TT Tophat airdump; any suggestions?
So I just got one of the beautiful High Performance Tophats with the threaded inserts from Talon Tunes for my Condor SS. Super easy to install and really nicely machined. It works great with the large insert, shoots about like the stock tophat, a bit slower but with no inserts to come loose. My hope had been to get a little more power for heavy pellets (25-32gr) so I did some shooting with no insert today and keept running into problems with air dumps. First time was with a full 3000psi fill pushing out a EunJin 32g pellet: giant loud rush of air that left my ears ringing, face bruised from the scope, tank half empty and chronometer blown off the table 5′ away!
If figured this might have been some kind of one-time problem, maybe from an overly tight pellet, but it keeps happening. It seems to shoot light pellets OK (18g or less) but with JSB 25, EunJun 32 or Deadfish 32 I geep getting these big dumps; sometimes just a louder air rush but often the huge dump. My chronometer it taking a beating (survived 5 table-dives so far). Tried swapping back to the stock tophat, no problems. Tried lubing the TT tophat, no fix. I can shoot OK with the insert but then might as well be using the stock tophat (after a loctite job on the setscrews).
Any ideas/suggestions?
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Wow! What the hell caused that Walter? 😯 Any Idea?
Knife
Knife
First time was with a full 3000psi fill pushing out a EunJin 32g pellet: giant loud rush of air that left my ears ringing………………
Did I miss what psi you are shooting down to? too little pressure in the tank can cause a dump as well. The heavier the pellet, the more likely.
Knife
No the 32’s break the sound barrier with no insert. But that Mod is amazing!
Thanks for all the suggestions!
I’ve tried o-ring, different PW settings, making sure it’s seated well. Problem persists.
I love the TT tophat with the large restrictor; I can get 50+ good shots, very consistent and using little air; almost like having a regulated gun. Power is a little less than ideal; peak around 45-50ftlb rather than 60; still plenty powerful for most purposes. With the large restrictor it doesn’t seem to add anything having an o-ring behind.
Wondering if anyone had been able to successfully use the TT tophat with no insert on an 18″ .22 with heavy (25-30gr) pellets? I realized all the tests/reviews I’ve read have been with the .25. I wonder if it’s just too wide-open for the smaller caliber?
I ended up machining my own larger insert, a 1/4-20 bronze bolt drilled to just over 5/32. This gives slightly more power than the stock valve and lets me easily swap down to the large TT restrictor for more shots without having to change tophats. Need to run some strings with each restrictor to compare but feel like it’s about as close to dialed-in as I need. Now if some of those wild turkeys would just come by….
Did he say “ANY SUGGESTIONS” 😆
OK, here’s some cheap tricks…..
“CHEAP” refers to probably won’t work but is worth a try before you have to bust loose the tank and valve body.
#1) Yep, put an o-ring #010 or #011 behind the top hat.
Why? Becuz there may be a bad balancing act between the hammer spring and the valve spring.
Effect, if lucky, it might lessen hammer bounce giving the valve spring the upper hand.
It’s cheap and may assist cheap trick #2 or cheap trick #3.
#2) Increase the Power Wheel hammer spring preload.
Why? More can dampen hammer bounce.
#3) Last ditch effort as nothing else is simple and requires work and diving in deep, SO, with cheap trick #1 still installed, try lowering the PW setting. Go for broke, all the way to zero.
Not enough preload on the return spring. Take the valve out of the tank and see where it’s at.
Heavier the projectile the longer the valve will stay open unless more preload or a stiffer spring is used.
I just put on a hammer slap mod today and the TT Top Hat with inserts. I did not experience any rushes of air (dumps) but I was shooting .25 caliber not .22 caliber. To me it looks like this valve with the big insert is going to be great in .22 caliber with JSB 18.13 Exacts Heavy Jumbo’s. Make sure the valve is in correctly. My first shot off a full tank on full power on the wheel was 1045 with 43.2 EunJins serious power. 104.78 fpe. They went down from there but the valve wide open eats some air and then again it tosses lead down range with serious power.
Oakey
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Found a usable solution: adding an O-ring behind the TT tophat lets me shoot it with no restrictor without getting those nasty air dumps. Damps the power down a bit from the stock valve (50 vs 60ftlb with my favorite Deadfish 32 pellets) but more than makes up for it in improved shot count and consistency.
So I seem to have settled on a pretty good tune for my Condor SS: TT spacer with O-ring, home-hammer-slap-mod (rubber washer glued to front of breech), PW10.1; no restrictor with 32g pellets, large restrictor with H&N Barracudas. Going from 3000 – 2000 psi I get 40 shots around 50ftlb with the 32gr pellets and no restrictor, 60 shots with the H&Ns around 30ftlb and happily tight (a lot of 3/8″ groups at 40 yards). Can’t complain!