I posted last year about my experience with this caliber in the K31, and Happy Jack commented that he used Imperial Lube. I abandoned castor oil because it is labor intensive, switched to Dillon lube with great results - every case is sized to chamber every time. Were Wilson to make a case gauge for this caliber, that would make QC easier because it wouldn't be necessary to chamber -check every round.
Here's the earlier link:http://www.sassnet.com/wildbunch/forum/index.php?topic=2090.0
When the cartridge doesn't full chamber, the operating rod protrudes slightly in it's channel in the bolt, and a loud click is heard when the trigger is pulled but the firing pin hasn't impacted the primer, maybe at the most a faint dent is put into the primer. Slamming the bolt fully forward and recocking the firing might work, but that may also jam the oversized cartridge into the chamber with a long recovery time. Better to eject that misfit and have extra ammo on hand.
If this failure to fully chamber happens, it's time to back up to the sizing die. Check the cases in the K31 after sizing and trimming to TTL and before further processing them. If they don't easily chamber, either the case is not fully sized to the base or the shoulder set-back is off.
The Redding sizing die for K31 reloads eliminated almost all problems and the Dillon lube provided the remaining solution. Chamber checking for QC is necessary.
Other K31 shooters please jump on this and share your experience. Many others are buying and shooting these K31s.