Thread: suggestions on material to build up rifle stock grip

i want to change the shape of my boyds stock to have a more pronounced vertical pistol grip and slightly larger palm swell on the left side.

at the moment I have a temporary fix using some closed cell foam sleeping mat and electrical tape the Mrs just rolled her eyes when I showed her the latest mods, haha.

what are good options for this type of job ? standard old builders bog or car body filler ? perfect option would be something that stays in a semi pliable state where I can mold it wearing a latex glove etc... reasonable grippy rubber finish would be a plus too.