I used 1 drop of SM50 directly into the transfer port of my old BSA air rifles (with leather piston seals) ever 100 or so pellets and never has any issues spanning over 25 years. This was on advise from Neroche Armoury my local RFD at the time. I guess in this scenario the silicone had no negative effects whatsoever, however not used on any other gun parts I would add.