It would not be a good choice as it is for firearms lubrication and has a low flash-point. Use a tiny smear of moly grease or SM50.
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I've used it in in dozens of rifles and it works great with plastic, rubber and leather seals. A £4.60 bottle will last for ages (years).
The PH stuff will cause dieselling and possibly damage the rifle. If you have bought some already it will be OK to lube the trigger mechanism and also as a light coating to inhibit rust on the OUTSIDE of the rifle. But don't put it in the compression chamber or deiselling will occur.