Air Venturi Avenge-X with Custom Barrel

[caliusoptimus]

Picked up this avenge x a while ago... awesome rifle for the price but it has some things that bother me so... on to the mods!

The overall length of the bullpup avengex is pretty short... on top of that several inches of the stock barrel is the moderator. It was begging for some more barrel length so I picked up a (.25, 1:22", 28.5" long) TJ liner and machined it to fit. Over the liner I went with a carbon fiber tube to tension the barrel.

I found an issue with this design shortly after getting it.... the action is only held to the stock with a single screw. The other end is held on by a barrel clamp piece that supports the gun from the barrel, with the bottle left floating. Not a big fan of supporting any weight with the barrel for obvious reasons... so that had to change.

I modified a CRC precision bottle clamp (billet aluminum) to replace the original clamp and hold the bottle tight. Now the stock is attached to the clamp, the clamp is attached to the bottle, and the barrel is floating free!

Excited to put this through it's paces.

 

[Ranchibi]

Awesome mods! TJ makes incredibly accurate barrels/liners!

 

[Freddy J]

What caliber and twist do you have?

 

[Scotty1]

What caliber and twist do you have?

(.25, 1:22", 28.5" long) TJ liner

 

[124nut]

Picked up this avenge x a while ago... awesome rifle for the price but it has some things that bother me so... on to the mods!

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The overall length of the bullpup avengex is pretty short... on top of that several inches of the stock barrel is the moderator. It was begging for some more barrel length so I picked up a (.25, 1:22", 28.5" long) TJ liner and machined it to fit. Over the liner I went with a carbon fiber tube to tension the barrel.

I found an issue with this design shortly after getting it.... the action is only held to the stock with a single screw. The other end is held on by a barrel clamp piece that supports the gun from the barrel, with the bottle left floating. Not a big fan of supporting any weight with the barrel for obvious reasons... so that had to change.

I modified a CRC precision bottle clamp (billet aluminum) to replace the original clamp and hold the bottle tight. Now the stock is attached to the clamp, the clamp is attached to the bottle, and the barrel is floating free!

Excited to put this through it's paces.

Nice bullpup. Loving mine!!!!!

 

[Freddy J]

What kind of groups are you getting? Also Pellet Brand and size.

 

[caliusoptimus]

What kind of groups are you getting? Also Pellet Brand and size.

Not sure yet. I've been playing with my rattler 357 for the last few weeks. This needs a few more things and when it's done I'll start tuning it up.

 

[jasperjet]

how did you chamber it? the factory barrel has a notch in it to line up the transfer port perfectly but you really dont need that , just a witness mark, looks really good. Except now I want one except I dont have a way to chamber it.

 

[caliusoptimus]

how did you chamber it? the factory barrel has a notch in it to line up the transfer port perfectly but you really dont need that , just a witness mark, looks really good. Except now I want one except I dont have a way to chamber it.

CNC lathe and a boring bar for the chamber/leade. Manual mill and a collet block for the port and the spot drills.

 

[caliusoptimus]

Had some time to play with the avengeX today.

Alien air guns made a new plenum extension for me. This made a pretty big difference, and I would recommend more plenum to anyone using a .25 avengex... if you want more power of course. It's awkwardly placed and doesn't fit in a case anymore... meh... maybe I'll find or make a plenum thay doesn't stick out so far. On this model (bottle bullpup) there is, unfortunately, nowhere else to put it.

Also got a lighter valve spring and heavier hammer spring installed. The heavier spring moves the adjustment range to the top end of the power range. It's about perfect with the reg at 210bar, and I'm sure it could handle more. Too much spring for running lower pressures though.

I spent an hour or two with the NSA 38.5gr slugs and got it down to 1moa-ish at 50yds. This was in the 900fps range (~70fpe). Some groups were half moa, some around 1.5moa. I think it can do better... but needs some work. Main thing I want to try is lapping the barrel... also want to get the velocity a little more consistent. I was also using the Tanto the whole time. Not sure if was helping or hurting accuracy.