It isn't Makarov ammo, is it? Just thought I'd ask the obvious...9mm reloads? Could be a burr on the feed ramp? Noticed the slide is not properly aligned with the polymer on both sides of the gun? If not, slide wasn't aligned properly when reassembled. Just trying to cover all the bases here.
If it isn't, and you don't have any success with how far your experience takes you, and want to take it to a smith, call him first. Don't take it in before you call.
Treat that muzzle like a ticking time bomb and keep it pointed in a safe direction until you fix it, as noted before.