Another Akela tune

[Benj312]

Here is the first shot string from my Lane reg. equipped .177 Akela. The hammer spring is cut down and the Lane is set to 95 bar. My original target fpe was 15. I really did not have a shot count in mind, but just wanted something more than 60. Using a cheap Amazon chrono but it does seem to work well. I shot maybe 60 shots, and adjusted the hammer spring to 1.25 turns in. I then shot the attached 175 shot string. I am happy with the results, but it can't be optimized unless I really lucked out.

Like an idiot, I tore the Akela apart to work on it before I fired a shot, so I have nothing to compare.

Any thoughts about the string would be appreciated, as this is my first time.

Also, I am not sure what caused the 5 or 6 low, single shot fps dips. Maybe deformed pellets, maybe a cheap chrono, maybe me resetting the chrono because it only holds about 35 shots?????

Is there a next step from a tuning perspective, or just go and shoot it? I did have fun using Sub12's video as a guide!

Joe

 

[BigTinBoat]

Based on the shot string you should be able to back off the HS just a bit and keep the same FPS. This will result in it being quieter, more efficient and usually a lower ES.
I come to this conclusion as you have no rise at the end of your string. If you are tuned on the down side "knee" of the peak velocity you should see a slight rise in FPS as the gun is coming off the reg.
A basic explanation is that if the reg s set at say 95bar, and you "tune" the HS to open the valve max at like 90bar, then as the pressure the valve is seeing drops to 90bar you will see the FPS rise.

 

[Benj312]

Based on the shot string you should be able to back off the HS just a bit and keep the same FPS. This will result in it being quieter, more efficient and usually a lower ES.
I come to this conclusion as you have no rise at the end of your string. If you are tuned on the down side "knee" of the peak velocity you should see a slight rise in FPS as the gun is coming off the reg.
A basic explanation is that if the reg s set at say 95bar, and you "tune" the HS to open the valve max at like 90bar, then as the pressure the valve is seeing drops to 90bar you will see the FPS rise.

BTB - Great Feedback. I'll back it off a 1/2 turn and redo the string. At this point, does it make sense to fill to something less than 3000psi? My assumption is that you can still see the rise if filled to 2000PSI and shoot down from there. Saves time and pellets. Also, can you share or link to a string that shows what you described?

 

[Benj312]

BTB - Great Feedback. I'll back it off a 1/2 turn and redo the string. At this point, does it make sense to fill to something less than 3000psi? My assumption is that you can still see the rise if filled to 2000PSI and shoot down from there. Saves time and pellets. Also, can you share or link to a string that shows what you described?

I ask for an example, because to a novice like me, there apepars to be a drop, then a rise towards the end of the string.

 

[BigTinBoat]

I ask for an example, because to a novice like me, there apepars to be a drop, then a rise towards the end of the string.

View attachment 296445

You don't have to fill all the way. By rise I mean a rise above the highest velocity.

You can always fill the gun, turn off the air supply, but don't bleed the line. Then you can use the fill gauge to monitor the cylinders pressure and see when you are getting close to the regulator pressure.

 

[orangeokie]

Based on the shot string you should be able to back off the HS just a bit and keep the same FPS. This will result in it being quieter, more efficient and usually a lower ES.
I come to this conclusion as you have no rise at the end of your string. If you are tuned on the down side "knee" of the peak velocity you should see a slight rise in FPS as the gun is coming off the reg.
A basic explanation is that if the reg s set at say 95bar, and you "tune" the HS to open the valve max at like 90bar, then as the pressure the valve is seeing drops to 90bar you will see the FPS rise.

For newbies like me, what is "HS" and how does one "back off" a bit? Thanks. I bought a Huma regulator with intentions of installing it in my new Akela .177.

 

[Benj312]

HS refers to the hammer spring. On the Akela, it can be adjusted in or out.

 

[Vetmx]

Your weird downward spikes could be a junker pellet but why would they all be slow? But it still could be. Another thing it could be is you are getting reg creep. When you pause long enough to load mags or mess with the chronograph, your set point climbs just enough that your hammer setting can’t overcome that first shot. Don’t sweat it, just keep an eye on it if those spikes get worse. Also, when you show a string online and truly want help, make sure you record the first shot of the day in that string. Getting a gun warmed up before posting a string on a forum is cheating. They don’t tell a true story about just how good or bad you gun and tune are. You are on the right track.