Load data for .257 Roberts + 87gr Speer TNT

Based on C.I.P., the max. allowed case length is 2.233 in / 56.72 mm, the max. cartridge length is 2.775 in / 70.49 mm, and the max. allowed pressure is 51,488 PSI / 3,550 bar.

Based on C.I.P., the max. allowed case length is 2.233 in / 56.72 mm, the max. cartridge length is 2.775 in / 70.49 mm, and the max. allowed pressure is 51,488 PSI / 3,550 bar.

Load Specifications

ImperialMetric

Bullet:.257 | 87gr | TNT

Cartridge:.257 Roberts load data

Case Length (L3):2.233" | 56.7 mm

Cartridge Length (COL/L6):•••

Seated Depth:0.373" | 9.5 mm

Case Capacity:58 gow | 3.76 cm³

Primer Size:Large Rifle (LR)

Max. Pressure (C.I.P.):51,488 psi | 3,550 bar

Barrel Length:24.0" | 610 mm

Min. Twist Rate:1:12.0

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Community Loads for .257 Roberts + 87gr Speer TNT

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)

48.0 gr	2.780"	—	2855 fps	•••
52.0 gr	2.780"	—	3123 fps	•••

46.2 gr	2.780"	—	3317 fps	•••

•••	2.780"	—	3172 fps	•••

•••	2.780"	—	3099 fps	•••

•••	2.780"	—	2949 fps	•••
•••	2.780"	—	3273 fps	•••

•••	2.780"	—	2963 fps	•••
•••	2.780"	—	3225 fps	•••

•••	2.780"	—	2980 fps	•••

•••	2.780"	—	2797 fps	•••
•••	2.780"	—	3058 fps	•••

•••	2.780"	—	3204 fps	•••

•••	2.780"	—	2845 fps	•••
•••	2.780"	—	3097 fps	•••

•••	2.780"	—	3107 fps	•••

•••	2.780"	—	3002 fps	•••

•••	2.780"	—	3195 fps	•••

•••	2.780"	—	2863 fps	•••
•••	2.780"	—	3126 fps	•••

•••	2.780"	—	3036 fps	•••
•••	2.780"	—	2987 fps	•••

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