Couldn't resist buying one when they were on sale for R3500 .... Figuring it would be a great project rifle.
Initial impressions were positive... Build quality is good, machining and materials used are top notch.
I quickly realised there were some issues when testing started.
Rifle was extremely loud for the velocity... 855fps with JSB 18.1 gr.... It was an absolute air hogg...only 18 shots from 200 to 150 bar... Accuracy was terrible about 5cm groups at 20m.
First mod was to manufacture a hammer debounce device. A softer hammer spring caused excessive hammer bounce.
I used Sustadur PET plastic for the parts instead of steel too keep the moving mass as low as possible.
6mm less preload than factory settings.
A lot quieter!.... There's way to much hammer strike with factory setup for a regulated rifle.
Velocity still 855fps fps, but shot count now 30 from 200 to 150 bar.
I was puzzled why the reg was set at 150 bar, removed it and measured the plenum volume... Only 10cc! Way to small for 30fpe.
The only way to property set up this rifle with the reg for 30 fpe and lower reg pressure +-120 bar will be to increase plenum to 20 or more cc.
I'm going to replace the barrel, but wanted to see what improvement I could make to the standard barrel.
The leade was extremely tight...
Sizing the pellets excessively... After the first 3cm the pellets would fall freely through the barrel, only stopped by a slight choke at the muzzle.
I removed the tight section.
Shroud was slightly off-centre... Re-faced the threaded attachment while secured on the barrel.
Accuracy is now acceptable. Velocity dropped to 845 fps... I turned velocity down about 10 fps from max before shooting the string.
Groups shot at 36m... Left is 15 shots.
There's regulator creep present... If the rifle is left fully charged for a few hours the first shot will be drastically slower.
I inspected the parts under a microscope.... The white valve discs is badly machined and probably leaks where it seals against the set screw.
I'll consider rebuilding the reg and making a larger plenum, or just remove the regulator.