.366 | 255gr | Geco EXPRESS

About this bullet

.366 | 255gr | Geco EXPRESS is a bullet made by Geco. At 255 gr (16.5 g) and a diameter of 0.366'' (9.30 mm) it suits handloads where bullet weight and barrel length have to be matched carefully. Its G1 ballistic coefficient of 0.398 drives velocity retention and wind drift downrange — higher values mean a flatter trajectory at distance. A twist rate of 1:6.0 is recommended for stable flight; slower twists can under-stabilise this bullet. We currently list 347 load recipes across 6 calibers for this bullet.

Most popular calibers for this bullet

Load data for .366 | 255gr | Geco EXPRESS bullet is available in the following calibers:

• 9.3 RSM
• 9.3 x 57
• 9.3 x 62
• 9.3 x 64 Brenneke
• 9.3 x 66 Sako
• 9.3 x 74 R

Safety notes

All load data is reference data only. Always start at the minimum charge and work up in small steps while watching for pressure signs. Never exceed the maximum charge published by the powder or bullet manufacturer.