BH ignites reliably in sub-zero weather.
Breech plug design is critical. The past 2 winters have seen me testing, testing, testing, and retesting BH in sub-zero cold. So many times my rifles were left loaded, uncleaned in the truck overnight in sub-zero weather. With the proper breech plug, i never experienced a delay, or a misfire. Normal shot gun primers are what was used.
What i found is the Omega plug is 100% reliable. Modified CVA plugs are 100% reliable, but OEM CVA plugs will experience delay, and misfire.
The plug in the Triumph is 99% reliable, but ever so seldom i had a delay. I believe the plug in the pro hunter is very similar to the Triumph plug, and as such should be very very reliable in sub-zero weather for igniting BH. I could make it 100% reliable, but now is not the time.
Don't buy into the malarky that you need to enlarge the flash hole and/or flash channel to improve ignition of BH. Nor do you need to use magnum primer.
My opinions are just that opinions, but they are based on burning a case or more of BH209 in sub-zero weather, not on what i have read.
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