I'm having a similar issue of rounds not chambering in my 300 WSM, but to a larger magnitude. I have to full length resize rounds with 0.010 shoulder bump to get them to chamber with a couple thou clearance. This means I'm having to excessively resize my brass. For example, can take a once-fired case at 1.773 that just barely chambers, then FL resize to 1.770 and it will not chamber at all- hard bolt stop. The resizing in my FL Hornady Custom die causes a bulge in the shoulder that effectively makes the cartridge "longer" as far as chamber fit goes, so I have to resize to 1.766 to accommodate the shoulder bump plus a little clearance.
Here's some measurements on 2x fired brass to clarify the issue:
1.775 longest fired length, doesn't chamber.
1.773 average fired length chambers (tight)
1.771 shortest fired length chambers with 1 layer scotch tape (I should be shooting for this length).
1.768 longest FL resized round case that chambers (tight bolt)
1.766 longest FL resized round that chambers with 1 layer scotch tape (~1.7675")
I've sharpied the shoulders of fired and re-sized rounds, then spun them in a Wilson Case gauge and the buldged shoulder is evident on the resized round, whereas the fired round just shows a thin mark at the base of the neck/shoulder junction. I'm using Hornady custom dies and #35 shell holder.
I'm at a loss as to how to change my die setting to achieve 0.002-0.003 shoulder bump from 1.773 to have a cartridge that chambers with a few thou clearance to spare. Does anyone have any insight on whether I can bump only 0.002" with my FL die without affecting shoulder shape?