I like Hornady dies. The seater die has a little sleeve that helps to decrease runout of seated projectiles.... theoretically. Not having a runout gage I have no proof but it sounds good to me. Heck, hand loading is just like a huge science fair project, so trying different stuff is how we learn new information.
Given the choice between chamfering (an insignificant "thinning" when done correctly) and crushed/buckled shoulders, I would pick chamfering.
Its what I had to do when loading .22 Hornet, even fired brass would sometimes collapse when seating the bullet, until I gave the case mouths a "generous" chamfer. (the brass is really thin)
Other cartridges I chamfer (lightly) new brass and trimmed brass. Never needed to chamfer fired cases, unless they had been trimmed, which creates a new square shoulder edge to the case mouth.
I, also was one who read 6.5cm as 6.5 centimeter (65mm). "cm" is the standard abbreviation for centimeter. "CM" or maybe "Cm" might be acceptable as an abbreviation for "Creedmore" but "cm" is automatically read as "centimeter" by most of us. Spelling out the full word, once (at least), before going to an uncommon abbreviation is a good idea.
Creedmore. Spelled out once. Picked up a set of Hornady dies at Acadamy after range trip. Used the headspace compareter and set shoulders back .001. The sizer works great. Seating die has some really rough threads at higher end and lower end of turn in the die. Midway it's smooth. I loaded up a few accubonds for the heck of it and they will work. Depending on how loads come out I may go with Redding full length die set and a Lee neck sizing die.
Wendy its Creedmoor...lol but enjoy your new rifle the 6.5CM is a great cartridge my wife absolutely LOVES hers. We use 129 grain Interbonds and H4350.
My iPad doesn't recognize it and if I don't watch it spells what it thinks is correct. Lol. I'm hoping to speed up my reloads more than the factory. Box showed around 2710 fps with 140 grain bullet but my chronograph was 50 fps or so slower. I've been loading up some 130 grain Nosler Accubonds this evening and going to load some 143 Hornady Eldx tomorrow. I really enjoyed the rifle at the range today with exception of heavy rain. I usually just print my own paper targets and the ink was running on them. I'm using H4350 myself right now but have some other powders to experiment with. H4350 was my perfect powder for the 260 I had.
Reloader 15 and 130 grain bullets are an awesome combination. I get sub 3/4 inch groups with it. Most are closer to 1/2 inch with heavy wind, and a target that has 2 inches of play in the wind.