How many rounds are fired in a burst during the sustained rate of fire of the M249?

The sustained rate of fire for the M249 is typically defined to allow for effective and manageable firing while minimizing barrel overheating. During sustained firing, the general practice is to fire bursts of 6-9 rounds. This burst size balances between maintaining a high volume of fire while still allowing for cooldown periods, ensuring that the weapon can perform effectively over longer periods without compromising accuracy or safety. The intervals between bursts further aid in preventing overheating, making this a critical aspect of machine gun employment techniques. Thus, the choice of 6-9 rounds aligns perfectly with the established guidelines for the M249 operational use in sustained fire scenarios.