I tried a Buna-N 70D O-ring for the gas tube end cap - it worked for a single charge, but the socker swelled up 25% - it's obviously not a suitable material. Now, I knew this from the get go, but I was surprised at how quickly it swelled and by how much.
Anyhow, just looking to find out what is the right size and material for these 2 O-rings that come in contact with the CO2. I used -113 size and that seems to fit well.
I've seen some recommend Viton and some Silicone? Can Viton serve for both or Silicone for both?