28/01/2019 | Hints from the experts

Temperature coefficient

Dear reloaders,

We make every effort to ensure that our powders are as temperature-independent as possible. However, in spite of all our efforts, it is not absolutely possible to represent a uniform performance independent of temperature. In general, pressure and velocity increase as a function of temperature. It is useful for you to know how much additional performance you can expect from an increase in temperature so that you can correctly adjust your sights beforehand. Naturally, this change depends on the overall configuration (calibre, primer, propellant powder, projectile). The propellant is just one part of the overall effect. In spite of that, with the table shown here we seek to present a reference value for the temperature coefficient of long-arm powders. In our analysis, we extrapolated the hot and cold from the measured velocities on a linear basis. The values given here are mean values from different product lots. We are aware that temperature coefficients determined individually are significantly more precise. Still, we hope that this table provides some orientation. I wish you perfect hits at any temperature.

Type Calibre Temperature coefficient
m/s pro K
RS36 7.62mm x 39 0.60
RS40 .223 Rem 0.45
RS50 .308 Win 0.70
RS52 .308 Win 0.55
RS60 8 x 68 S 0.25
RS62 .270 Win 0.90
RS70 .300 Win Mag 0.45
RS76 7mm Rem Mag 0.20
RS80 .338 Lapua Mag 0.20

Urs von Mühlenen

The perfect hit!
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