Temperature Question

[aaroncarp]

I have spent some time this summer on here asking for advice to develop a mag fit load for my 300 RUM that shoots well. Finally found one the other day (210VLD, 92 grains of retumbo, 3.675" OAL) Anyways, I have a couple of questions because the day that the load shot about a half inch it was probably 75 or 80 degrees out. I gave the barrel 5 to 10 minutes for cooling between shots and what not.

1. Will I see much difference in grouping when Im hunting below 40 degrees?
2. Should I wait until it cools off to shoot it through a chronograph?

I have heard that retumbo is very temperature stable, but I am not sure.
Thanks

 

[FearNoWind]

It's temperature stable. Work up a load at about 80 degrees F and enjoy the hunt anywhere between 32 and 110 degrees.

 

[aaroncarp]

Awesome, I will just do some more fine tuning with this load and hopefully after another trip or two to the range I will have a good hunting load.

Thank you

 

[CB11WYO]

It's temperature stable. Work up a load at about 80 degrees F and enjoy the hunt anywhere between 32 and 110 degrees.

Yup Yup ^

If you were still worried you could go out on a cool 40-45 degree morning and shoot at distance to document the changes, if any

Same powder I use in my hunting rig btw

 

[flashhole]

You got your answers in the previous posts. Retumbo, like many Hodgdon Extreme Powders is very stable over temperature. Shoot it with confidence that the results you established during load development will work under a wide range of temperatures.

Don't get complascent about load work development based on your good experinece with Retumbo. Not all powders are this stable. I have had a bad experience with Winchester powder and my 223. Never want to go down that path again. It made a huge impact on me and I switched exclusively to Hodgdon Extreme powders.

 

[trebark]

Glad to see you've got a load worked up. I remember when you posted a thread asking for load data.

Previous posts on temp stability of Retumbo are correct. Use the Hodgdon Extreme powders with confidence for temp stability.

 

[Hunter66654]

I worked up a load (185 grain Berger hybrid, 70 Gr RL 22, Fed 215 primer) for my 300 wsm that is very accurate and gives 3005 fps. The temperature was 40 degrees. Can you offer comments on the RL22 power at different temperatures versus the Hodgdon extreme powders?

 

[trebark]

I worked up a load (185 grain Berger hybrid, 70 Gr RL 22, Fed 215 primer) for my 300 wsm that is very accurate and gives 3005 fps. The temperature was 40 degrees. Can you offer comments on the RL22 power at different temperatures versus the Hodgdon extreme powders?

The Reloder line of powders is not well known for their temp stability. I cannot offer a first-hand anecdote but some friends have used RL17, RL22 and RL25 and they all report some temp sensitivity.

 

[aaroncarp]

Thank you everyone for the replies. And on your load development, if you are developing your load for hunting purposes, i feel like 40 degrees F would be about the best temperature to load develop at.