Powder Data Confusion

[JRLSH]

Hello all, was doing some reloading and noticed a rather large discrepancy in two of my reloading manuals. My Lee manual is a 2003 edition and my Metallic Cartridge Reloading manual is a 1996 edition. Lee shows starting grains of 50.6 to max of 54.0 and my MCR book shows starting load of 55.0 gr with a max of 57.0 gr. This is shooting a 150 gr. jacketed bullet and I am using Lake City and Norma brass with Winchester 760 powder. So one manual shows a max of 54 gr and the other book shows the starting point one grain ABOVE the max the other book says. I would tend to go with the Lee manual as it is a few years newer than the other but is this a common thing in manuals? Will one show such tremendous differences from another and then, should you rely on the newest manual you have? What about the older books? How old is too old and throw away time?

 

[ScottRiqui]

What caliber are you reloading for? In the case of conflicting information, I'd go to the powder manufacturer's website. In this case, it would be the Hodgdon Data Center (they're the parent company for Winchester Powders).

 

[g.willikers]

That's why there's the emphasis on working up loads, and not just blindly trusting what is written in manuals.
They are guides and not always perfect.
Besides, the info might not even give the same results in different guns, or by different reloaders.

 

[Catfish]

If you are useing the same componates in the same tempitures you should get the same results as the book. But if you use heaver brass your presures will go up. As for primers there is no telling what is going to happen with a different brand. I once did a test several different primers in the same load. I tried several different powders and several different rounds in different calibers. With 1 round I had an extreem spread of 7 for 15 rounds useing 3 different brands of standard primers and 3 different mag. primers. With other loads there was quite a bite of difference. What really suprised me was that I did get 1 load that was showing signs of presure and that load was with a standard primer and none of the other primers in that load had a problem. All I know for sure is that different primers act differently with different powders and different loads.