I've looked around for answers on this but the most recent stuff that comes up is from 2017.  I'm shooting a 92fs in Production.  There is zero bevel on the magwell, the sides are 90 degree angles.  I'd like to knock that sharp edge down a bit and bevel it a little.  As I read the rules, obviously any external magwell or grips that form a magwell are prohibited. But, it seems that beveling the internal edges would be allowed. It's an internal modification as it's invisible with the mag inserted. Appendix D4 22.4 states "Internal magwell dimensions may be increased. Aftermarket external flaring is prohibited. Markings inside the magwell are allowed".  This seems to specifically allow the modification as is required to be legal.  The only limitation seems to be found in the USPSA Production Gun List, which states that the internal lateral width of the well may not be more than 1/4" wider than the magazine body; therefore, an 1/8" or less bevel on either side would be allowed.

As the rules read now it seems pretty obvious that it's okay, but in the older threads I found the consensus seemed to be that it was prohibited. Of course, those also made reference to markings inside the magwell being prohibited, so it seems that this may be a rule that has changed.

I dunno, from a newbie perspective it seems the stuff they're allowing are mostly the type of mods people might make to their carry guns anyway.  Better sights, extended mag release, etc.  Until they increase the mag capacity limit and allow magwell funnels, it's going to be pretty distinct from Limited.