Temperature sensitivity

[mrjimsfc]

I have heard (is it only a rumor?) that Retumbo (Hogden) is a very temperature INsensitive powder and that regardless of the temperature of the powder in the case (cold, warm or hot) the burning rate of the powder is affected very little. How does this compare with other powders of similar burn rates?

Magnum (Ramshot) A little faster burn rate, slightly less expensive, harder to get, ball powder (easier to measure).

N170 (Vihtavuori) A little slower burn rate extruded powder.

MRP2 (Norma) A little slower burn rate, more expensive and hard to get exruded powder.

Has anyone actually made a comparison of the above (or similar) powders or know of any reliable source of information on them? All I've got so far is some guy saw a TV show once that compared Retumbo to some other powders (he didn't rember what the others were) and Retumbo showed the least variation in muzzle velocities over the change in powder temperature.

Edit: I've read the "temperature stable powders test" subject in this section but it doesn't deal with any of the powders other than Retumbo that I'm wondering about. (Well, someone <span style="font-style: italic">did</span> mention that they thought Vihtavuori is generaly temperature stable)

 

[Fuzzball]

Re: Temperature sensitivity

"Temperature sensitivity" is real but seems to be vastly over agnonised. Military .30-06 machine gun ammo works very well from low level strafing in desert heat to dog fights at altitude in -40 temps.