Baby Luger Breech Block Slap

[milesc2]

I was inspecting my baby Luger after my first range trip with it and discovered that the breech block had been hitting the inside rear of the frame.

The damage was minimal and I was able to clean it up pretty well with some light sanding.

To try to resolve this issue I installed a longer mainspring. I believe it now has the longest possible mainspring installed. (any more and the action would not cycle enough to engage the hold open)

It seems the issue is MUCH better now but after firing about 130 rounds I can see a small amount of breech impact on the left side of the frame. It is very slight compared to before but I don't think these surfaces should be touching at all.
I dismantled the pistol several times while shooting and it appears the mark was not getting worse it was there after the first couple mags and stayed the same as far as I could tell.

I am using regular Winchester white box 9mm Luger 115 grain.
I see no galling, wear or damage on another part of the pistol.
The gun passes the tape test just fine.

My questions:
Is this amount of impact normal? Will it cause issues down the road?
Why would the left side be the only one getting hit?
If need be what can be done to correct the issue?

First photo shows the frame after I cleaned up the original damage.

Second photo shows the frame after 130 or so rounds fired.