I've only shot one cow with my 6.5 Creedmoor, and used 140gr Accubonds. The Accubonds work very well, but after some reading, I think I'm going to try to use monolithic bullets while my kids are small, just to be safe. I used the 127gr LRX @ a little under 2,900 fps last year on an Antelope and deer and was happy with the performance, so that's what I plan on using on the same animals this year, and possibly cow elk depending on what I draw.
My group uses a lot of Barnes TTSX for antelope - not because they are needed but because a) they work very well and b) in multiple cases they are the same loads used for elk and deer.
I've driven TTSX lengthwise through mule deer twice. They dropped like a box of rocks. Have sent them through mulies on broadsides with the same results. Still waiting to recover one or any tipped X bullet for that matter, MRX, TTSX or LRX. If memory serves correctly(somewhat doubtful!), I've only shot one elk with a tipped X, a 180g MRX on a 400 yard broadside. It swapped ends, took a couple steps and turned uphill. After a couple more steps it was down.
The cow I shot with a 150g AB/.30-06 was on the ground before I recovered from the recoil.
Pick a bullet you are comfortable with and go hunt elk. The truth is most bullets will work just fine most of the time. I prefer solidly constructed bullets (Barnes tipped X and various bonded for elk over standard cup-and-core for a couple of reasons:
1. Bullets that hold together penetrate deeper. If all you get is a quartering away shot or need to stop a wounded (or possibly wounded) elk that is headed to the next county, deep penetration is needed.
2. The only downside I've seen is cost, and that can be minimized by using cheaper loads that shoot to about the same POI for practice. Use the premiums for your last trip to the range. While I handload, I once calculated that they cost savings of using C&C bullets for a year of antelope, deer and elk hunting wouldn't buy me a glass of cheap wine for dinner out. Or a Starbucks coffee, for that matter. As recall, that glass of wine would have required several years worth of such savings. Hunters using factory ammo have a different calculation but often by less than anticipated. Midway has .264WM Remington Core-Lokt 140g for $53 while Nosler 130g AB is $58. That is a whopping $0.25 more per shot if using the AB. Hunters using a .30-06 have many more options and can buy a 150g Remington Core-Lokt on sale for $15 while 150g Nosler AB are $33. That is a $0.90 difference per shot, which is still not significant given the total costs for an elk hunt (licenses, lodging, fuel, food, processing, vehicle wear/tear/maintenance, processing, etc., etc.).
Daughter #1 hunted elk with her .308 Win and a 3045fps 130g TTSX for the last couple years. No shots, but I wasn't concerned about what would happen. This year she will be using a .270 Win and a 150g ABLR @ 2912fps. No worries about that, either.
