I just noticed something with my HK P30s 9mm dry fire, after I pull trigger the hammer drops, the hammer kinda bounces back a little and stays not fully forward but about 1/8" back? I can use finger to push hammer forward (feel some friction) to fully seat, then I can pull hammer back 1/8" but now it won't stay but goes back to fully forward by itself under some spring force. So this hammer "stays back 1/8"" only happens after dry fire and hammer drops and bounces.

It shoots fine with maybe a hundred rounds, I don't know what's causing this?
if you own P30, does yours do the same thing?

If there's nothing wrong why worry about it???

You'll need an HK armorer to explain the workings to you but this is the firing mechanism and is normal.  I know the two springs and plunger that are doing this, but I have no clue what their names are but they are part of the firing pin safety (the only way I can describe it).

I don't have a P30 but the USPs all do this and I would presume the P30 is similar.  The hammer does not rest on the firing pin when at hammer down, it only contacts the firing pin from inertia when dropping from full cocked.  The trigger does have to be pulled in order for the mechanism to allow the hammer to go all the way forward to the firing pin.  Part of the safety systems.

This.  Very similar to Colts series 80 trigger system.  Pulling the trigger completely to the rear actuates a lever that pushes up on the safety plunger that frees the firing pin to move completely.  The hammer has a safety half notch to prevent falls on the hammer to discharge the gun.  Hammer drop safety.

Sig's do this also.  Basic physics at work Netwons 3rd law.... Every actions has an equal and opposite reaction.  When the hammer hits the FP the spring on the FP is compressed so it recoils backwards after the hammer transfers the energy.  You normally do not notice this because a slide is coming back after you fire.

thanks everyone for the replies

it seems the 1/8" gap is not tied to any safety mechanism, otherwise the gun is not safe, since as I said I can push it to fully forward, or leave it 1/8" open, both cases should work the same with firing pin block engaged. please let me know if this is not the case then I need to send my p30 in for HK to check

I disassembled the gun to look at the hammer area carefully, it seems the hammer can move 1/8" freely, sometimes held in position by friction, sometimes will move by spring, depends on the trigger position, but I don't see any important mechanism linked to it...?

don't know what the benefit is for that? with firing pin block engaged, the firing pin can still go forward to flush with the housing, in other words, the hammer can rest on firing pin (or even push it forward a bit) without the risk of AD when dropped

Well I don't know about the HKs, but SIG uses a "safety intercept notch" as an extra added layer of drop safety. The hammer will be a bit off the firing pin, and cannot be pushed forward. So if the pistol is dropped and the firing pin block either is faulty or happens to bounce out of the way, the hammer still shouldn't strike the firing pin.

I don't think HK uses such a notch, but I only have a P7 and VP9; no hammer fired HKs.