Crash on Surface Tension

I always get a CTD when firing the RPG at the chopper. In my event logs it reads:

Faulting application name: hl2.exe, version: 0.0.0.0, time stamp: 0x470c11ae
Faulting module name: client.dll, version: 0.0.0.0, time stamp: 0x504ecc4f
Exception code: 0xc0000005
Fault offset: 0x00362edd
Faulting process id: 0xcf8
Faulting application start time: 0x01cd940d22dd7064
Faulting application path: c:\steam\steamapps\lister8\source sdk base 2007\hl2.exe
Faulting module path: c:\steam\steamapps\sourcemods\bms\bin\client.dll
Report Id: 114eda50-0001-11e2-baff-f46d04af08c0

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