5 mm/35 SMc

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5 mm/35 SMc
5 mm/35 SMc cartridges
Type	Rifle
Place of origin	USA
Production history
Designer	Michael "Mic" McPherson and Byrom Smalley
Designed	2004
Specifications
Parent case	6 mm BR
Bullet diameter	.204 in (5.2 mm)
Shoulder diameter	.4598 in (11.68 mm)
Base diameter	.4709 in (11.96 mm)
Rim diameter	.4728 in (12.01 mm)
Rim thickness	.0157 in (0.40 mm)
Case length	1.556 in (39.5 mm)
Overall length	2.03 in (52 mm)
Rifling twist	1-12
Primer type	small rifle
Ballistic performance
Bullet weight/type	Velocity	Energy
32 gr (2.1 g) BT	4,650 ft/s (1,420 m/s)	1,535 ft·lbf (2,081 J)
39 gr (2.5 g) BT	4,250 ft/s (1,300 m/s)	1,564 ft·lbf (2,120 J)
Source: Superior Ballistics

5 mm/35 SMc is a high performance 5 mm (.20 caliber) cartridge. Designed by Michael "Mic" McPherson and Byrom Smalley^[1] and like all of their other designs carries the "SMc" moniker.

[edit] Description

SMc cartridges are an attempt to produce a more efficient cartridge. In other words, a cartridge that has low recoil, low heat, and high velocity. The 5 mm/35 SMc has produced velocities in excess of 1463 m/s (4800 ft/s) (30 grain (1.9 g) molybdenum disulfide-plated Berger bullet from a 28 inch (711 mm) Pac-Nor barrel), far higher than its commercial counterpart the .204 Ruger.

SMc cases have proven to be very difficult to produce. With the advent of the WSM case family based wildcat cartridges the SMc has ceased to be a viable high velocity cartridge.