Help with Nosler 6.5 CM brass

[55stone]

I have a new Tikka stainless 6.5 CM (love it so far, shoots great) Has 41 rounds through it. I bought 2 boxes of nosler BT to help break the barrel in and to just shoot while I worked up some handloads.. from the beginning with the nosler factory loads it was hard to close the bolt on.. some of it pretty hard.. I shot a handful of them and stopped. I just assumed the shoulders needed bumped or bullet was into the lands hard and was going to wait to see how some of the new starline brass handloads went. so i loaded some up with 147 gr hornady ELDM's with H4350 in starline brass I had no issues chambering any of them.. I measured the once fired shoulders of both cases ( with hornady comparator) and the nosler was smaller than where I was going to even bump the starline back to by .003..so .006 smaller than the once fired starline which is weird it didn't expand to match...next I noticed length of the nosler was .010 longer than the star line but the nosler were at trim to spec of 1.910..the starline are shorter at 1.900 so just to see I trimmed 2 noslers back to 1.900 to match and they still won't let me close the bolt on them easy..Any other thoughts of what it could be? Not a huge deal if I can't use the nosler brass but I just don't like not understanding things lol.. the rifle has been great.. it's been sub MOA with everything I have thrown at it, trigger has no creep is a little heavy. Action is smooth, extraction has been great!.. pretty impressed.. thanks for any help guys

 

[wv270wsm]

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