Due to the relatively low-powered round it fires, the M39 is ineffective against armored opponents. It's lack of penetrating power also makes it useful in urban operations where collateral damage may be a concern, as walls and other obstacles in the environment will effectively stop stray rounds, thereby minimizing the risk to innocent bystanders. Even though the weapon fires a relatively small round, the M39 has extreme recoil, even higher than that of the M41A Pulse Rifle, especially when the weapon is equipped with the Magazine Accelerator.