Powder charges VS Outside temperature ?

[willyp]

Has any one ever done a study of just how much the difference of the temperature outside affects the loads that we shoot ?
I would imagine a Chronograph would be the best thing to use with out having a bunch of special equipment ?  RIGHT ?
But how do or can you plan for cold weather such as Deer season temps ?
I have used the Hogdon  powders that are supposed to be unaffected by temps but seen very little difference ?

[davet]

All I can say is I use Varget in my .308. That powder is suppose to be stable across a wide temp fluctuation. I just take their word for it....I don't have the "want" to bench rest it at 15 degrees!!!

[Muab Dib]

I've chronographed at 95 degrees and 28 degrees and with my old school IMR powders there is a very real difference (lower) in velocity at really cold tempts. Not enough for me to miss what I'm shooting at; but the difference can be upwards of 75-100 fps lower. Just my observations. I like the IMR powders enough not to worry about it.

Muab

[Deleted]

I know it makes a difference but I just never cared. In the PA woods 100 yards is a long shot. Being short 50 ft a second just ain't gonna matter.

[Loggy]

Never noticed significant variances with smokeless powder but a different story with saboted black powder loads. Extreme cold temps reduces velocity in saboted inline loads per my chrony tests.  I have found that the newer formulated polymer based sabots available from MMP has reduced the temp impact on velocity.

[dougell]

tHERE CAN BE A BIG DIFFERENCE,ESPECIALLY WITH BALL POWDERS.

[davet]

If you go to Hodgdon's web site they list what I think they call their "extreme" powders. Those are made to prevent big swings in temp's from effecting the POI of your loads.

[dougell]

That's what I use for the most part and it works as advertised.I use a lot of varget and H4350.