In a pitot-tube, a small filament of the fluid is brought to rest in a small-bore tube, the impact pressure being measur在全压管内，注入的液体流丝停留在一个小内径管内，全压通过外管内液体的静压测得。
To achieve necessary high penetration while keeping recoil impulse low, FN used a small-bore approach, creating a round 要达到高渗透在保持低反冲冲动,新生力量用小口径办法创造一个回合,就如同雏5,56北约轮.