H-1000 velocity variation/air temp value??

[helidriver72]

So I've got the Shooter app on my iPhone which I really like, my question is does anybody have a fps per degree of outside air temperature increase or decrease value for H-1000?

I'm running 89 grains in my Edge.

Thanks for any input guys, I know H-1000 is an extreme powder and doesnt vary a lot but the program has this feature and I figured I should make use of it.

[BrentM]

Excellent guestion. I am using Retumbo and not that feature on my Shooter program. So far I have shot from 10F to 45F without a temp correction and the rounds have been dead on. It will be interesting to see what happens when it gets to 60 in another month or two. I have no clue what number to put in there either.

[Joe King]

I don't use as it changes things on the app more than they really change, I think your better off just ignoring that feature with H1000, Retumbo, Varget, Magnum. even rl22 is more stable than that feature allows for

Here's how it works though
sean.kndy.net/shooter/manual.php
Powder Temp - This is an optional input and should only be entered if you also entered an MV Variation. This is the base powder temperature and should coincide with your Muzzle Velocity. So as in the example in the "MV Variation" field description above, you'd put 55deg here and 2850fps in your "Muzzle Velocity" field (or you could be 57deg here and 2855fps in Muzzle Velocity, doesn't matter). Now when you run a calculation using this ammo profile, there will be an option to enter current Powder Temp. If you were to specify say 65deg for powder temp, Shooter will automatially raise your MV to 2875fps.

[helidriver72]

Originally Posted by Joe King

I don't use as it changes things on the app more than they really change, I think your better off just ignoring that feature with H1000, Retumbo, Varget, Magnum. even rl22 is more stable than that feature allows for
.

The way I understand it I can put in 1 fps per 10 degrees of air temp change if I want so I don't think it will change things more than necissary. I'm just looking for that value to input. Thanks for the reply though.

[BrentM]

I believe it is fps/degree. So you would have to input .10 to get 1 fps change per every 10 degree's.

There is a video on here where they did a temp test. They put 5 rounds in a cooler with ice and then 5 rounds on the table in the sun. I think the temp in the cooler was 30 and the outside temp was 90. They shot 2 groups of temp stable and 2 non-temp stable. Pretty sure it was gunwerks, as they use Hogdon extreme only for their rifles. Anyway, the spread on the temp stable was something like 10 fps. The non-stable was 50 I believe. Would have to search the vid section and find it.

[Joe King]

Originally Posted by helidriver72

The way I understand it I can put in 1 fps per 10 degrees of air temp change if I want so I don't think it will change things more than necissary. I'm just looking for that value to input. Thanks for the reply though.

Yea your right, I think this is more of what your looking for
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