5.7mm Quinn

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5.7mm x40 Quinn
5.7mm Quinn variants
Place of origin Tír Glas
Service history
In service1980 onwards
Production history
DesignerQuinn Arms
Designed1969-77
Specifications
Parent case.30 Remington
Case typeRimless, tapered bottleneck
Bullet diameter0.224 in (5.7 mm)
Neck diameter0.256 in (6.5 mm)
Shoulder diameter0.402 in (10.2 mm)
Base diameter0.421 in (10.7 mm)
Rim diameter0.422 in (10.7 mm)
Rim thickness0.049 in (1.2 mm)
Case length1.600 in (40.6 mm)
Overall length2.260 in (57.4 mm)
Rifling twist190mm or 165mm
Primer typeSmall rifle
Maximum pressure55,000 psi (380 MPa)
Ballistic performance
Bullet mass/type Velocity Energy
4 g (62gr) FMJ 3,050 ft/s (930 m/s) 1,299 ft⋅lbf (1,761 J)
4.85 g (75 gr) OTM 2,815 ft/s (858 m/s) 1,443 ft⋅lbf (1,956 J)
5.8 g (90 gr) OTM 2,540 ft/s (770 m/s) 1,372 ft⋅lbf (1,860 J)
Test barrel length: 410 millimetres (16 in)

The 5.7mm Quinn is a rimless bottlenecked intermediate cartridge developed in the 1970s in Tír Glas by Quinn Arms. The round was standardised between members the Triple Entente in 1980 and latterly Vinyan Defence Community in 1990. It has since been fielded by the armed forces of Menghe, Hallia, and Dayashina amongst others.

Initial Development

The 5.7mm Quinn cartridge was designed to address the deficiencies of the SCHV cartridge being touted as a new standard for the 'western' militaries. Due to the sorts of terrain in which Glasic forces were expected to fight Tír Glas was reluctant to move to this cartridge but at the same time wished to move away from the currently issued but weighty 7mm x48. The resultant cartridge was the product of a lengthy study into possible alternatives. A major point in the study was to offer superior downrange lethality at longer ranges than the SCHV cartridge then being proposed with a minimal loss in magazine capacity and a negligible increase in recoil. To this end the cartridge would bridge the gap between the SCHV 5.56 mm and larger 7mm cartridge already in service.

During testing it was determined that a 7mm bullet although offering better terminal ballistics than the SCHV 5.56mm would not possess the performance at range required to replace the 7mm x48 without resorting to a larger case or retaining the 7mm x48. Further experiments were conducted with 6mm, 6.5mm and 5.7mm bullets, the end result was that the 5.7mm bullet was selected for further development of the long-range cartridge whilst the 7mm would go on to become the 7mm Quinn in the late 1990s. It was decided to expedite development to base the cartridge case off that of the .30, necked down to .224in (5.7mm), this resulted in increased case capacity compared to the 5.56mm x45 which in turn allowed for higher velocities to be obtained as well as seating longer, heaver, more aerodynamic bullets than possible in the SCHV cartridge. It also maximised commonality between weapons chambered in SCHV calibre, the Glasic cartridge only requiring a replacement barrel, bolt and possibly magazine.


Variants

  • Cartús, 5.7mm, Ball, Patrún 80 (P80B)
Initial pattern fielded, 4g FMJ with nickel-coated case and molybdenum-coated bullet.
  • Cartús, 5.7mm, Tracer, Patrún 80 (P80T)
Broadly as P80B but with violet tracer element in base of bullet.
  • Cartús, 5.7mm, Blank, Patrún 80 (P80E)
Blank training cartridge.
  • Cartús, 5.7mm, Drill, Patrún 80 (P80D)
Inert cartridge with fluted indentations in the case. Used for loading and unloading drills during basic training.
  • Cartús, 5.7mm, Ball, Patrún 90 (P90B)
Semi-Armour-Piercing cartridge 4.85g oa. w/. 1.25g steel penetrator .
  • Cartús, 5.7mm, Tracer, Patrún 90 (P90T)
Broadly as P90B but with violet tracer element in base of bullet.
  • Cartús, 5.7mm, Armour-Piercing, Patrún 95 (P95A)
Armour-Piercing cartridge, w/. 2g wolfram penetrator.
  • Cartús, 5.7mm, Match, Patrún 08 (P08M)
Long-range, open-tipped cartridge, 4.85g with tin-bismuth core.
  • Cartús, 5.7mm, Match, Patrún 80 (P15M)
Long-range, open-tipped cartridge, 5.85g with tin-bismuth core.
  • Cartús, 5.7mm, Ball, Patrún 17 (P17B)
Semi-Armour-Piercing cartridge, solid copper 4.85g oa. w/. 1.25g steel penetrator
  • Cartús, 5.7mm, Tracer, Patrún 17 (P17T1 + P17T2)
Broadly as P17B but with violet or infra-red tracer element in base of bullet.