Ammunition & Velocity – Hot vs. Cold Car

    Its commonly understood that ammunition that is hot will propel a bullet to a higher velocity than those at colder temperature. In fact, the 1:7 twist rate for the M16 was chosen to be able to stabilize the tracer round at sub-arctic temperatures.

    The Wound Channel did a short experiment using ammunition left in the hot sun versus those kept in an air conditioning vent. The difference of only 100 degrees is nearly 100 FPS, which with a 5.56 can be a major difference in lethality, especially at longer ranges. Its good news for our boys in the Middle-East who are plagued by high temps and something for them to look out for when up in the Afghan mountains.

    Nathan S

    One of TFB’s resident Jarheads, Nathan now works within the firearms industry. A consecutive Marine rifle and pistol expert, he enjoys local 3-gun, NFA, gunsmithing, MSR’s, & high-speed gear. Nathan has traveled to over 30 countries working with US DoD & foreign MoDs.

    The above post is my opinion and does not reflect the views of any company or organization.