That ended at the beginning of Captain America: Civil War when he detonated the explosives on his belt in an attempt to kill Steve Rogers, but Scarlet Witch prevented that by transporting into the air.
Unfortunately, the blast that incinerated Crossbones also killed dozens of civilians in a nearby building, which led to the passing of the Sokovia Accords.
Upon recovering, Brock Rumlow took on the Crossbones identity, left HYDRA and began his own campaign of terror.