Probably the main reason I don't have a Cooper in the 260 Rem is that other than being a Cooper nut I'm also a Sako nut. I've had the 260 Rem in a Kimber Montana and now a Sako Varmint laminate w/ set trigger. Its a shooter for sure.
I started collecting small caliber Coopers about 10 years ago. At that time they were not making repeaters other than rimfires. I've been thinking lately of a model 54 Excalibur in either 260 Rem, 22" barrel, and having the whole thing Cerrakoted. Or, an Excalibur in 6.5 x 284 done simalarly, but with a 26" barrel. My problem is that of the dozen Coopers that I have owned, all have been bought used at very reasonable prices. I've only been able to score one repeater cheap.
Here's how the Sako shoots.
Started with IMR 4320
but have settled for H-414 as my go to load with 130 gr. Accubonds. I could develop a load that would get more velocity, but as most of the shooting I do is 200 yds. and under and I like to eat right up to the bullet hole, starting MV's of say 2,800 fps or less don't seem to do as much meat damage.
But hunting season ain't here yet and ya never can tell.
Hope you continue to enjoy your rifle.
Best
GWB