OK...... This has me stumped.

So I'm turning to the smartest group of re-loaders I know. I am shooting a Stevens 200, 25-06. Load: R-P cases, WLR primers, Nosler BT 100 gr, H-4895 powder, bottom book load 40.0 gr, Seating depth .020 off hard land contact. This rifle has a short throat. (Sierra 90 gr HPBT loaded to book length are showing land contact.)

I am showing flattened primers with the bottom book loading listed above.

My thought was short throat, coupled with a possible tight chamber. I need some help understanding whats going on, and what to do about it. Any ideas?