Tuning Kalibrgun Argus Maintenance

Anybody have experience in regular maintenance for the Argus? The manual is vague and without pictures. Internet search didn't find anything regarding this particular gun. I have shot about 1000 pellets and the only thing I did so far is to clean the barrel with patchworm and ballistol after 500 shots. I am not looking for full disassemble of the gun to lube all the moving parts. I am just looking regular maintenance. I have attached a screenshot of the manual and hope you guys can give guidance.

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My brand new Kalibr Argus .30cal from Krale was shooting JSB 44.75gr 690fps from the factory. With hammer spring maxed to the max it will get up to 790fps. I shot almost an entire tin through the magazine before the gun fell off the reg around 90bar, so the reg is way off from what it is supposed to be. I'm awaiting news from Krale on what to do about this, but as it stands right now, I am NOT TO FREAKING HAPPY! 😤
 
Ouch. According to Kalibrgun USA website, Argus .30 cal is supposed to shoot 915fps with 44 grain. There is a video by Airguns of Michigan on YouTube that talks about his Kalibrgun Tactical shooting below velocity whether he turn the hammer spring to the max or down, it just stayed the same. He took his gun apart and found the barrel to be misaligned with the transfer port from factory. Not saying that's what's happening with your gun but could be a possibility. Video below and starts at 21minute mark. 



https://youtu.be/LyXAMTtwYIg