Umarex Komplete Cylinder Mod

[GerryR]

I took an expended Nitrogen cylinder and modified it to make it refillable using standard air.  A simple mod: drilled and tapped the end for 1/4npt screwed in a 1/4 to 18 npt adapter and welded it in.  I had a steel street tee and screwed that into the cylinder using Loctite 569.  I bought a miniature 0-5000 psi gauge from McM-Carr and a fill fitting (w/ checkvalve) from airtanksplus.  Right now I'm doing a leak-down test as, with great effort, I managed to hand-pump it up to 3600 psi.  The only thing I don't like about it is that I have to remove the fill fitting if I want to remove it and use the N2 cylinders, because it would hit the barrel otherwise.  The nitrogen cylinders come filled to 3600 psi, so I don't believe there are any safety issues.  All the fittings are good to 5000 psi plus.  Total cost ~ $45.00 less the expended N2 cylinder.  Should make plinking a little less costly.

[splitbeing]

Very interesting... the Komplete seems ripe for mods like this!

[GerryR]

The convenience of the N2 cylinders is nice, but at $24.00 for two, it can get costly very fast!  I hope this gives others ideas.

[Back_Roads]

 My only concern is how many fill cycles that "disposable" bottle can handle. With out knowing wall thickness and metal used in construction.

[eeler1]

Good point.  Appreciate the innovation.  But if the nitroair is designed for one use, it may not hold up well to repeated fills.  Maybe we'll find out, eh?

[Blowpipe Sam]

No need to pump it to 3600.  The OP said it was a chore.  2400 ought to be safe.

[GerryR]

I can easily get 20 shots at 3000 psi.  If the tank were to rupture, there is nothing inside it to launch, so besides scaring the heck out of me, I don't see what damage it can do.  Also, most of the tank is within the forestock.

[GerryR]

Just a small update: I loaded the tank to 3000 psi and was able to get 30 regulated shots from it.  The Komplete is regulated to 1800 psi.  I think that is pretty reasonable, and I have an extra 600 psi of margin from the 3600 psi N2 tank.

[lillysdad621]

is there a way to adjust the reg to say, 1000 psi? and maybe adjust or replace the hammer spring?

[GerryR]

is there a way to adjust the reg to say, 1000 psi? and maybe adjust or replace the hammer spring?

I have no idea; I doubt at this price point that they left anything adjustable, but I could be totally wrong.  I don't have an exploded view of the gun, either.  I'm new to air guns, so wouldn't know where to start in any case.