RAW it states you use BS to use a pistol in CC. I was feeling it would more appropriate to use WS. While locked into melee, it makes more sense that combat style would change. Or possibly a penalty if you engage with someone with melee weapons and you have none.
Besides from parrying, It would make more sense damage wise to build a high BS character with some awesome talents and use 2 bolt pistols fire semi auto.
do you think it would make melee weapons more attractive than the 2 pistol route?