Try using the M1 carbine. It will make people bleed with one shot. In nearly all cases, they will drop to the ground, not shoot back, and be unable to sprint, as is intended. This makes the follow up shot to finish your opponent off much easier. It actually affects gameplay a lot when using the carbine. However, with full caliber weapons it doesn't affect gameplay much, as your opponent will only bleed with the very rare limb shot.
Keep in mind, rarely will people die from bleeding out, but rather they'll be disoriented, which is the purpose of our bleed system.