quick question the Varminters might now the answer to;

I chronoed a 6PPC load today at around;
5°C, 300meters above sea level, 2 feet from Chrono and got a mean velocity of 3011fps & 3057fps for Lapua and Sako brass using the same load respectively. Forgot to check air pressure.

25.3gn VV N130
70gn Nosler Ballistic tip.

When I take that ammo back to Australia (leave tomorrow) and shoot it at around 100meters(300ft) in much hotter temperatures from 28°C to 40°C(100°F?) how much of an increase in MV should I expect? I have run it through an online ballistics calculator but that can only tell me how a bullet will behave in different conditions with the same MV.

Should the MV not raise also as I go into the desert? By how much?

Try this one, you can change elevation, humidity, temperature, just about any variable that you like.

http://www.eskimo.com/~jbm/ballistics/traj_basic/traj_basic.html

This is just a guess, but I would not expect much of a change at all.

I used to shoot H 335 in my .223 Remington, shot thousands of shells using that powder. I kept seeing awfull velocity swings when I checked the speeds at different temperatures.

I finally gave up on all ball powders as I had the same problem with 748 in a couple of guns.

I now shoot N 130 and can tell little or no difference whether I shoot at 40 degrees F or 100 degrees F.

My guess is you will not be able to tell the difference when you get to the desert.

Not that temperature cannot cause pure havoc in some cases. I had a friend who I loaded 7mm Rem Mag shells for. He called me all mad because the shells were "too hot". They were the same batch of shells he had been shooting for a couple of years. A little questioning revealed they had sat on the shooting bench in direct sunlight for quite some time. This was with IMR 7828.

That's what I was getting at: The ammo will be subjected to higher temperatures here(now that I'm here) than it would have been back in Italy where overnight it was goin to -10 and during the day sometimes it never got above freezing.

I'm off to go hunt the day after tomorrow, still have to go get the luggage the airline lost for me to top off the debarcle.
I'll post a report when I get back.

Express, We'll be interested in your "real world" tests as compared to the "program pojections" for your load!! I see some differences from testing at 80 degrees vs 30 degrees using the same lot of powder and bullets but it's usually not a significant difference.....meaning the loads I use for groundhogs in July will generally be the ones used for crows and coyotes in the winter!! Albeit, the 600 yard groundhogs, I take more seriously than the 250 yard crows!! GHD