Air Venturi Avenger X effectively unregulated

drdirk said:

After less than an hour the regulator and tank pressure are the same.

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This behavior is generally caused by degradation of the regulator O-rings. They progressively harden and eventually fail to seal properly, and the reservoir air slowly migrates through directly to the plenum.

Perhaps worth noting that although it is a form of pressure creep, it is different from what is generally referred to as "regulator creep" which is something chiefly caused by surface imperfections in the valve seat.

If you're interested, there are a few links in my profile dealing with regulator issues and how to address them.

There's more than a few fine shooting, quality unregulated airguns appreciated by owners for simplicity and reliability. My decision to go with a regulator is based on understanding the ammo I'm using prefers a certain amount of air pressure for consistent accuracy. Unregulated air, direct from reservoir, will start high and fade away, just like releasing air from a balloon, the ammo-preferred pressure coming mid-range. A regulator, while not providing a higher shot count, will release a set amount of air per shot for more consistent accuracy start to finish. WM

If all you shoot is 30 yards it really won’t make a huge difference as you are already seeing. It would bug me though and I would have to address it. I would drain the gun of air and turn the reg way down. Then fill it back up and ease the reg back up to about 1900-2000 in 22 and about 2100-2200 in 25 and see what happens. You never know maybe just adjusting the regulator will break something loose and it might work better . If that doesn’t work I’d just replace it. I remember at one time seeing them on eBay. Probably be faster than dealing with AV or PA that seems always out of stock on such things.

Yesterday, in "General Discussion," Boomer1974 started a thread, "Avenge-X Replacement Parts." A link was recently posted to Pyramyd Air's Avenge-X section that might help securing another regulator. Best of Luck, WM

Or a 2 second search on eBay

Pressure creep is caused by surface imperfections in the regulator's valve seat (wear, or damage, or machining marks). Many times it can be fixed by fine wet sanding. Again, there are links in my profile that go into with more depth.

I have an Avenger but rarely shoot it because it is so LONG. I have not taken the regulator out of it. But I've rebuilt 3 SPA regulators within the last week and also a Huma a year or so ago. I tried just reapplying silicone grease (not oil) to the O-rings on the last two and it did not fix them. It did work on the Huma which was new. The SPA I did yesterday was mine from when it was new and was 3 years old. I replaced all the O-rings carefully applying silicone grease to the O rings in a thin film. Works great now. I don't know how old the other two were but after O-ring replacement they also are working well.

So rather than replace the regulator I would at least try O-ring replacement. You will need the right size O-rings, a little silicone grease, and some snap ring pliers. Nothing expensive. If somebody does not help you with the size of the O-rings you will have to take it apart, remove them, and measure. The stem you adjust the regulator with has a small O-ring or two, the stem below it with the spring washers on it will have one or two. And a bigger one at the bottom. There are O-rings on the outside too but I do not usually replace those. Just apply a little new silicone grease. So if your regulator is like the ones I've worked on you probably need two sizes of O-rings. I pull out the adjustment stem, remove the snap ring, then push or pull out the piece with the bellville washers and the hard plastic seat on the top. Be careful to not drop all the washers at least until you know how they are arranged. A picture is a good idea. Under the adjustment stem is the hard plastic seat of the regulator. You do not want to push on it with something hard and pointy. A wooden dowel would be great.

You could also remove the regulator, regrease the O-rings after measuring them and try reassembly. If it still doesn't work you now have the size of the O-rings and can order them. If it does, I still would order new O-rings unless the gun is very new.

To use an unregulated gun you need to shoot a shot string from full fill pressure (or at least a high pressure) to the point you get an unacceptably low velocity. Write down the pressure periodically, like every 5 or 10 shots. Pick the velocities you like and use the gun in that pressure range. It would at least allow you to keep shooting while waiting on a regulator or new O-rings.