/IMR7828 and Nosler's 180gr Ppt.
My second choice would be IMR4831 and Nosler's 165gr Accubond.

I have found over the years that a rifle that won't shoot a ballistic tip is either telling you it doesn't like boat tail bullets, or it has a physical/mechanical problem and needs professional attention. Sorry to say so, but more than one Kimber I know of has fallen into the latter group.