高级玩家

- 贡献度
- 7
- 金元
- 2620
- 积分
- 290
- 精华
- 0
- 注册时间
- 2011-4-5
|
Americans would define the shoulder angle at alpha/2 = 23 degrees. The common rifling twist rate for this cartridge is 305 mm (1 in 12 in), 6 grooves, Ø lands = 5.56 millimetres (0.219 in), Ø grooves = 5.59 millimetres (0.220 in), land width = 1.88 millimetres (0.074 in) and the primer type is small rifle.
According to the official Commission Internationale Permanente pour l'Epreuve des Armes à Feu Portatives (C.I.P.) guidelines the .223 Remington case can handle up to 430 megapascals (62,366 psi) piezo pressure. In C.I.P. regulated countries every rifle cartridge combo has to be proofed at 125% of this maximum C.I.P. pressure to certify for sale to consumers. This is equal to the NATO maximum service pressure guideline for the 5.56x45mm NATO cartridge.
The SAAMI pressure limit for the .223 Remington is set at 379.212 megapascals (55,000 psi), piezo pressure.
理解了吧,125%的膛压,当然增加枪械磨损。。。。。。
而弹壳外型上,.223和5.56就是一种东西。。。。。 |
|