Just a bit of an update. I am playing with Vortek kits.The HO kit is stiff and jumpy out of the box. But the shot cycle is awesome and I love that sharp "TCHAK" cycle. It iOS shooting 14.5-15fpe with heavies (CPH, Baracuda Match) and 15-16 fps with lighter fare. I think one coil off may tame the beast and make it more accurate in my hands. At this level it is not a bag rest rifle. I tried a low output (12 fpe) kit. It is shooting 11-11.5 fps, so right on the money. Much milder of course, but I don't like the shot cycle as much. I get better accuracy of course.The low output kit with one 1/8" metal washer and one delrin ARH washer reaches 12.5-13 fpe. I like the cycle a little better with that added preload and piston weight.Basically at low output I feel that the cycle is not that great and I am holding the gun back. At high output I love the sharp quick cycle but am not getting good enough accuracy.I have a shot stroke kit coming from TbT in the next few days, I want to experiment with that with both the low and the high output Vortek kits, see how the gun responds.For now, she seems to be settling on Baracuda Match 10.65Gr, Baracuda FT 9.57Gr, and FTT 8.64Gr in that order. She does surprisingly well at least at shorter distances with the Crosman Premier Heavy. I haven't tried that one too much to not mix leads. I think the gun likes heavies better (but sprays AA 10.3Gr like birdshot). everything I try under 9.57 Gr doesn't do too well.I will keep playing. If the short stroke kit does not yield good results, I will trim the high output Vortek a bit, I would like to keep this gun around 14fpe with a milder cycle so I can bench rest it if I want to.This is fun.To finish for today, here are two targets shot at the end of the day with Baracuda Match at 59yards, shouldered with forestock on a bag with the low output kit and washers. those are very good for me. 10 shots each. On the first target there are actually 11 shots, the stray one on the right side of the group is a called pull.I am loving this thing. She might end up needing a name.CheersA.
FYI: My HW98 in .177 prefers the H&N FTT 8.64g in 4.52 head size.YMMV
Having a long slow shot cycle to decrease power doesn't appeal to me either. You should be able to get good accuracy in the 14.5-15 fpe range with that gun. It will take a little bit of concentration but you'll still have a nice quick shot cycle.
Be careful that the gun isn't dieseling. Dieseling will tank your accuracy. It's also more prone to dieseling at higher power levels. Dieseling is sometimes the accuracy thief and not the increase in power level.
I have a 15 fpe 177 Hw95 and a 16fpe 20 caliber R9 that shoot very well at those power levels. I feel it's in part to the fact I build clean running guns. I'm currently wrestling with a Vortek kit and a 22 Hw95 and I'll see how that one works out.
Sounds like you're enjoying your gun. Keep us in the loop. I'm curious about the the details and results of your destroking efforts.
Ps stay away from the Crosman and try some more mid 8 and 9 grain pellets. Those guns usually loose efficiency with heavy pellets. That efficiency loss is usually due to piston bounce which can hurt accuracy as well.