I picked up a Ruger 77 mk 1 in .300 WinMag and am starting to reload for it. I will be using IMR 4350 and 7828 for powder Winchester and Federal cases. I have some CCI large rifle primers but I wonder if it would be better if I picked up some Federal 215 magnum primers??
.300 Win Mag
- Thread starter Cole
- Start date
I like mag primers for 300 win mag. If you don't know already, there are huge differences in case capacity between brass brands for the 300wm. I haven't used 7828, but I would have to think imr4350 would be a tad fast for typical 300wm projectiles.
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Try to find a manual with pressure tested data that doesn't use magnum primers in magnum rifle cartridges. I dare you.
4350 is the classic powder for magnums. In the past...30 or 40 years there have been lots of advances. 4350 works just fine, but you can do way better. My dad who has been reloading since the dawn of time always has that 4350 as his go to for his weatherby's etc because it was the go-to when he started. Now with RL 22 and 25 or imr 7828 or retumbo it's outshined. It works as well as it ever did, but just there are new stuff that works better.
I can get a bit more speed with H1000 than IMR4350, but its not a huge amount. One thing that I've noticed is that that 100 fps and 10 grains less powder makes a big difference in recoil. Its enough to make it or break it for someone on the edge of their tolerance.
I have been reloading & playing with the .300 win mag for 22 year's. My trusted & beloved model 70 chambered in .300win mag is on it's 9th barrel. Although I do not claim to be a expert by any mean's. I would highly recommend using a magnum primer with any magnum case ,especially the .300 wm.
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I am very fond of Reloder 22, IMR 7828, Norma MRP and Vihtavuori N165 in my 308 Norma Magnums, which, essentially are ballistic twins to the 300 Win.
Any of these will drive a 180 grain bullet to 3100 fps, and a 200 to 2975+
That being said, one of my Norma Mags prefers Reloder 25 with the 200 Partition, so I use a big load of that in it.
Regards, Dave.
Any of these will drive a 180 grain bullet to 3100 fps, and a 200 to 2975+
That being said, one of my Norma Mags prefers Reloder 25 with the 200 Partition, so I use a big load of that in it.
Regards, Dave.
Some very good powder suggestions by some very knowledgeable & respected reloaders.
My two .300 win mag's with their 28in Pacnor barrels just love the 215gr Berger hybrid's with a stiff powder charge of H-1000 & GM215M primer's.
Both rifle's are pushing the bergers around 2950fps,
Looking back over my note's I see my HS precision with a 24in factory barrel really liked IMR-4350 with the lighter bullets & showed promise with 7828 with the 210gr Berger's. And the model 70 with a 26in factory barrel showed very similar result's as the 24in barrel mentioned earlier. But with better result's with the heavy's & 7828. But once again I strongly suggest a mag primer. Good luck & please keep us posted with your proven result's & congrad's on the Ruger & the venerable .300 win mag.
Cheer's
My two .300 win mag's with their 28in Pacnor barrels just love the 215gr Berger hybrid's with a stiff powder charge of H-1000 & GM215M primer's.
Both rifle's are pushing the bergers around 2950fps,
Looking back over my note's I see my HS precision with a 24in factory barrel really liked IMR-4350 with the lighter bullets & showed promise with 7828 with the 210gr Berger's. And the model 70 with a 26in factory barrel showed very similar result's as the 24in barrel mentioned earlier. But with better result's with the heavy's & 7828. But once again I strongly suggest a mag primer. Good luck & please keep us posted with your proven result's & congrad's on the Ruger & the venerable .300 win mag.
Cheer's
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My criteria for Standard vs Magnum primers is:
60 grains or more of extruded powders = Magnum primer.
50 grains or more of Spherical powders = Magnum primer.
Hunting in weather that may drop below -20ºC = Magnum primer.
Magnum primers also vary in their strength, so it is good to keep that in mind. WLRM and Fed 215 are the hottest, FWIW.
It is not discreet to switch to magnum primers in any load without backing down a bit and working up again, using a chronograph.
Regards, Dave.
60 grains or more of extruded powders = Magnum primer.
50 grains or more of Spherical powders = Magnum primer.
Hunting in weather that may drop below -20ºC = Magnum primer.
Magnum primers also vary in their strength, so it is good to keep that in mind. WLRM and Fed 215 are the hottest, FWIW.
It is not discreet to switch to magnum primers in any load without backing down a bit and working up again, using a chronograph.
Regards, Dave.
I'm no expert but mostly depend on the bullet weight, how many fps he push that lead out of the barrel and barrel contour play a bit different ? Honestly, rebarrel every 2.5 years is quite a lots if it's for a regular hunting rifle.
4350 is a good powder. It won't get top velocity, but in some of my 300s, it is best accuracy.
A mag primer won't hurt and it is excellent insurance for that cold weather shot you might take one day.
7828 has a heavy deterrent coating of DNT* and a mag primer is called for.
*DiNitroTolulene Not to be confused with TriNitroTolulene (TNT)
A mag primer won't hurt and it is excellent insurance for that cold weather shot you might take one day.
7828 has a heavy deterrent coating of DNT* and a mag primer is called for.
*DiNitroTolulene Not to be confused with TriNitroTolulene (TNT)
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