H4831 Temperature Sensitivity

[Red Mule]

For a long time, my favorite load for .270 Win has been the Sierra 140 gr BTGK with IMR 4831. IMR 4831 has been hard to find locally so I bought a pound of H4831 to work with.

In the past, I found that IMR 4831 was temperature sensitive and the loads that I developed and shot during the summer and early fall, were very anemic once the weather got cold, and the loads that I could shoot in the cold weather were too much when the weather was warmer. I just learned to adjust.

I have been using Varget in a couple of .308's and .223 and it does not seem to be as affected by temperature. Is there any real world experience with H4831 that would indicate that it is less sensitive than IMR 4831?

 

[jasonk]

Re: H4831 Temperature Sensitivity

According to Hodgdon it's less sensitive.

Our exclusive line of extruded rifle powders – Hodgdon Extreme™ – was developed to give shooters consistent performance, load after load, in even the most extreme heat and cold.

It is probably safe to say more big game has been taken with H4831 than any other powder. Bruce Hodgdon was the first supplier to introduce this popular burning rate in 1950. Since that time it has become a favorite for cartridges like the 270 Winchester, 25-06 Remington, 280 Remington and 300 Winchester Magnum. As an Extreme Extruded propellant it shares the fine quality of insensitivity to hot/cold temperatures, as well as superb uniformity from lot to lot.
H4831SC - Ballistically, this Extreme Extruded powder is the exact copy of H4831. Physically, it has a shorter grain size, therefore, the designation SC or short cut. The shorter, more compact kernels allow the powder to flow through the powder measures more smoothly, helping to alleviate the constant cutting of granules. With the smoother flow characteristics comes more uniform charge weights, while the individual grains orient more compactly, creating better loading density. Available in 1 lb. & 8 lb. containers. Take the Extreme Tour.

 

[marc.soileau1]

Re: H4831 Temperature Sensitivity

When I started reloading IMR 4831 was one of my go-to powders because I was reloading for the 270 WIN and 243 WIN. I got very good accuracy out of the powder. Because these were for stock hunting rifles, the effects of temperature were negligable.

I have since switched to H4831 for my 270 WIN as my go-to powder with the same great accuracy. The powder is more temp sensitive, but is not as critical in a mid-range stock hunting rig. At the same time - every little bit counts.