Load data for .38-55 Win. + 240gr Rim Rock RNFP Cowboy

34 suitable loads across 8 powder(s) for cartridge .38-55 Win. with 240gr Rim Rock RNFP Cowboy bullet.

The most recommended powders for this combination are ADI AR 2207, Vihtavuori N120 and ReloadSwiss RS 14.

Based on C.I.P., the max. allowed case length is 2.085 in / 52.96 mm, the max. cartridge length is 2.510 in / 63.75 mm, and the max. allowed pressure is 34,809 PSI / 2,400 bar.

Load Specifications

ImperialMetric

Bullet:.38 | 240gr | RNFP Cowboy

Cartridge:.38-55 Win. load data

Case Length (L3):2.085" | 53.0 mm

Cartridge Length (COL/L6):•••

Seated Depth:0.480" | 12.2 mm

Case Capacity:52 gow | 3.37 cm³

Primer Size:Large Rifle (LR)

Max. Pressure (C.I.P.):34,809 psi | 2,400 bar

Barrel Length:20.0" | 508 mm

Min. Twist Rate:Stabilizes in any common twist

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Community Loads for .38-55 Win. + 240gr Rim Rock RNFP Cowboy

Real loads for this combination shared by our community. Charge weights are only fully visible with an active Pro licence.

Charge (gr)	C.O.L.	Barrel Length	Velocity (fps)	Pressure (psi)

30.3 gr	2.515"	24.0"	1838 fps	•••

29.8 gr	2.515"	24.0"	1806 fps	•••

Charge weights beyond the first rows and all pressure values are only visible with an active Pro licence.