Weird jam

[svandamme]

I've had this a 2-3 times now.
It seems to happen with reloads 230 grain ball , 6.6 grain VV N340.
As i'm shooting, round fires, nothing noticibly different, a new round chambers, but the slide does not go completely go forward.
Can't put on the manual safety because the slide is not forward as i should.
the hammer is fully cocked, trigger won't budge because slide is not forward.

But the barrel/slide seems locked, there is no gap between rear of barrel and slide.






The really weird thing, is that the slide is then very, very tight, i can hardly rack it to eject the round. It takes quite some force to cycle it again.

And if i then load some factory ammo after the failure and let the slide close with the slide release. Or i rack the slide, the new round chambers, but i get the exact same issue. Only when i rack the slide a few times empty does it go away.

I've since stripped the gun completely, could not find anything wrong , can't find any odd wear or marks.. It's just a weird occurance..
Now i could accept something in my loads was wrong, but i have a hard time understanding how this failure happens and as such what would be wrong with the load.
Did not feel like a hot load, and did not feel weaker. Even if it was weaker, how would it cause this jam?