Larry:
Yes, there is a variation in published Hornady Light Magnum ammunition against the velocity load data that is listed in the new 6th edition "HORNADY HANDBOOK OF CARTRIDGE RELOADING" Volume I of the 2 volume set. The reason is the the 7mm-08 Rem Light Magnum ammunition is the only ammunition that we load for the 7mm-08 Rem. cartridge. The powders that we use in the Hornady Light and Heavy Magnum ammunition is NOT available for over the counter sales to reloaders. The powders are designed as "C" (Commercial) powders only and we had the powders developed for the Light & Heavy Magnum ammunition. The Hornady Custom ammunition is standard ammunition that can be duplicated for velocity by handloading (of which we do not load the 7mm-08 Rem. cartridge). I shoot a 7x57mm Mauser cartridge and I can not reload to the velocities of the Hornady Light Magnum 7x57mm Mauser ammunition. The same goes for the .308 Win. ammunition that we load in the Light Magnum series of ammunition. You can duplicate the Hornady Custom series of ammunition from our reloading manual, but, will be unable to with the Light Magnum velocities. The Hornady Light Magnum and Heavy Magnum ammunition is kept within S.A.A.M.I. pressure specifications. You will note that all the Hornady Light Magnum and Heavy Magnum ammunition is loaded to a much higher velocity than what a person can handload out of our reloading manual and that is due to the types of powders being used to obtain the higher Light & Heavy Mag. velocities and still keep within S.A.A.M.I. pressure specs.
You will find that the load data in other reloading manuals such as Nosler and others can not duplicate the velocities that we can achieve with our factory Light & Heavy Magnum ammunition and still be within safe S.A.A.M.I. pressure specs.
The only way for you to obtain that extra velocity out of your firearms and that is to shoot the Hornady factory loaded Light Magnum ammunition.
The best to you in reloading, shooting, & hunting!
Lonnie Hummel
Thought some of you might be interested in the response I received from Hornady. Seems straight forward and honest.
long
