fossilesque@mander.xyzM to Science Memes@mander.xyzEnglish · 1 年前Burning Upmander.xyzimagemessage-square523fedilinkarrow-up11.31Karrow-down1110
arrow-up11.2Karrow-down1imageBurning Upmander.xyzfossilesque@mander.xyzM to Science Memes@mander.xyzEnglish · 1 年前message-square523fedilink
minus-squarealcoholicorn@lemmy.mllinkfedilinkEnglisharrow-up7arrow-down1·1 年前In the same way a US ton and a metric ton is like 10% different, a 556 bullet is actually 5.7 mm across.
minus-square Morphit @feddit.uklinkfedilinkEnglisharrow-up11·1 年前Because the minor diameter of the barrel is 5.56 mm and the major diameter is 5.69 mm. If the bullet were smaller than that then the propellant would blow past it. They didn’t make a 'murican millimetre like they did with the imperial system.
In the same way a US ton and a metric ton is like 10% different, a 556 bullet is actually 5.7 mm across.
Because the minor diameter of the barrel is 5.56 mm and the major diameter is 5.69 mm. If the bullet were smaller than that then the propellant would blow past it. They didn’t make a 'murican millimetre like they did with the imperial system.