Proton

Proton is an active expendable heavy-lift launch system. The commercial launches are operated by International Launch Services. Proton is now built only in 1 variant, Proton-M. There were also 2 other variants which are currently retired: Proton, Proton-K. The vehicle operates out of Launch Sites 200 and 81 at Baikonur. 

I recommend turning on "Advanced tweakables" in KSP settings.

To download each variant of Proton, go to the "Files" section.

Here are my other projects.

Proton-M, Proton-K

8S810K

8S811K

8S812

Proton-K
T-0:00:01 – Main Engine Ignition
T-0:00:00 – Lift Off
T+0:01:28 – Second Engine Ignition
T+0:01:30 – Main Engine Cut Off
T+0:01:31 – First Stage Separation
T+0:03:10 – Second Engine Cut Off
T+0:03:12 – Second Stage Separation
T+0:03:14 – Third Engine Ignition
T+0:03:22 – Fairing Deploy

Proton-M
T-0:00:01 – Main Engine Ignition
T-0:00:00 – Lift Off
T+0:01:10 – Second Engine Ignition
T+0:01:12 – Main Engine Cut Off
T+0:01:13 – First Stage Separation
T+0:02:52 – Second Engine Cut Off
T+0:02:54 – Second Stage Separation
T+0:02:56 – Third Engine Ignition
T+0:03:04 – Fairing Deploy

Calculated with full thrust.