Long barrel uses

[Puretexan]

I see lots of posts about lugers, but really none about the
use of different barrel lengths. Why would someone
have a 12 barrel issued to him? It looked like you could
beat him to death with your shoe , before he got it out
of the holster. Then the long barreled one with the big
sights. Did they shoot off of navy boats and needed the
range? Seems like they would have standardized the
barrel length to around 4'' and been good.