It depends on the model. There are over 200 air rifles on the market. You can find anything from a Daisy Red Ryder for around $35 to a Feinwerkbau that will cost you over $3000.
It all depends on who made the air rifle and the power plant that the rifle uses.
it all depends on the condition of the rifle.
in general 180 $ is the minimum for a reliable rifle.
What condition is it in..
An Air Rifle is either a BB rifle or a pellet rifle. It uses air or gas to propel the projectile.
Don't put as much air in the rifle. If you have a dial to set the power then use it. As you shot the power drops. You can dry fire some PCP air rifles.
I am a little confused by your question. Do you mean Webley air rifle. I know that Wembly makes scopes but I am unaware that they make air rifles. If you mean Webley then I need to know the condition and the model of the rifle to give an estimate of value.
A sporter air rifle and what?
No
To get an estimate of value you will have to state the condition of the rifle and give the SN#. There are 5 different series of this rifle.
Are you asking how do you swap and air tank on an air rifle, or swap for and air rifle? In most air rifles you put it on safe and swap out the tank by unscrewing it and replacing it.
50-200 USD