Top Hat Adjustment / Power Wheel and wasting air
I just read the post Adam placed in the Quick Reference section from Tim at Mac1. Tim has found that the typical best tophat setting is 0.1 inch. This is opposite of what we see in the Tophat adjustment sticky which says the factory setting is too high and to start at .07.
I have a stock talon SS .22 cal. I got my chrony a few days ago and have spent much time adjusting the tophat. I have gotten good numbers (about 750 fps at the lower tophat settings) all the way down to a tophat setting of .05 inch. (I did see the phenomenon of POI shift at these smaller gaps when the tophat started to bottom out on the valve).
I did just try the 0.1 inch setting as suggested by Tim from Mac1. This is by far the largest tophat gap I have tried. Here is what I got with my tank filled to 2700 psi. Shooting Benjamin Discovery 14.3 gr.
Power Wheel – fps
2 – 515
3 – 585
4 – 664
5 – 735
6 – 770
7 – 797
8 – 796
9 – 801
As you can see PW setting 7 is the highest I can go with this setup and not start wasting air. And if I can dial down to between 3 and 4 on the PW I could virtually have a micrometer tank. Seems like a nice spread of velocities.
The bottom line is that I believe that with a chrony you can use various tophat settings and combined with the powerwheel find the point where the velocity levels off and you begin to waste air. I have gotten these pellets up to 825 tops in my gun using all types of various settings. I believe that low 800’s is about the tops for these pellets and a 12″ barrel.
As long as your O-Rings are good on your breech, it only takes a fixed amount of air to move a pellet to a certain velocity and whether your tophat is set low or high as long as you can measure where the speed tops out for your particular setup – barrel and pellets – you are probably using the air efficiently. I think that is what Tim is saying in his post, that you can drive yourself crazy trying to find the sweet spot.
The only thing I have not done yet is to count shots using various tophat settings and staying around this same velocity. When I do that I will let you know the results. If I can get the same number of shots before the velocity starts to drop off using a combination of tophat and PW settings then I will have proven my theory.
PS – I am having fun figuring this all out and yes Buzzcat we will share the chrony!
Greg
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Do you have the old valve?? Send it in an get the new one, you’ll be able to operate on a full tank, you’ll like your Condor much more…
Talon SS, 18″ barrel, 0.177cal…
Tophat Gap= 0.09 Each shot uses 50psi of air… Velocity at 950 fps…
Tophat Gap= 0.066 Each shot uses 15psi of air… Velocity at 950 fps…
Why would I want a tophat setting that produces the same velocity but uses less than 25% of HPA?
I have a pump… 😉
Another reason, I get to shoot four times longer until it is time to break the beast down and refill…
Why would I want that??? 🙄
For me THE value of tophat adjustment is to attain more shots per fill… One could always reduce the preload until consistency is attained…
Sam as you can see in the pic there is quite a bit of difference in the girth of the vales.
Thanks GTBJ. In the pic it looks as if the inner part of the valve (where the air actually come out from) stem is the same thickness as the condor valve. Which is to say, pretty thin and delicate. Well lesson learned for me and my fat hands lol. Thanks again GTBJ.
Sam as you can see in the pic there is quite a bit of difference in the girth of the vales.
If you want a new one call AF and order one and I don’t know if there is a difference, I would not doubt it though.
Are the stems of the talon tanks more robust the the “hi-flow” condor tanks? Because I damaged my stem from over tightening the top hat.
I’ve always had my .22 condor setup to shoot from 1800 down for about 25-30 shots at ~980fps. Its actually the only way I can get my gun to work well. I like it. I recommend it.
O.K. I was running the same test as above post and they did not turn out the same, I got like 20 -22 shots from like 1875 to 1600psi. the shots were from 944 to 962 the point or impact seem to be the same, I’m liking this set up, do to less pressure and less pumping.
Yeah after visiting Tim’s shop on several occasions, you’ll find it’s really never his goal to simply get the most power out of a gun, he’s much more interested in setting up a gun for effieciency, shot count, accuracy ect, with power being whatever it ends up being after his tune up. So to him power is more of a secondary thing. I don’t even think he sells Condors with the hi flo tank unless a customer insists on it. Bigger power with just 20 some shots is something that doesn’t appeal to him personally, especially if he feels it’s harder to tune, so he’ll try to talk customers into the Talon tank, but it’s still the customers decision of course.
First off, I think some guys are working for different goals. Tim says he’s looking for “the best accuracy and shot effieciency”, I suspect some folks are looking for brute power? If you note he suggests farily modest power levels (20 fpe with 12 inches, 25 with 18, 30 with 24 inch ‘Talon or Condor’). He’s looking for 40 or more shots within 30 or 40 fps of each other.
Secondly, he says “Once you have the gun’s wheel setting giving this situation you can use the valve head adjustment to adjust the power up and down for various pellets and usage.” I don’t read this as saying ‘leave the TH at .100’. As I read this it’s a two step process, set the fill pressure and PW with the TH wide open (so it has no effect), then reset the TH (which doesn’t change the other two settings) like say a Career does.
He also states no two guns or tanks behave the same, as have others here. IMO there’s a lot of experience out there for us to profit from. It’s worth listening to folks who’ve been there. It’s also importatnt to understand the goal, the tune Tim is looking for may not be what you want.
Doug Owen
.25, condor, with the valve stem port holes squared out the rest is stock
What is your setup? Any mods?
I was playing today of course and with the tank pressure below 2000psi., I was shooting, pw 0, crow mags 26gr. at a constant 950fps.-960fps., for a total of 25 shots, ending with 1450 -1500 tank pressure, my top hat is set at .078.
Buzzcat,
If you haven’t seen this yet,,,,,, It will give you a small headache:
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Tophat set at 0.1 – getting 800 fps with PW set at 7
Per my post above the velocity levels off at higher PW settings for both. Therefore I believe I am using the same amount of air for both settings.
Greg
Not so…
Fill the tank, note the pressure, fire off 20 shots at 0.1 then check the pressure. Then do the same at 0.055 with the PW wheel left alone for both shot strings.
You will notice that the 0.1 will use about twice (or more) the air to shoot the same amount of shots…
In fact using more air will be the only thing that changes… (Well that and the fact that with the smaller gap the variance between the shot velocities is reduced…).