300 wsm powder

[speeders]

I worked up a few really quick loads and went to the range yesterday. I had some IMR 4350 and IMR 4831. The 4350 was ok and groups were right at 3/4 in to 1.5 inches. I started out low and worked up to max load. Max load produced the best group.

I then shot 4381. I tried 65.5 grains to start and worked up to 66.5 grains before I ran out of time. 65.5 grains produced a 0.705 3 shot group at 100 and the 66.5 gr shot 0.590. I am still gonna keep adding slowly as I am still 1.5 grains from max.

Both loads were seated to max magazine length. 2.860

My concern is these powders sound like they are fairly temp sensitive. In Alberta, I hunt from +30 C to -30 C.

Should I worry about the IMR powders. This gun is going to be set up for shooting 800 to 1000 yards.

Im shooting a168 grain BT. As far as Hogdon powder what have guys had the best luck with, h4350 or h4381?

Thanks in advance

[D.ID]

I love h4350 in mine but can not personally say how the imr compares. With h4350 from -10f to 110 it has had a little fluctuation at the high and low but it has bean very minor. From 20-90 I do not even think about it, but I don't shoot that one past 900 typically either.

[varmintH8R]

From what I have read, the IMR extruded powders are slightly more temperature sensitive than the Hodgdon Extreme powders, but not nearly as bad as your typical ball powder. I shoot IMR4350 in my 300WSM behind 168gr TTSXs, and have not seen major differences in POI. I am not shooting at 900+ yds though.

I have also worked up some loads using H4831sc. Seems to shoot OK but not as accurate as IMR 4350 in my rig.

[jfseaman]

H4350.

[.284]

I have always been able to make 300 wsm's shoot with rl19.
I have just tried h4350 and h4831sc for the temp reasons. 4350 shows pressure for me with 175's with fairly low charges but great speed where as the 4831 is compressed and a bit slower at 2950ish but very low es.
I have only crhonied rl 22 in summer and winter with a257 wby mag and found about 100 fps spread

[baldhunter]

I've shot Win.760,Relooader-17,IMR-4350,Ramshot Hunter and Reloader-22 in mine.As you can see,that is a wide range on the powder burn rate scale.Any of these powders are capable of delivering exceptional accuracy,where they stand out is when they give you both accuracy and velocity.In my 300 WSM,Win.760 does it.

[jfseaman]

H4350 is

• consistent lot to lot
• Less than 1fps per degree temp stable
• Fast: with 208 A-Max my 'hot' load is 2887fps, slow load is 2720.
• Consistent shot to shot, using my Magnetospeed chron, 5 shot strings: SD=4 for that hot load. The slower load SD=3
• Accurate: Sub-Moa out to 700yards, that's the farthest I have at the moment. 100yards does not mean much with this big bullet. My zero is 300 with 1.125 group recorded. I've improved my shooting since then.

I have 400 down the pipe, a 28" Pac-Nor sendaro.

IMR-4350 is not a good substitute for me. acceptable but not preferred.

I have tried RL17, RL19, RL22, IMR. Nothing works as well as H4350 for me. That is the same for my 260 Rem as well.

I am trying H1000 and H4831 so that I can stretch my H4350.

H1000 is only for heavies. Fast without pressure but max case capacity gets an SD=4 at 2745fps.

WAIT - I shouldn't be telling you this. It's hard enough to find H4350.