Summar on Leica M6

[Gilo25]

Is it safe to push in a collapsible Summar mounted on a Leica M6 without damaging the curtain? It looks to me that it doesn't touch but it seems very close. Or is it just my impression?
Thank you all!

 

[photobizzz]

If you open the back and put the shutter on B you can mount it and see...I dont think it will hit though.