To the OP, I have shot thousands of rounds of Wolf of both lacquered and polymer. I've have had only a few stuck cases. On my 6920s, I've gone over 3K rounds between cleanings with no stuck cases. On my LMT, I get them every 800 to 1000 rounds fired or so, with the tar or carbon/oil mix residue you mentioned. On my Sabre upper/Colt lower, zero stuck cases with over 5K rounds on the gun, cleaning every 2K or so. That tells me the LMT is a little more finicky and the chamber and bolt lugs needs to be cleaned more than the other 3. I've also had a few stuck cases when mixing Wolf with brass Prvi ammo on the same range trip and so have other folks on the range. It's odd that I intentionally tried to get a stuck case by mixing steel and brass in the same mags, a few years ago and couldn't do it.
So now, I don't mix the ammo.
As far as velocity, what is considered the definition of underpowered? I realize this is not match ammo in any stretch of the imagination, but is 9, 50, or 100 fps slower than M193, considered "Way" or "Very" underpowered?
M193 55 gr FMJ 3250 fps
Wolf BB 55 gr FMJ 3150 fps
Wolf MC 55 gr HP 3241 fps
Wolf MC 55 gr FMJ 3200 fps
Wolf BB 62 gr FMJ 3052 fps
For God and the soldier we adore, In time of danger, not before! The danger passed, and all things righted, God is forgotten and the soldier slighted." - Rudyard Kipling
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