V0 for cold and warm ammuntion

I've stressed that one needs to chronograph the loads all through the year and different temperatures if one wants to shoot properly longrange at unknown distances. THAT IS MORE OR LESS A CRITICAL ENABLER.

This data gathering takes some time. In this film I tried a little experiment too see if I could manipulate the ammunition temperature and match my already logged velocities.

I consider this a failed experiment as there was too much delay in the cartridge mass for me to say anything useful about the ammuninition temperature. I got ok velocities for the cold ammunition, the warm ammunition was a little harder to determine. It gave a maximum velocity indication but I could link it with sufficient accuracy to a temperature so this data could be of actual use.

The velocity variation between cold/ warm temperature is unavoidable, just make sure you don't get irregular performance at the higher and lower temperatures - accuracy must be the same through the temperature zone you shoot. The V0 change will be from 0,5 msec to 1,3 msec pr 1 Celsius, the most commong seems to be right around 0,7-0,9 msek per 1 Celsius

Here's the experiment Chronographing cold and warm ammunition

Good info there Norway, I keep my LR ammo in my pocket all year 'round. This solves the issue for me completely.

Too cold here for that. I'll get a cartridge in temperature/V0 freefall should i do that, it being somewhere between pocket and ambient temperature. It would ruin my accuracy.

Im glad its not that cold here, I hunted both days in the weekend and Saturday was a lovely 1.7 deg celcius all day, I got 2 Red Stags at 550yrds with the Rem Mag/A-Max combo, Sunday had the better frost but got up to 5deg c in the middle of the day. The old ammo in the pocket trick works at these temps.

But not to detract from the topic of your thread, I think checking the velocity of ammo at different temps is a very good idea.

Nah bring it on, no distractions there. It is good to introduce people to several solutions.

I was trying to say "couldn't link". I think if I built a small brick box that would delay the heat enough to properly heat/control the ammo temp. Put a wire thermometer inside a sandfilled case?

So Norway what are your views on different types of power then in cold and hot conditions ie: ball powder, single base, double base, when your talking about accuracy and velocity at long range?

No idea. I use Norms MRP exclusively. It works, I stick to it.