Thread: WLRM by mistake
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Old 01-01-2010, 01:55 AM
ma96782 ma96782 is offline
Join Date: Oct 2009
Location: Vancouver, WA
Posts: 209

For liability sake.......use what your reloading manual says to use.

Then..........there are times when a magnum primer is used because it's needed............


Magnum Primers

Magnum primers contain a greater amount and/or slightly different explosive mix than is used in standard primers. On ignition, magnum primers give longer burning, hotter flames. Their use is recommended for (1) any ammunition that will be used at or below zero degrees F., (2) with most Ball powders and (3) with slow burning rifle powders like MRP and IMR 4831 in very large cases. Magnum pistol primers often will give more uniform velocities in magnum handgun cartridges loaded with large charges or slow powders like 296, 2400 and H-110. Magnum primers may be used with faster burning or easy-to-ignite powders, but normally there will be no advantage in doing so. As when changing other components, it is advisable to reduce powder charge weights on initial loading with magnum primers.
Know that subsitution of components comes with some RISK. Before proceeding, evaluate what your own risk tolerance level is.



How do changing various components affect chamber pressure and velocity?

And, that is only changing brands.
Then again.........for liability reasons, I'll add..............


Never mix or substitute components.
Every lot of powder, primers, bullets, brass, and any other components can differ significantly. Different manufacturer's components differ substantially. For example, never substitute Federal brand primers for Magtech, and expect the same results. One primer may be fine with your load, but another brand may cause extreme pressures with the same load. Don't substitute magnum primers for standard primers for the same reason. Just because two brands of powder have similar characteristics, that does not mean they are interchangeable or mixable. Every time you finish with a lot of a component, you will have to back off the load slightly and start over, checking for overpressure signs, just as you did when you first worked the load up. You are in essence working up a brand new load.
Taken from the Magtech web site.

Aloha, Mark


Last edited by ma96782; 01-01-2010 at 02:03 AM.
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