taipan veteran tuning

I not see where to said what size veteran you have. I have a .25 standard ukraine,a.25 long CZ and a.177 CZ made. Both of my .25 caliber guns shoot tight,but my .177 does as you gun. I just eran my long over my airchrony at max spring and got E.S. of 12 F.P.S. and average of 906 F.P.S. with 34g JSB's and 1020 F.P.S. with a E.S. of 9 F.P.S. It comes off the reg. at 150 bar. The standard is set at a half turn back and averages 957 with a E.S. of 5 F.P.S. at 150 bar. The .177 came from Talon Tunes with shot string that was tight with 8 grain pellets in the upper 900's with the spring adjuster backed way out. I cranked it up to max and shot 16.2's and would get a high and then a low just like you are getting. One thing that narrowed down what the problem was was it was consistent, high, low, high, low. I shot it down till it came off the reg. at 110 to 115 bar. The .177 has a lighter spring, but still more than what is needed to open the valve. I turned the spring back two and a half turns and got a nice string at 925 with 10.34's. I adjusted the spring up until I got to 945 average with 10.34's and 830 with 13.43's. In my case I had more spring than pressure. The reg and hammer strike were not balanced. You might try this with your gun. Go back three turns from where it just cocks and see what happens before you buy a new regulator. You might just need to up your reg. set point. I left mine as is since I get a ton of shots and have four other .177,s that shoot 16.2's at 910 to 980. Clem Slump,out?
 
Is there a specific huma regulator size i need to buy for taipan long or is this the proper one? Wanna make sure before i order it. Ive done so much testing and i honestly think the issue is getting worse over time the i thought maybe it could resolve with more break in but seems to be doing the opposite so i'm just gonna have to put in the regulator ive never degassed or dissembled a pcp so thats the only thing im worried about

https://talontunes.com/shop/taipan-veteran-huma-regulator/