I thought I'd better start a new thread and not hijack the other one going.

My question is how are temperature insensitive powders made? Are they designed that way or is it a lucky coincidence? What manufacturing process allows some powders to not be affected by temperature where other powders are?

Couldn't tell you details but one part is generally to start with stick powder.

Probably there are more stick temp-resistant powders than spherical, but there are also a bunch of sphericals, some of which aren't advertised as temp-resistant. One is Ramshot Big Game, which in my testing over the years in a lot of different cartridges has proven as temp-resistant as any of the Hodgdon Extremes.

I don't know much about the technical aspects of producing temp-resistant powders, because powder companies understandably tend to be very reticent to discuss their manufacturing techniques, especially to gun writers who might write about them publicly.

But did indirectly hear of one technique, from a powder distributor who'd visited a major powder factory. The folks there told him that flattening the granules of spherical powders (which they called "laminating") made them more temp-resistant--but also less accurate.

Thanks for the replies. So maybe the shape of the powder kernals does something to the burn consistency? I thought it would be more to do with chemical makeup of the powder.

But probably something we'll never really know.

single base powders are normally more temp stable than double base powders due to the nitroglycerine in double base powders, however the double base powders have aa lower flame temp. at max pressure, but they tend to burn dirtier at less than max pressures.

I am sure there's some chemistry in there as well, probably in the powder coatings.



That tended to be true a few years ago, but are plenty of very temp-resistant double-based powders these days, both spherical and extruded.

Wrong! It isn’t stick or ball.

https://ndiastorage.blob.core.usgovcloudapi.net/ndia/2013/IMEM/W15931_Vogelsanger.pdf

2013 manufacturing change by RUAG and NAMMO.

But the EI powders are double base powders, single base does not contain nitroglycerine, all double base powders do.

Those constructing their Christmas rocket ship may find this info...useful.