Expected Velocity for TX200HC (with Vortek PG2 SHO kit).

I purchased a TX200HC about a year ago from PA. The gun is beautiful, but it was really not very accurate (1" @ 15 yards). The velocity was also pretty low (.22 14.3g @ 580ft/s). The gun was pretty buzzy, but not as noticeable as a RWS Model 48 that I had shot (48 was noticeably more accurate). I decided to try the Vortek PG2 SHO kit. The results are pretty amazing for this rifle. The rifle fires much smoother now with no buzz and the accuracy is greatly improved (shooting 1 ragged hole so I now need to move out to 30 yards or so to do some accuracy testing). Velocity with the 14.3g Premiers is now averaging 660ft/s. Energy with a number of pellets is ranging from 12.12fpe to 14.65fpe depending on the pellet. Vortek advertises 15-17fpe. I am relatively happy with this and think it has the potential to be a fine hunting rifle for close range (hoping for 40 yards).

Now, here are my questions. What velocity/energy do others get with a TX200HC (USA)? While I can certainly use the rifle at this power level, is there anything that I should look at to get the velocity up further (perhaps will come up as the seal wears in)? I will probably change the barrel o-rings, but wanted to know if the rifle is already providing the energy that it can. 

​Probably unrelated: The only other observation I can offer is that sometimes the safety doesn't engage. If I re-cock the rifle fully, it then does set. Perhaps I must be careful to watch the safety engage on every cycle.

Here are some velocity and energies that I see now.
Premier Domed Ultra 14.3g, Avg 666.8fps @ 14.12fpe
AA Diabolo Field 16g, Avg 595fps @12.58fpe
RWS Super Point Extra 14.5g, Avg 674.5fps @ 14.65fpe.
JSB Diabolo Straton Jumbo 15.9g, Avg 597.4 @ 12.71fpe.
JSB Diabolo Exact Jumb RS 13.4g, Avg 639.3 @ 12.19fpe

 
I purchased a TX hc a few months back. I believe it was shooting 15fpe ish when I received it. I strongly disliked its shot cycle so I also installed a pg2 kit, however I purchased the 12fpe kit. I also installed a TBT piston extension. If it were me, I wouldn’t worry about gaining any additional power. There really is no added benefit to gaining 1-2 fpe. Just a harsher cycle. I routinely take small game out to 50 yards and all my springers are sub 12fpe. That’s more a testament to the mellow “recoil” than anything to do with me. I believe my older rifles did increase slightly over time, but if you’re happy with it now I wouldn’t worry about an increase in power. Rest assured, it can easily take game at the distance you mentioned 
 
Your numbers sound a little on the low side with the heavier pellets. Might want to check for a leak at the compression chamber or the breech seals. I have run both the SHO and 12fpe kit in my .22 TX. The shot cycle is less jumpy with the 12fpe kit and with that said it is more accurate for me. Your safety not setting each time, check and see if your front stock screws are hitting on the cocking lever. If they are just file them a little shorter. 
Right now I’m running TBT guides with a ARH piston and breech seals and the fac spring getting a little better than 16 fpe with AA 16 pellets. The gun is smooth to shoot and accurate. Out of all my guns the TX is my favorite. 
 
I spent some time shooting groups for accuracy this weekend with the TX200HC (Vortek). At 30 yards with a less than perfect rest, I'm now getting groups regularly around 0.8" with H&N FTT pellets. I am quite glad to see this rifle has improved so significantly. A solid bench would allow for even better groups.

I also learned that some of the issues I was having were due to a finicky UTG 3-12 Accushot scope that I had used. Getting good groups required tightening down the turret locks which made adjustments a bit unpredictable. I'm not too pleased with that scope so it is being replaced by a Leupold 3-9 EFR. 

Next steps: I will recheck the velocity, replace the breech seals with ones from ARH and again measure the velocity. I will also check the piston seal to make sure it is fitting well.