One of the most important questions in this discussion should be... "Is the ignition reliable"?
If the breech plug and modules containing a LR Magnum primer reliably ignite the powder charge every time, then you do not need the extra firepower of a 209 primer.
I once had a customer bring me a breech plug and primer modules similar to that used in the Remington 700 UML, and he wanted me to use these components to build him a smokeless muzzleloader.
I could get the system to ignite the smokeless powder some of the time, but not all the time.
Nobody wants a "hang-fire" or a "burp" when that buck of a lifetime is standing 100 yards in front of you.
This happened before I got the LRMP type breech plugs and modules made by Hankins, and Arrowhead.
The LRMP modules act like a funnel to direct the heat and pressure from the module into the breech plug.
The Remington 700 UML system basically has the funnel upside down. Turn a funnel upside down and try to pour something into a container through the narrow end and see what happens. How much of the heat and pressure is wasted in the UML design, if the headspace is not perfect?
Yes, I know it works with Black Powder, and the substitutes, but it is not the ideal system for smokeless.
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