Just a heads up, it may be a commitment for a lot of people to get the xprt90 running as expected. You might want to lower your expectations.
As you know the ps90 has a progressive trigger with the first stage a half pull for single fire and a full pull for forced rest. I have been facing two main issues.
The first is I keep getting unintentionally forced out of the 2nd stage leading to very short bursts. You may be tempted to say just pull back further to give yourself a bigger cushion.
Well that leads me to my next problem. If I pull back too far the moving parts group gets stuck back or the forced reset gets jammed.
The sweet spot not only seems very small but I have to be extremely conscious of not letting the forced reset push me out of the 2nd stage.
Yes it's installed correctly and yes it's very well lubed and I've shot 600 rds out of it. I really hope it's not fully broken in yet or it's a skill issue because I can fix a skill issue but I can't fix spending a lot of money on a frt with a tiny sweet spot.