Kral Arms A question for you "Unregulated PCP tuners"

[Emu]

In reference to my Kral Super Duty project.
See: Kral Project

Lightened the hammer, changed hammer spring and some minor trigger work sense last time.

Here is what the shot profile is looking like with a 1500 psi spread going from 3000 down to 1500 psi.
* Actually done on a fill stopping at these pressures and chrony testing.

1500 psi is 849 fps
2000 psi is 903 fps
2500 psi is 880 fps
3000 psi is 845 fps

So we have an ES of @ 55 fps in this unregulated 1420 cc capacity air beast as currently tuned.
I'm thinking for the quantity of shots there is going to be that it is very doable for an open field 100's of shots per day squirrel whacker !!!

So for you unregulated guys .... how is this tune ? ( I'm a regulator tuner and this was very time consuming )

Thanks,
Scott

Easier way:

-> Do not tune anything. Just learn how to compensate along shot string.

 

[nobody1]

In reference to my Kral Super Duty project.
See: Kral Project

Lightened the hammer, changed hammer spring and some minor trigger work sense last time.

Here is what the shot profile is looking like with a 1500 psi spread going from 3000 down to 1500 psi.
* Actually done on a fill stopping at these pressures and chrony testing.

1500 psi is 849 fps
2000 psi is 903 fps
2500 psi is 880 fps
3000 psi is 845 fps

So we have an ES of @ 55 fps in this unregulated 1420 cc capacity air beast as currently tuned.
I'm thinking for the quantity of shots there is going to be that it is very doable for an open field 100's of shots per day squirrel whacker !!!

So for you unregulated guys .... how is this tune ? ( I'm a regulator tuner and this was very time consuming )

Thanks,
Scott

For me, the best way to get a flatter shots string (in an unregulated PCP) was using a 3D printed buffer tuned to the airgun.
The buffer (similar to BStaley) is 3D printed from TPU (flexible, rubber like material).
The buffer goes between the hammer and the face of the valve.
It prevents the hammer from hitting the valve stem too hard.
This buffer trades more power for more shots.
It takes a few hours to find the right buffer height to get the shot string I want.

But with 1420cc of air I would not worry about tuning

 

[Vetmx]

I started yapping in my last post and never gave any true input. Every unregulated gun I’ve ever owned or set up came with at least a 3k psi rating. I’ve never once finalized my best settings by filling to 3k. The only exception was this little .30 AEA blast cannon I had. But that was a different animal. A 12“ barrel and big caliber required me to really mess with hammer strike and porting but I still had a pretty steep curve going up and back down. Just going off your numbers I’d fill the gun to 2,500 and refill at 1,600. If you have the hammer bounce that Krals are known for under control, I think you nailed it. This is how the gauges on all my unregulated guns look. I have too many guns and some go long periods without being shot. No way I can remember and hate digging through my notebook.

 

[nobody1]

I started yapping in my last post and never gave any true input. Every unregulated gun I’ve ever owned or set up came with at least a 3k psi rating. I’ve never once finalized my best settings by filling to 3k. The only exception was this little .30 AEA blast cannon I had. But that was a different animal. A 12“ barrel and big caliber required me to really mess with hammer strike and porting but I still had a pretty steep curve going up and back down. Just going off your numbers I’d fill the gun to 2,500 and refill at 1,600. If you have the hammer bounce that Krals are known for under control, I think you nailed it. This is how the gauges on all my unregulated guns look. I have too many guns and some go long periods without being shot. No way I can remember and hate digging through my notebook.

View attachment 564235

Good idea of showing only the "good" part of the pressure gauge.

Recently I started keeping a log of airgun tunes.
Now I know which pressure to start with and how many good shots I get

 

[Motorhead]

Easier way:

-> Do not tune anything. Just learn how to compensate along shot string.

Sadly not realistic ... as days spent getting the experience of having no clue is how to correct with misplaced shots is not replaceable with another similar day.
Getting ones sh it together kinda needs to happen in the moment and not some fantasy couda wouda shoda sequence of misplaced confidence miraculously coming together.

 

[JackHughs]

I'm not an expert in either regulated or unregulated airguns. I did record some interesting data from my unmodified KRAL manufactured Benjamin Kratos that gave me a greater appreciation for these unregulated airguns. There is no bell shaped curve with this rifle. Starting at 3,000 psi, MV's are flat down to about 2350 psi. I assume that this is due to a transfer system that is designed for full flow at about 2400-2500 psi. At higher pressures, the transfer system will "regulate" mass air flow to the 2400-2500 psi equivalent.

Thanks for sharing all the info on your KRAL build. It's great to learn new things.

JackHughs