公开(公告)号：US07802394B1

公开(公告)日：2010-09-28

申请号：US11899647

申请日：2007-09-07

Applicant: David John Bartoli

Inventor： David John Bartoli

IPC: F41A21/00

CPC classification number: F41A21/18

Abstract: A rifle having a rifled barrel and a cartridge having a bullet having a diameter, a length, a ballistic coefficient (BC), and a muzzle velocity (V1) greater than 1250 ft/sec are related to achieve accuracy at very long range in that the twist of the rifling is substantially equal to: 83.7 ÷ ( bullet ⁢ ⁢ ⁢ length × 2 ⁢ B ⁢ ⁢ C bullet ⁢ ⁢ diameter ) × bullet ⁢ ⁢ diameter × [ 1 + ( V 3 V 1 × 0.667 ) ] where: V2 is the entry speed for the transonic, i.e. 1,250 ft/sec., and V3 is V1 minus V2. A rifle barrel for receiving a bullet has rifling twist according to the relationship. A method uses the relationship to determine the rifling twist for a rifle barrel receiving a known bullet. Another method uses the relationship to design a cartridge for a known barrel rifling. The relationship is particularly applicable for bullets having a high BC, such as 0.325 or greater.

Abstract translation: 具有膛线枪的枪和具有直径，长度，弹道系数（BC）和大于1250ft / sec的枪口速度（V1）的子弹的药筒都可以在非常长的范围内实现精确度，因为 膛线的捻度基本上等于：83.7÷（bullet？⁢长×2B⁢C bullet ud直径）×bullet通径×[1 +（V 3 V 1×0.667）]其中： V2是跨音速的输入速度，即1,250英尺/秒，V3是V1减去V2。 根据关系，用于接收子弹的步枪枪具有膛线扭转。 一种方法使用关系来确定接收已知子弹的步枪枪的膛线扭转。 另一种方法使用关系来设计用于已知筒枪的筒。 该关系特别适用于具有高BC的子弹，例如0.325或更大。