Right out of the box, w/ external adjustments only, we managed an impressive shot string;

(180 BAR regulator setting, Maximum hammer spring tension, power setting set to 'HIGH')
using JSB EXACT JUMBO HEAVY 18.13 gr;

1022.1
1022.1
1036.6
1027.7
1029.3
1032.5

which translates roughly to 58 Joules of muzzle energy about.

NEW AIR VENTURI AVENGE-X

Your Airgun. Your Way.

With this system, your customer can buy ONE air rifle now for $500 that can be adapted with interchangeable calibers, air supply and stocks! Buy now, upgrade later.

Air Venturi AVENGE-X (X1-BT)

The Avenge-X platform features an externally adjustable regulator, hammer spring AND transfer port to allow for even more tuning possibilities than our entry level Avenger. Whether you are looking to shoot all day off of a single fill, or want to send your projectiles downrange at blazing speeds and energies, the Avenge-X is built to do it all. Even if the modularity doesn’t excite you, the tunability, quality and overall performance of these rifles is sure to get your attention.

Change the style, caliber and air source as needed, in just minutes!

– Need a classically styled .177 for target shooting and small pests? Done.
– Need a bullpup in .22 to go after squirrels in the woods with? Done.
– Need a tactical .25 to shoot longer distances from the bench? Done.

Features:

All aluminium receiver, featuring a split row of Picatinny (MIL SPEC 1913) rails on top.
There is a lengthy rail section under the bottle as well, to chuck your bipod onto or otherwise, whatever other accessories you'd prefer.
The cocking lever and its arm is all-metal. This cocking arm actuates in a far more refined manner than the one on the LEVIATHAN.. The finesse here is reminescent of the REXIMEX THRONE.
The safety switch is still the old pendelum time, but toggles here more crisp and positively
The buffer tube is aluminium and by no means is like a cheapie paintball marker stock - this one is precise and the telescoping buttstock actuates very crisp, locking in the different respective positions. He also do like the firm rubber tekkie feel on the back of the stock. There is a socket point on the rear of the stock, just above the toe, whereas the stock itself features a sling loop for thronging a sling through. As you may have guessed - COMM-SPEC telescoping buttstocks will fit on here.
The guages are positively marked for their designated measuring purposes too - fill pressure, and regulator, respectively. Their dials are colour coded red and blue for emphasis.
HIGH / LOW power setting adjustment., Presumably, this adjusts the diameter of the transfer port
Available in .177 .22 .25 interchangeable calibers
The rifle stock itself features a hole through which one can insert the included filling probe to fill, alternatively, one can use the male Q/C fitting (w/ the brass filter) on the bottle itself
Cocking lever reversible for left hand shooters. Installed RH by default
Shrouded barrel with ½ x 20" UNF bushing at muzzle for threading on an air rifle silencer
500cc Aluminium bottle - 250 BAR FILL PRESSURE. NB. Please note that you can remove the bottle with or without pressure in, meaning the bottle self-contains its fill pressure.
Regulated - externally adjustable w/ a stainless steel flat-drive screw, similar to the LEVIATHAN
Hammer spring externally adjustable - Use the included 2.5mm allen key. Threading the screw inward (clockwise) increases the tension on the hammer spring, increasing muzzle velocity. Threading the screw out (counter-clockwise) accomplishes the opposite.
Trigger is fully 3-point adjustable;

Trigger Sear Screw: This screw engages the lower sear as the trigger is pulled. Turning this screw clockwise will reduce the amount of engagement required to fire the rifle (making the trigger more sensitive). Turning this screw counter clockwise will increase the amount of engagement required to fire the rifle. DO NOT make large adjustments to this screw. Adjust in small increments and test for proper function before adjusting further. 5)
Trigger Weight Adjuster: Turn the adjuster screw clockwise to increase trigger pull weight, and counter-clockwise to decrease trigger pull weight.
Travel Adjuster: Turn the adjuster screw clockwise to reduce the amount of trigger travel (take up), this will visibly move the trigger towards the rear of the trigger guard. Turning the screw counter-clockwise will increase the amount of travel (take up) and visibly move the trigger forward within the trigger guard.

There is a degass screw on the left face of the rifle.
The telescoping stock is 6 point adjustable and the length of pull can be adjusted from 11.25” to 14.5”

MAINTENANCE

Apply silicone lubricant to the breech o-rings on the bolt probe every 3 months or every 500 shots.
Apply a thin layer of Moly paste to the bolt probe every 3 months.
Always store with pressure (at least 1,000 PSI/69 BAR) in the air rifle. Store in a place that is dark. Keep out of high humidity.
Inspect the barrel o-rings any time you have the barrel out of the action. Apply silicone lubricant to these o-rings before inserting the barrel into the action
Periodically check that the two slotted screw

Included in the box, you will receive;

1x 10 shot standard capacity magazine, .22 cal
16x high capacity magazine, .22 cal
1x Single shot loader, .22 cal
1x Stainless steel filling probe
1x bag of allen keys, nickel plated
1x bag of assorted O-rings. Looks like a set of 2x rebuild kits
1x English Instruction manual
No optics / iron sights included

Please have a look here;

Also here;

The warranty shall be invalid if the Airgun:

• Has been incorrectly disassembled, reassembled or maintained.
• Has been fitted with non-Air Venturi parts.
• Has been abused, misused or improperly stored.
• Original purchase receipt cannot be presented.