Tuning a reg'd S510 for FT. Powerwheel or turn the reg down? or???

[MonsterMaxx]

I'm going to go to a FT event in the end of October. While my addiction to buying new guns is pretty bad, I really need a big CF bottle next (for the thirsty Impact .30) so budget for a new gun & glass isn't really there.

My S510 is a .22 carbine and Huma regulated at 145bar. Shoots an 18gr jsb at around 860fps. It's a tack driver at 25/50yds and does quite well at 75yds too. I figure with a lighter pellet and a bit of tuning I can compete with it and not have to use someone's loaner or buy something new.

I found some very lightweight H&N 10.03gr domed pellets which will allow 945fps speeds and still be legal for FT (20fpe). H&N states on the specs it's max distance is 30m. IDK why. Seems to be a few different versions of this pellet, as mine are 10.03, but spec is 9.57gr. Got them from Amazon as everyone else is out of stock. Spendy!
https://www.hn-sport.de/en/air-gun-hunting/field-target-trophy-green-22


Shot the first ones over the chrony w/ no other changes and hit near 1100fps. Not only over power limit, but I doubt the pellet will fly well.

so I turned the power setting all the way down and got 487fps. Too slow.

W/ the power right where it catches the detent and it's marker is near vertical it's shooting in the 920fps range.

Sighted at 25yards it's pretty darn good, but when I open up to 50yds some are good, some are wildly bad.

It's a little gusty here today, but I'm trying to shoot during the calm parts, based on what I'm seeing it's not the wind that's causing pellets to go high, then low.

So I'm thinking that the restriction of the power wheel is causing turbulence in the chamber and I'd be better turning the reg down to something like 120bar and open the power wheel back up all the way.

Any suggestions, thoughts or ideas on how to get this .22 tuned up for FT?

 

[Guest]

First try turning it down to 880fps in ten fps increments or so and shoot a 50yd group each time. If slowing things down doesn't do the trick maybe try14/15gr pellets. Don't worry to much about the speed as accuracy is what you're looking for.

As for tuning the gun stick with the power wheel for now and go shoot the match. After the match you will likely want a .177 so don't go making drastic changes to your .22

 

[sirk]

man thats wrong. .25s have such high reg pressure typically.
i would not go higher than 120 for a .22 even for normal power setup
for low power setup do this:
fill the gun only to 145bar in the cylinder(whatever is your reg is set to currently)
then setup the hammer spring with that little air in cylinder by undoing the hammer spring adjuster. 20fpe seems to work out around 790fps with jsb express 14.3grain (chrony work).

then fill the cylinder fully and check the fps again. IF the fps stays constant, you can leave the reg alone (which is unlikely). if speed/power drops (there is unbalance between the reg and hammer setup) when cylinder if full you MUST reduce the reg output setting to lower.

my guess is you have to go closer to 100bar. who told you to run a .22 at 145bar?

regarding the power wheel, if power is too low on the lower setting maybe you can enlarge the hole/ reduce the restriction a wee bit and perhaps you can keep your unusual high reg setting

in my experience it is better to have 2 different dedicated guns, instead of messing around. This will prevent some major headaches in future like wandering poi etc.

 

[terrymc]

So here are my thoughts.
First the regulator pressure is too high.
I have a lane regulator and it is between 125-130 my 510 is a long gun so I get a little more velocity however even at 125ish bar I get 30fpe from 18.1 jsb's.
At your pressure you are wasting a ton of air. My hammer is 39 grains instead of the stock 50-51 grains it has the stock hammer spring. The combination allows for 40 shots before falling off the regulator.
This should give you about the energy you are starting with maybe a little less due to the carbine.

to lower the velocity, I would buy a second hammer spring and trim coils to lower your hammer strike.
other guns you can lower the preload but the s510 does not offer that.
the problem with the power regulator is getting the setting consistent.
Also you do not gain a lot of shots with the adjuster, but the hammerbspring will significantly increase shot count.

This is all information that I got from a lot of digging around

just my thoughts.

 

[Guest]

Guys, please remember that he is going to use it for a(not all) FT match. There is no point in making drastic changes to a gun he will likely not use for FT in the future. Great suggestions though for power and shot count tunes.

sirk: If you knew about AA S series guns you would know that there is no room for increasing the transfer port that is part of the power wheel. You would also know that changing tension on the hammer spring requires spacing(which you get very little of) or removing coils/getting another spring all together.

Max, I will stick with my suggestion that you get it set with the wheel and then go have fun at the shoot. Don't worry about tuning it until you are sure it will be used for FT full time.