Max of H4895 with 39gr Blitzkings?

[leojlafrog]

I've tried looking for correct data on reloading my 204 with H4895 and 39gr Blitzkings. I've noticed on the Pet/favorite loads that many people are running 27.7gr which is max for the 40gr vmax. Looking up sierra's info, they recommend a max of 26.5gr? A full 1.2gr powder difference for a bullet that weighs 1gr less seems excessive to me. Now obviously I'll have to work up my load and see what works but I'm just curious as to why such a large difference in recommendations between the two bullets. Any info would be greatly appreciated.

Thanks, Joel

[ryutzy]

Every gun is slightly different and brands of brass are different, but for my setup I start to notice pressure signs around 28 grains with the 39 sbk and H4895. I am shooting an AR so that could make a difference. My particular gun seems to shoot 27.8 grains well. Start low and work up and you will be fine.

[Silverfox]

leojlafrog --I agree with ryutzy about every gun being different and brands of brass giving different velocities too. The shape of the 40 gr. V-Max and the 39 gr. Sierra BK as well as the length of the shank are different which will probably account for some of the difference in the recommended powder charges as well. Attorneys and lawsuits also account for quite a bit of the differences in listed powder charge weights.

I have done extensive load testing with the 39 Sierra BK using both Hornady and WW brass, Remington 7½ primers, and various loads of H4895. I now use WW brass for all my 39 gr. Sierra loads. I have over 2,700 rounds down the barrel of my Savage 12VLP in .204 Ruger and it still likes 28.0 grains of H4895 and the 39 gr. SBK. There have never been any signs of excessive pressure with this load and I have shot it on days when the temperature has been well over 100º above. Here are some scans of the best 100 yard groups shot with that load:







As you have stated, you will have to work up your loads for your particular rifle, but the companies that publish the load data don't want anyone suing them because a reloader's rifle blew up with a load they listed as under the max. I believe most of the companies tend to list loads on the conservative side and that may well be the main reason Hodgdon/Hornady and Sierra load data vary so much between the 40 gr. V-Max and the 39 gr. Sierra BK.

[GaCop103]

Man! 53 degrees in August! You should be in Georgia, temps are high 90s with humidity to match. Georgia's like a flash back to Vietnam.............we even have the red clay.

[Melvin Eades]

leojlafrog,

I also load 28.0 grains of H4895 behind the 39 gr. SBK using WW brass and Rem. 7 1/5 primers. I haven't seen any signs of pressure in my rifles but yours my be different. I did a little experiment back in Sept. 2008 to see how my rifles shot this load and was surprised how well they did with it. Here is the link to that experiment.

http://www.204ruger.com/forum/viewtopic.php?f=4&t=5551

If you try this load, work up to it gradually, your rifle may not like it or it may not be your most accurate load.

[Aussiedogger]

I've tried looking for correct data on reloading my 204 with H4895 and 39gr Blitzkings. I've noticed on the Pet/favorite loads that many people are running 27.7gr which is max for the 40gr vmax. Looking up sierra's info, they recommend a max of 26.5gr? A full 1.2gr powder difference for a bullet that weighs 1gr less seems excessive to me. Now obviously I'll have to work up my load and see what works but I'm just curious as to why such a large difference in recommendations between the two bullets. Any info would be greatly appreciated.

Thanks, Joel

Joel, there are a lot of variables when it comes to any cartridge/powder combination. The variables start with the metallurgy of the projectile. Different temper/hardness of the copper jacket between different manufacturers might be kept to a minimum but it is all part of the equation. Just as the slight differences in powder lots factors in. Add into the equation the differences in chambers even among the same rifle from the same manufacturer because the chamber reamers wear with use and are always made to allow an amount of sharpening during the life of the reamer. So when it comes to published reloading it is not uncommon to find differences. They have to look at what would be called "worst case scenario" and provide data that would be safe in that case. Plus when they do the compilation of data the variations in the other factors come into play.

[Rick in Oregon]

Aussie: You do realize that this thread is 9 years old, right? Chances are the OP is long gone and solved his perceived problem by now. But thanks for the input nonetheless, one never knows......