Merc High Velocity Rounds not working with Splinter t2 support gem

I attempted to utilize the break armour on Splinter with the High Velocity Rounds skill to make the skill break armour on its own without the use of armour piercing rounds.
I was able to apply the gem to the skill, but it does not apply armour break to any enemy that I hit. ( No Armour Break counter underneath enemy health bar)
I have tried this with other gems and just by itself, none apply the armour break even though it does show the 15% armour break from physical damage when looking at the damage tab of high velocity rounds.

I also can't get this to work with High Velocity but it works for every other crossbow skill I've tried so far. Hope they fix this soon!

Same for me

Same here

Same here, no form of armor breaking works with that skill, tried with support gems aswell as Shattering Blow tree notable

Hey guys I found out what's going on, High Velocity is a payoff tagged skill which means it can't cause armor break since armor break is what causes it to "payoff". If you hover over the tag in game it explains that. So regardless of what happens you can't cause it to shred armor. There's a possibility you can use another skill to poison an enemy and then give that skill that one corrosive support so it can break armor. But that does mean you have to reapply the poison and the break is based on the poison damage so might have to scale that as well. Really feel like this skill isn't very good since it can't cause armor break but maybe end game it gets better.