Looks like a nice piece.
The user manual is here and has an explanation how to work on jams, etc. Google is your frenemy.
https://www.evanix.shop/products/viper
I don't have a Viper, but for my Marauder Pistol the number of pumps is kinda like how many licks to the center of a Tootsie Pop. (Owl ~= tank)
https://www.youtube.com/watch?v=O6rHeD5x2tI
The number of pumps from a Hill hand pump for the Marauder from empty to full is several sets of 20 to full. (Alex, I'd like to buy a preposition?) Whether that's 60, 80, 100..., don't remember. Plus side, it's one of the few things I can do and not be as worn out as some skinny runner health nut.
Behold the Power of Beer!!
Attached FileThe accuracy starts to go (PoI shift) as the pressure gets 'low', so you won't be refilling from '0'. Depending on your pump, how much you shoot the pressure down, etc, refilling could take 20, could take...
So far, when I've been at the range people have wondered WTF I was shooting. With the shoulder stock, barrel shroud, and air rifle scope, it looks kinda bad azz. Then it's phft, phft, phft and holding a group of 0.22" holes inside a 1/4" at 25 yards, people ask about it and don't turn down a chance to try it. But, they gotta pump it up first!
I keep it at least partially filled during storage. Supposedly PCP seals like being filled better than being empty. Also, doesn't require as much beer power to make ready...
Yes, I dropped a box of emoji's and had to put them somewhere.
Hope some of it helps and wasn't total nonsense.
PN