mounting man

Have you ever worked on a load for a certain rifle,only to find that as it got cooler or warmer outside,it fell apart??????
Do you keep track of the temp every time you go shooting? It would be so nice to have a powder/load that stayed the same?
What do you do?

edmehlig

I've been using H4831SC powder for years for my 280 and 270 rifles . The reason why I switched to H4831SC is their advertisement years ago stated this powder was not impacted by change of temperature. While I'm no expert, I have not seen a change in impact/size of my groups while shooting during the summer or winter.

BCRules

I had alot of trouble with alliant reloader powders over temp variations. And also issues with IMR4350. Shot the other day, I wouldn't say the load fell apart, but I had heavy bolt lift at 80F. I didn't at all at 30F.

mounting man

Thats what i'm talking about!!!!!!!!!

BCRules

I can only say what powders I have had issues with. I use Retumbo, H1000, H4831SC, and Varget and none have I had this issue. Doesn't mean they don't have it.

Wayspr

What type of temp range do you normally see a difference if you're going to? A spread of 50 degrees, 40, 30? I'm using IMR 4350 in a 257 Roberts that accuracy has gone to hell in for no apparent reason. Only real change is warmer temps but only in the range 20-30 degrees.

BCRules

Well, I hate building up loads in 90F summer. Most people I know do alot of range time in the winter/spring for loads. So most I build up is 30-40F. So your talking 50 degree swing easy.

mounting man

I did more reading,on this and a few long range shooters have said that IMR powders are the most guilty of the temp change/accuracy change! The thing stated was that Hodgon powders were more temp stable but not perfect! If powder ever comes on the market,again,i will try some?
A second thing,i was told,is, to carry my rounds to the range in an ice chest on ice!!!!!Then only take them out,one at a time and shoot them before they warm up? Seems like it may work,so i will try this soon! Have any of you tried the ice chest thing?

Wayspr

For years I have avoided load development in summer because my rifles see hunting use in colder temps. This year I have been doing load work at sun-up but recently ran into issues in the above mentioned 257. I may try loading some that shot good in cooler temps and bring to the range in a cooler.

emtrescue6

I had a great deal of issues with RL 19 due to temp variations a few years back and no longer use any of their powders because of it. I use H4350, IMR4895, H4831sc, H4831 and W748 for just about all of my loads now days and have not experienced any issues due to temp. I will say though that I have done most of my load development during the spring over the years and hunt mostly in the fall when temps are mild...but have hunted in temps over 90* and below -20* with loads developed in the mild spring temps.