I've improved accuracy on injection-molded stocks by pillar-bedding and adequately free-floating them.
On some, I've also added epoxy-filling in the forends because some don't have X supports, only diaphragms, which don't provide adequate lateral stiffness. I foamed the cavities and filled the top 1/8" with epoxy.
Even one Model 7 stock that was split was repaired with a piece of bolt epoxied across the split and pillar-bedded. That rifle shot 1/2 moa with 140 gr. Core-Locts!!!