Winchester load for 7mm Rem Mag?

[Jimfern]

I am trying to duplicate the Winchester 150 gr Power Point Plus factory load for my Ruger M77. I have WW brass, primers and 150 PP bullets and tonight I pulled a factory load and measured 73.6 gr.s of powder. I assumed it would be Winchester 760, but the grains look larger and the load is much more than any of my manuals show for 760.

Does anyone know what powder Winchester uses? Thank you for any help you can provide.

 

[NCsmitty]

Chances are, the factory powder is a proprietary powder that you can't duplicate. Hodgdon lists a Max load of 60.2gr for Win 760 under 140gr bullet and nothing for 150's. So it sure is not Win 760. It's closer in grains to Retumbo with a 150gr bullet. (72.5gr Max) So it's probably a real slow burning powder that you won't duplicate exactly. Look at www.hodgdon.com for some data.

NCsmitty

 

[Jimfern]

link

Thanks for the link. I did notice that the amount of powder they used nearly filled the case, so I'll try some powder that does that while staying within the max load. I have some 870, Vit 165, 4831 and the 760 to work with. I have seen burn rate charts all over the web, but has anyone seen a bulk chart? I'd like to know which powders are the bulkiest.

During lunch I noticed that the 870 offered the most grains for the maximum load so I opened it up and it looks very similar to the factory powder that the Winchester load has. The only real difference is that the 870 seems to have a shine to it versus the Winchester stuff that seems dull.