How To Achieve More Shots From A SIG Virtus

This post about how to achieve more shots from a SIG Virtus PCP air rifle appeared as the result of a question to the HAM offices. I suggested a larger capacity HPA regulated tank could work.

Also I contacted SIG’s Airgun Product Manager, Rodd Rambo, for his suggestions. His comprehensive reply forms the basis of the information below. Thanks Rodd!

As Steve indicated, the main thing you’ll need to be aware of when upgrading the HPA tank/bottle for the SIG Virtus is that the tank’s output pressure remains in the same range. The actual size/capacity of the tank doesn’t really matter other than just form factor.

More Shots From A SIG Virtus

The tank which the Virtus uses is the same design used by paintball guns and technically any paintball tank could be attached to the rifle since they all use the same thread and valve mechanism.

However, the tanks used by paintball guns are equipped with different regulators which typically producing around 800 – 850 PSI. The Virtus uses a regulated pressure of 1,100 PSI.

More Shots From A SIG Virtus

If you used a tank with a lower output regulator it would result in reduced velocity. It could cause the rifle to not cycle properly due to the springs being set up for a higher pressure.

So, while there are a lot of options out there when looking through paintball tanks, you have to be mindful that most “standard” paintball tanks do not produce enough pressure unless you were to replace the original regulator with a higher output regulator. That can get rather pricy and can be a little complicated if you are not used to working with HPA tanks.

More Shots From A SIG Virtus

However, to achieve more shots from a SIG Virtus PCP air rifle, there is a solution I can recommend…

The original tank has a 13 cubic inch capacity and fills to 3,000 PSI. It is constructed from aluminum. Aluminum tanks are relatively inexpensive but can only hold up to 3,000 PSI fill pressure.

Carbon fiber tanks (these are are technically aluminum tanks wrapped in carbon fiber) can be filled up to 4,500 PSI. These are more pricy and typically only come in the larger sizes used on paintball guns.

Because of their size, carbon fiber tanks would not work very well with the SIG Virtus. It would be like screwing something the size of a nerf football into the back of the rifle!

However, there is a company called First Strike which produces a 13 cubic inch, 4500 PSI carbon fiber tank. This is the same physical size as the original but has 1/3 more air capacity due to being able to be filled up to 4,500 PSI.

More Shots From A SIG Virtus

First Strike also has similar 15 and 17 cubic Inch HPA tanks. These are all 2-Inch diameter tanks. This is the same diameter as the original Virtus tank and just vary in length. That will affect your LOP if you go to a larger cubic inch tank.

These First Strike tanks can be ordered with a 1,100 PSI output regulator. Just what’s required for the Virtus!

The only thing I am not sure of is if the original buttstock cap will fit correctly onto these tanks…

Although they have the same 2-Inch diameter, the original tank has a flat bottom while the carbon fiber tanks have a rounded bottom which could affect how the cap fits on.

If that becomes an issue, there are companies that make aftermarket buttstocks which would most likely work. I’ve unfortunately never had one of these tanks in-hand so I can’t confirm compatibility with the Virtus’ factory buttstock cap.

Here’s a link to the 13 cubic Inch tank. The regulator you would need to select from the drop-down menu is the Ninja Pro V2 SHP. (Super High Pressure = 1,100 PSI)

More Shots From A SIG Virtus—half-pint-13/4500—choose-your-regulator-/

Rodd, thanks for the great information about how to achieve more shots from a SIG Virtus PCP air rifle!

I can add a little more information about an alternative buttstocks. I have used a First Strike Universal Floating Stock with the SIG Virtus and it looks great – as you can see from photographs in this story. Here’s a close look.

You can find them here