Summer Testing For Winter Nights

[allrounder]

Say I develop a load in May or June, would leaving ammunition in the fridge over night be a viable way to test wether the same load will shoot well on a cold winter's night?

 

Is the main factor powder temperature/burnrate, or are there too many other factors like barrel temperature, air temperature, humidity etc. to be taken into consideration also.

[DaveT]

Its a good idea I guess as low powder temperature will be the main factor affecting MV.... although I have no idea what fridges typically produce temperature-wise.

 

The other option is simply to use a ballistic app to predict MV variations caused by current vs prevailing temperatures on a given day.

 

Optionaly just keep your mag in your pocket (warm) until you expect a shot.... might be cumbersome!

 

I would load develop as normal and then see if the expected drop in temperatures during Winter usage over the range that you expect to shoot at actually creates a significant amount of bullet drop due to lowered MV....probably not unless you shoot at extended ranges.

[brown dog]

I think the fridge idea is a good one, 'ammunition conditioning' - needs to be in there for at least 24hrs, and then kept at that temp until fired (coolbox with thermometer?) and then fired almost as soon as it's removed from the cool box so that it has no time to warm to ambient.

 

 

The other option is simply to use a ballistic app to predict MV variations caused by current vs prevailing temperatures on a given day.

 

Dave, I don't follow the various ballistic apps; which ones are offering MV change due to temp? Last time I looked at any(2+years) they all just did the effect of the colder air on the bullet's flight, but didn't do anything to MV due to lower charge temp. Only thing I'm aware of that does that is loadbase?

[DaveT]

Brian Litz app shows MV variations based upon powder temperature as well as ambient air temp... seems VERY accurate overall.

[brown dog]

Brian Litz app shows MV variations based upon powder temperature as well as ambient air temp... seems VERY accurate overall.

 

Thanks, just googled that and had a read. I see you have to put in your own temp calibration (fps change per deg C) for your load. That's exactly how I attack it.

I thought you meant the app had each powder calibrated against temp; ie input powder brand and get a result (which caused my jaw to drop! ).

 

If you have any empirical data, it'd be great if you'd add it to this thread: http://ukvarminting.com/forums/topic/12687-powder-mv-change-with-temp/?hl=temp

[Crosshair]

This guy tries it: