300 Win Mag & Unique?

[ShooterAZ]

I'm considering loading up some cast for my Ruger 77 MkII 300 Win Mag. I haven't tried any cast loads in it yet, but I want to put together a trial load to see if it will shoot cast well. Bore slugs .308, sizing to .309. The load I am considering is 18 grains of Unique over the Lee 30 cal 170 flat point gas check, lubed with 2500. Any opinions on this? I just want to try a mild load at first. I have plenty of other powders, including 2400, SR4759, IMR4895, IMR4064, IMR4198, and many, many more.

Am I on the right track for a starter load? Any other suggestions?

Thanks...Shooter

[Ben]

Contact Pat Marlin.

He shoots ( accurately I might say ) cast in the .300 Win. Mag.

[ShooterAZ]

Thanks Ben. I went ahead and loaded up the 18 gr Unique and the Lee 170F per my original post. My results were....OUTSTANDING! My first five shots from a clean cold barrel were all touching at 50 yards. Moving back to 100 yards the groups opened up to 1-1/4". Clearly my rifle will shoot cast well. I'm looking forward to experimenting with more powders & boolits.

From the amount of replies to my initial post I would gather that not many shooters cast for their 300 Mags, or there is little interest in doing so. This was fun and rewarding! My next powder to try will be SR4759. With a little luck, maybe it will shoot as least as well as my first load.

Shooter

[TCFAN]

I just now came across this thread. A few months ago I bought a used but like new Encore frame and it came with a 300 win mag 26 inch heavy barrel. I really did not want a 300 but I thought that since I am a boolit caster it might be something to play with.

I have tried a few different boolits with the most accurate being the Lee 312-155.The one with the regular lube grooves.I have also tried the RD 311-170.The one thing I have noticed is that I can not push these boolits much faster from the 300 than from a 30-30.

So I am going to learn how to paper patch. I have tried some but have a log way to go before I really know what I am doing.

I wish you good luck with your 300 win mag and cast boolits..............Terry

[ShooterAZ]

Terry,

I have the Lee 312-155. I use it in my 308's and 06's. I will try that one. 30-30 velocities are fine by me...as long as accuracy is good!

[TCFAN]

I couldn't complain about the accuracy with the Lee 312-155 I just wanted more velocity than a 30-30 gets.Paper patching give the velocity but as of now the accuracy is not there.I am doing something wrong but I don't know what....Terry