nodeeriniowa -
Funny - when I was growing up in Iowa in the 50's and 60's I only recall seeing a couple of deer and one of them was at night, crossing the road in front of us as we drove to the drive-in theater in Iowa Falls. No when I go back to the same family farms I often see more deer in a day than I can count.
Congrats on your choice of the Ruger 7mm RM. My first centerfire was also a Ruger (M77) in 7mm RM and it was the only bolt rifle I used for elk for the first 20+ years of elk hunting. That 7mm RM has taken more elk than probably all my other rifles combined. Also got my last elk. a 6x5 bull, at 411 yards using my buddy's Ruger MKII 7mm RM and the same 160g Speer Grand Slam handload I had used for the first 20 years.
Since you don't handload your options will be limited by factory offerings and/or what you can afford. While the truth is that most bullets will work most of the time, I prefer a bullet that provides reliable, rapid, controlled and limited expansion. For this reason I handload various 'premium' bullets for hunting and standard cup-and-core bullets for the bulk of my practice. (I match trajectories as closely as possible and re-zero for the last couple of practice sessions before the hunt.)
There are quite a few bullets I recommend without qualm:
Barnes TTSX and LRX
Nosler AccuBond, AccuBond Long Range and Partition
Federal Trophy Bonded Tip and Edge TLR
Swift A-Frame
Although my hunt group uses a lot of Barnes TTSX and LRX, we have yet to recover one. I've driven two TTSX lengthwise through mule deer. While some people claim the TTSX/LRX doesn't drop game as quickly as other bullets, we've had a little over 50% instant, straight-down DRT results. I have seen a number of elk taken with a Partition but have never used them myself. (I still have a Federal box with 17 Partition rounds in it left over from 1982 when I checked them out at the range.) AccuBonds have worked on elk in every weight and caliber we've tried. My hunting buddy has used Trophy Bonded bullets successfully in his 7mm RM and I think the new Trophy Bonded Tip and Edge TLR are even better due to their hight ballistic coefficient. (They shoot flatter.)
You might want to consider a couple changes to your rifle. The first is to replace the laminate stock (even though it looks great) with a synthetic to reduce weight. The same goes with the scope. A smaller 3-9x is all you need. Get a stretchy sling, too. You can thank me after dragging the rifle over a couple of mountains.
Another item about the scope - get one with a drop-compensating reticle and learn how to use it. Also, get a laser rangefinder good to 800 or 1000 yards, even if you plan to limit your shots to 500 yards. IT is often hard to get a laser reading at 500 yards with a rangefinder rated for that. The extra range helps ensure you get a reading at a lesser range. FWIW, My Leupold rangefinder was rated at 1000 and was crap. My Nikons have always read at their designated range in good conditions, and my 1000 yard Nikon hit an elk at 1104 yards last fall. Before you buy a rangefinder, take it outdoors and give it a try.
I said a smaller 3-9x scope is all you need. Elk are big animals with large kill zones but I've hit clay pigeons on the 600-yard berm using various rifles and 3-9x scopes with drop compensating reticles.
Good luck on your hunt and have preparing for it.