Tethered Bottle

[ztirffritz]

I have a small 90ci Carbon Fiber bottle. I have a Ninja PCP valve that is regulated to I think 2900psi ±10%. So it should be providing between 2610-3190psi. If I connect it to my gun on a bench and shoot will it effectively maintain that pressure so that the velocity remains constant until it runs out of air? Is there any reason not to do this? Will it damage the gun, tank, valve, etc in some way? Mine seems to fill the gun to about 2900psi no matter what the pressure is in the bottle.

 

[Guest]

You should be ok tethered.

 

[FearnLoading]

I shoot my guns tethered to the scuba tank. If the gun is regulated let's say at 150 bar and the max pressure in the gun is 250 bar, you can tether the airgun to the tank as long as the "scuba tank" is at 250 bar or less. Since the gun is regulated,the pressure on each shot is maintained at 150 bar. This way you can keep shooting till your scuba tank drops below 150 bar which is effectively thousands of shots. 

My scuba tank fills to about 300 bar. Once the pressure reaches 250 bar, I just tether it to the gun and continue shooting. This way I don't need to connect or disconnect after every 50 shots. This helps in effective utilization of air since I don't have to bleed the hose every time I refill. By cranking the knob of the tank open, I can shoot the full day. 

The only thing you should be careful about is that you should use a longer scuba hose. This way the gun has some movement while its tethered to the tank. A shorter hose will limit the amount you can move the gun around and you don't want a situation where you move the gun and it puts strain on the scuba hose. 

 

[ztirffritz]

My gun is not regulated. The valve on the tank is.

 

[Tominco]

Yes, no, yes. 
You're adding a regulator to your gun by tethering in this case. I have a similar setup as well as an adjustable regulator for my SCBA tank. I generally do not shoot with the bottle ON and gun tethered because almost all my rifles are regulated at this point. I just fill the rifle and then let the air in the line bleed out into the gun as I shoot. For you, you will in a way be adding 90ci to your rifles existing air reservoir and a regulator set to 2610-3190. 
The only reason I can see not to do this is if you have leaking air somewhere in your setup (until recently, that was the other reason I didn't shot with the bottle on). You'll have to address this first as it is a sign of something being not quite right and you'll lose a lot of air. Well... if you're going to let the bottle free hang off the rifle from the foster fitting, that would be another reason. But, I don't think you're planning on that!  
If your rifle is low when you hook up, just fill it slowly until it tops off then get to shooting. 
Happy Shooting!
Tom