US2234165A - Projectile - Google Patents

Description

I March 11,1941. J. s. HATCHER :rm.

Inventors Julian 5 Hat|:her John E-Gray BMW M Attorney Patented Mar. 11, 1941 PRoJEoTiLn Julian Hatcher, AnnapoliavMd and John 1C.

Y Gray, Washington, D. O.

I iptiicaasoaoba 31, 1939, Serial No. 302,130

1 ilOlaims. (01.102-26) (Granted under the act of March a, .1883, as

amended April 30, 1928; 370

The invention described herein may be manufactured and used by or for the Government for governmental purposes, without the payment to us of any royalty thereon. l

l This'invention relates to a projectile, and more especially to high velocity long'range bullets.

The main objects of the invention are the production of a projectile which will offercomparatively small frictional resistance to starting motionl and travel through a gun barrel thereby permitting the use of larger propellent charges without dangerous increase'in' the gas pressure within the barrel with consequent higher velocity of projectile travel, and the formation of such projectile in a manner to permit proper air flow thereby to the end that proper exterior ballistic characteristics will be maintained.

The foregoing objects are attained broadly by decreasing the area of contact of the projectile with'the lands and grooves of the gun barrel, and by directing the air stream by the bullet in a manner to avoid contact thereof with projecting air resisting surfaces of the projectile.

More specifically the projectile includes a body whose diameter is no greater than the diameter across the lands of the barrel and it is provided with bands to take the rifling, the bands so situated as to properly balance the projectile in its travel through the barrel and seal the bore in such a manner that the maximum efiect of the propellent powder gas will be obtained with a minimum erosion. The head of the projectile has an ogive selected to cause the air stream to be defiected beyond the external diameter of the bands.

The specific nature of the invention as well as other objects and advantages thereof will clear- 1y appear from a description of a preferred embodiment as shown in the accompanying drawing in which:

Fig. 1 is a longitudinal sectional view of the improved projectile.

Fig. 2 is a longitudinal sectional view of another form of projectile.

Referring to the drawing by characters of reference:

The projectile comprises a cylindrical body 5, a base 6 which is herein shown as cylindrical but which may be boat-tailed, an ogival head I, and front and rear hands respectively 8 and 9 which occupy positions at the ends of the body. The projectile has a length which is approximately four and one-quarter times the maximum diameter which is at the bands 8 and 9.

The body 5 is cylindrical and has a diameter less than one caliber so that it will be clear of the lands of the rifiing. The length of the body is substantially the same as its diameter.

The bands Band 9 which provide engagement with the rifling for the purpose of rotating and centering the projectile have a diameter sub- 5 stantially equal to the diameter between the bottoms of opposite grooves of the rifling. The width of the front band 8 should be .04" to .05 for a .30 caliber projectile while'the Width of the rear band is approximately .03". The positioning of the 10 rear band slightly more than one-quarter caliber from the rearend of the base produces the optimum form for reduction of air resistance. If the band is placed closer than one-quarter caliber to the rear end serious air resistance will be encountered and the stability of the projectile in flight will be impaired.

The rear face of the projectile is recessed in the form of a cone or cup ill the greatest depth of which lies on the longitudinal axis of the bullet and is approximately one-quarter of a caliber in depth. This provision reduces the drag of the air on the base of the projectile during flight.

The head I is from two and one-half to three calibers in length and the curve of the ogive is of from seven to nine calibers radius. The curve when projected is tangent to the periphery of the band 8 and is receding from the longitudinal axis of the projectile at the rear of the head and adjacent the front band 8 so that the air stream passing over the ogival head will clear the front band and thereby reduce air resistance.

Referring to Fig. 1, the ogive terminates short of the front band 8 to provide a cylindrical portion II at the rear part of the head which has the same diameter as the body 5.

In the form shown in Fig. 2 the ogival head I2 merges with the front band portion [3.

The rifle in which these bullets are to be used may be equipped with any standard form of rifling it being necessary only to assure suflicient bearing surface on the driving edge of the lands to prevent stripping or shearing of the bands, which may be accomplished by deeper rifiing or an increase in the number of lands. The rifiing may, if desired be continued through only a portion of the barrel sufiicient to give the bullet a proper spin about its longitudinal axis and the remainder of the barrel toward the muzzle may be smooth.

Experiments with these bullets show an extremely high velocity with proper ballistic characteristics, and further indicate that the recess in the base of the bullet reduces the drag on the bullet at these high velocities.

While the bullets herein shown are represented as solid, it is to be understood that the same may be jacketed, and have a metal core in the well known manner, the jacket in such instance being somewhat heavier than the usual jacket at present in use.

We claim:

1. A projectile including a body portion substantially one caliber in length and having a diameter less than one caliber, band portions at the front and rear of the body portion and having a diameter greater than one caliber, an ogival head portion forwardly of the front band portion, said head portion having a length of two and one-half to three calibers and an ogive of from seven to nine calibers radius the projection of which is tangent to the periphery of the front band portion.

2. A projectile including a body portion substantially one caliber in length and having a diameter less than one caliber, band portions at the front and rear of the body portion and having a diameter greater than one caliber, an ogival head portion forwardly of the front band portion, said head portion having a length of two and one-half to three calibers and an ogive of from seven to nine calibers radius tangent to the periphery of the front band portion.

3. A projectile including a body, a narrow rotating band at the forward end of the body, and an ogival head with its rear terminus forward of the band, the curvature of the ogive when projected being tangent to the periphery of the band.

4. A projectile including a body, a rotating band at the forward end of the body, and an ogival head of from seven to nine calibers radius, the curvature of the ogive being tangent to the periphery of the band.

5. A projectile including a body, a rotating band at the forward end of the body, an ogival head terminating short of the band, the curvature of the ogive when projected being tangent to the periphery of the band, and the portion between the band and rear terminus of the ogive having a diameter substantially the same as the diameter of the body.

6. A projectile including a body portion and an ogival head portion of from seven to nine calibers radius, the curve of the ogive tangent to a cylinder having. a diameter greater than the diameter of the body whereby the rear portion of the head constitutes a rotating band, and a rifling band on the rear portion of the body portion.

'7. A projectile including a body substantially one caliber in length and having a diameter less than one caliber, a base in rear of the body, a band portion between the base and body and substantially one-quarter of a caliber from the rear end of the base, a band portion at the forward end of the body, and an ogival head having a length between two and one-half and three calibers and a curvature based on the forward band portion.

JULIAN S. HATCHER. JOHN C. GRAY.

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