.303 British

.303 British
Left to right: .303 British, 6.5×50mmSR Arisaka and .30-06 Springfield ballistic tip ammunition
TypeRifle
Place of originUnited Kingdom
Service history
In service1889–present
Used byUnited Kingdom and many other countries
Wars
Production history
Produced1889–present
Specifications
Case typeRimmed, tapered, bottleneck
Bullet diameter7.92 mm (0.312 in)
Land diameter7.70 mm (0.303 in)
Neck diameter8.64 mm (0.340 in)
Shoulder diameter10.19 mm (0.401 in)
Base diameter11.68 mm (0.460 in)
Rim diameter13.72 mm (0.540 in)
Rim thickness1.63 mm (0.064 in)
Case length56.44 mm (2.222 in)
Overall length78.11 mm (3.075 in)
Case capacity3.64 cm3 (56.2 gr H2O)
Rifling twist254 mm (1-10 in)
Primer typeLarge rifle
Maximum pressure (C.I.P.)365.00 MPa (52,939 psi)
Maximum pressure (SAAMI)337.84 MPa (49,000 psi)
Maximum CUP45,000 CUP
Ballistic performance
Bullet mass/type Velocity Energy
150 gr (10 g) SP 844 m/s (2,770 ft/s) 3,463 J (2,554 ft⋅lbf)
174 gr (11 g) HPBT 761 m/s (2,500 ft/s) 3,265 J (2,408 ft⋅lbf)
180 gr (12 g) SP 783 m/s (2,570 ft/s) 3,574 J (2,636 ft⋅lbf)
Test barrel length: 24 in (610 mm)
Source(s): Accurate Powder[1][failed verification]

The .303 British (designated as the 303 British by the C.I.P.[2] and SAAMI[3]) or 7.7×56mmR, is a .303-inch (7.7 mm) calibre rimmed tapered rifle cartridge. The .303 inch bore diameter is measured between rifling lands as is the common practice in Europe which follows the traditional black powder convention.

It was first manufactured in Britain as a stop-gap black powder round put into service in December 1888 for the Lee–Metford rifle. From 1891 the cartridge used smokeless powder which had been the intention from the outset, but the decision on which smokeless powder to adopt had been delayed.[4] It was the standard British and Commonwealth military cartridge for rifles and machine guns from 1889 until it was replaced by the 7.62×51mm NATO[2] in the 1950s.

  1. ^ ".303 British" (PDF). Accurate Powder. Archived from the original (PDF) on 30 December 2008.
  2. ^ a b C.I.P. TDCC datasheet 303 British
  3. ^ "SAAMI Drawing 303 British" (PDF). Archived from the original (PDF) on 25 December 2014. Retrieved 25 December 2014.
  4. ^ Cite error: The named reference Cushman was invoked but never defined (see the help page).