cold weather load development???

[djtjr]

ok guys i know that cold weather can have a fairly substantial effect on persure etc but this weekend i needed to get out to pull the trigger a bit and wanted to build up a load for a 30 Hart that i have. My question is really this if the gun stayed relatively warm from shooting and i left the ammo in the car with the heat on (for each set i went to the car took out ammo and put it in a warm pocket away from the elements), will the fact that it was 9 deg outside really hurt the process and potentially mask dangerous presure levels? My best group was prob in the low .3s if not .2s @100 towards the high end of my buildup 78gr of RL 22. There were no presure marks or signs but it was 9 out.

What are your thoughts?

1) Is it a waste of time to do development in the extreme cold if i will not be likely be shooting or hunting in it?

2) Will my results not likely be the same as under less extreme circumstances?

2) Does the fact that the gun and ammo stayed warm BUT NOT HOT (from shooting and from being in the warm car respectively) mitigate the effect the cold would have vs being out in the cold and shot cold bore and cold ammo?

Thanks
Don

 

[Gearheadpyro]

It would seem to me that keeping your elements warm would help with the load development, but I still wouldn't trust it without checking it out when it got a little warmer.
That being said, I have absolutely no experience shooting in 9 deg temps.

I have 2 loads for each of the bullets I use, one is for over 60 the other is for under. In coastal sc the lowest I ever really shoot in is 30ish, the highest is nearly 100. Having two loads gives me the opportunity to go shoot whenever without a new load development.

 

[alf]

Don,

I do the same thing. In fact yesterday, I was working on a new load for my 17 Rem with some new 29 gr. Kindlers. Temp was around 15. I have in the past pre-loaded for the bigger stuff at home when using stick powder, but yesterday I just took H-414 & H-380 and used my Sinclair measure in the truck to dump the powder charges, and seat with my Wilson die using my arbor press. I started the truck a couple of times and kept it around 70 inside. For me the results are valid temperature wise. More so with this one, as it's my fox/coyote gun which probably won't be used much, if any, beyond the 70 degrees.

These guys that don't have four seasons don't know what what they're missing. ;D

 

[jo191145]

JMO Some folks claim its the exterior temp that changes the load. Others claim its the ammo temp. I'm not smart enough to know myself. by keeping the ammo warm your hedging your bets anyway.
I do know this. If you can find a set of components that will shoot well in the cold in your gun.
You have a great place to restart in warmer temps.
I've seen particular sets of components shoot well in the summer. Go well below freezing and they no longer work in any configuration.