Browning Beef Stew (safety question)
Yes, a simmer will be on the order of 180 to 200 F (82 - 93 C) which is a safe temperature for cooking and holding stew.

Browning beef does cook it, but usually not all the way through as that is not the point; instead it is to develop the flavors.  The full cooking is done during the braising or stewing stage while you simmer it.  This also allows the collagen to hydrate into gelatin, creating the tender texture of well cooked stew meat.