I'm looking for an outside holster with thumb break or similar retaining mechanism for a G19. I'm not thinking about concealed carry and fast draws here, more for carrying the gun on hiking trips, etc.

Something in nylon/heavy canvas would be preferable but leather will do as well.

Thanks in advance!

I like my blackhawk serpa I carry a model 23 in a lot. Uncke mikes has lots of low cost nylon holsters that well fit the bill.

I use one of their shoulder holster for bsck packing all he time.

100% on the Serpa. It is a very secure holster which will prevent you from losing the gun on a rough climb

I use a Desantis leather holster with the 2 angle options. I do use it for concealed carry as well as all around and love it. It's got a thumb break and an open muzzle.

Google up the SERPA issues. They are linked to a high incidence of NDs, and can be locked shut by grains of sand. If you want an OWB retention holster get a Safariland holster.

Take a look at 'Simply Rugged' holsters. Very good quality and good service. They hold up real good.