Home Forums Reloading Big Game Rifles IMR Powder?

For what it is worth, most hunters will develop loads in temps closer to actual hunting season temps. Here in Oregon that may be close to 30 degrees or less. So a real significant loss in velocity is probably not a concern. However when shooting powders like IMR4350, I have noticed a 100 fps+ swing, depending on the time of the year I am shooting that load. For hunting, you'll never notice and should remain in that sweet accuracy node, if you do your load development in the fall or winter with similar temps as when you hunt. In recent years, I've tried to switch all of my loads to more temp stable powders, like H4350 for example. It has worked great at replacing IMR4350. However, I still keep IMR4350 on hand, as it has always been one of my favorite powders. When I test and develop loads, I'll always make note of the temperature when doing so:






Its funny, I still make note of the temperature even when I'm using a temp stable powder. Just how I roll and a hard habit to break.


You sound like you know what you are doing. Its especially important to make sure each new lot of bullets and powder still shoots well in your rifle. Some guys don't get that. Its all the little things that have an affect on accuracy, even hunting rifle accuracy. As you notice in the above pictures I posted, those are some of my "hunting" rifles and some of the fine tuned loads they like. A good suggestion is to buy big lots of bullets and powder, so you don't have to worry about changing seating depth or adjusting powder charge too often. Also, this is an old thread. There have been some advancements in powder even since 2008. We have a broader selection of temp stable powders to choose from, which is never a bad thing. Now if only we can start seeing it on the shelves again!!!!!!!!