It isn't much of an issue if not. The primer & bullet are tight press fit & not likely to be reuined by moisture. Maybe if you soaked it in water for days or weeks, but not humidity or casual wetting.
"Given adequate penetration, a larger diameter bullet will have an edge in wounding effectiveness. It will damage a blood vessel the smaller projectile barely misses. The larger permanent cavity may lead to faster blood loss. Although such an edge clearly exists, its significance cannot be quantified".