Using a modest rifle primer in pistol ammunition is mostly not advisable. Below are a few important points to look at: ### Variations in Structure one. *Primer Composition*: Modest rifle primers generally Use a more challenging cup than smaller pistol primers, made to resist increased pressures linked to rifle cartridges. https://collinbnkwh.kylieblog.com/31903094/using-a-tiny-rifle-primer-in-pistol-ammunition-is-generally-not-recommended