Talon SS power variation

The slow velocity is probably do the hammer chattering down the frame. Just put some dry lube and it will go away.

I use a spray dry lube for the hammer. I get it at the auto store

On mine, I would get those off-speed shots occasionally too. Turned out I wasn’t seating the bolt against the top-hat every time. Once in a while, I’d not pull it all the way back and it would misfire. Try purposely pushing the bolt forward before you fire it and see if it goes off-speed. That’s how I finally figured mine out.

I ended up making a new bolt handle and a brass spacer instead of the factory plastic handle and spacer. Hasn’t misfired since.

150 psi I could live with, I just discovered my fill gauge was off by 700! Now I have to relearn all my fill points, what I thought was 3000 was only around 2300. Other things to check would be top hat set screws, power wheel setting, and hammer lube. Sometimes a dry hammer will drag a bit, causing low power shots. BTW, from your description, it doesn’t sound like valve lock. In valve lock, velocity starts low then gradually rises as the tank pressure comes down. Finally, if it’s brand new, give it a little time. Sometimes these things just need to polish off a few rough edges. Good luck!

Dave