First and foremost, let me preface this with, "you will be hard pressed to find a bigger proponent of Blackhorn 209, than me"! But let us not go walking through the fall/winter woods with blinders on. Some obviously have a lucky horseshoe, rabbits foot (remember those?), or are holding their mouth just right. Not all will be so lucky!
That Triumph plug is more than what I call etched, that is pitted. It does show you that those interrupted thread breech plugs with gas rings do not even come close to sealing.
The Accura plug is also pitted, to a lesser degree. It's design seals much better.
What I consider etched, is not red rust, it just makes the stainless surface a bit chalky looking. No brownish red pits, just a white frosted look.
Thanks for your confession. I'm sure there are lots more out there, but several will never admit it. Some will choose to ignore it. I will have to see if I can find a couple of those test plugs that were also pitted after just 3 days.
We discovered this way back, 10-11 years ago while testing rifles of all makes and platforms.
Believe it or not, #11 caps will ignite Blackhorn 209 in certain platforms. Albeit, not without slight delayed or hangfires.
We also discovered that the hotter 209 primers provide a much more complete burn of the powder. The marginal ignition types and lesser 209 primers were WAY more apt to give an incomplete burn in the barrel, and we're much more conducive to accelerated corrosion. That's why I always (and Western too) recommend using the hottest 209 or LRMP primers that work for your rifles.
If you recall, the first lot of Blackhorn was released to the public in early April, 2008. I bought the first case shipped to Michigan, and it was Lot #4, bottled on 4-3-2008.
The containers had "Noncorrosive - easy cleanup" on the front and did through at least lot #8. However they added an asterisk (*) to it after the first label change to "Noncorrosive* - easy cleanup". They also added a disclaimer that "* Blackhorn 209 IS NOT a bore protectant".
Somewhere between Lot #8 and Lot #12 they changed the wording to "Extremely low residue - easy cleanup" and dropped the "noncorrosive(*) wording from the label completely. They also added a blue "WARNING" disclaimer on the back label.
Here are all three of these earlier labels side by side. Three sides of the label, as the other side panel was unchanged over this period. You might have to zoom in to read them?
I know some don't agree with me, and that is OK, as long as you can afford to let your rifle possibly get corroded. Some spend a couple thousand oo more dollars on a rifle, some work hard to afford and entry level rifle. I don't want to see anyone let their rifle get pitted, trying to hunt on a fouled bore, or going too long without cleaning. That time period will be different for every rifle, geographical location, humidity level, weather conditions. However, I KNOW it can possibly go 3 weeks with one rifle and breech plug during hunting season, and I ALSO KNOW things can go south as fast as 3 days with other rifles and breech plugs.
It's your rifle. You paid yer money, and you takes yer chances!
I still think Blackhorn 209 is the best black powder substitute ever made, and I've tried/tested them all.