Tuning Tuning regulator - can you have a reg set too low?

[Dairyboy]

I also like the efficiency of the .25 caliber compared to the .22 caliber. For comparison, My Standard Veteran .22 with a 30 FPE tune was getting 50 shots on the regulator.

I can't remember ever doing a shot string on my Standards but that seems low. For comparison my Taipan Vet Short at 900fps with 16gr got 45 shots on reg. Throw in 18gr and your at 865fps for 30fpe and maybe gain a shot or 2 for efficiency gain.

Taipan Veteran Shorty .22 shot string with Veteran Standard .25 shot string

No secret why I love these guns Created: 07-16-2017 10:01:33 AM Description: Taipan Veteran .22 Shorty Notes 1: 250bar fill reg set at 120bar Notes 2: Distance to Chrono (FT): 2.00 Ballistic Coefficient: 1.000 Bullet Weight (gr): 15.890 Altitude (FT): 0.0 Temp: 69 °F BP: 30.15 inHG Shots # ...

www.airgunnation.com

My Long then got 85 shots on reg at 950fps with 16gr. With 18gr would probably get 90 on reg.

https://www.airgunnation.com/threads/taipan-veteran-long-22-shot-string.364559/

I would expect around 70 shots on reg at least from a standard at 30fpe. I wonder if dropping your reg caused efficiency issues. Likely hammer too heavy for said reg pressure. Which also makes sense with the whole point of this post having a reg set too low.

Taking a gun designed with regs in the 120-150 bar range and taking them to well below that, other things need to be changed like hammer weight usually.

 

[MushroomPsyche]

I can't remember ever doing a shot string on my Standards but that seems low. For comparison my Taipan Vet Short at 900fps with 16gr got 45 shots on reg. Throw in 18gr and your at 865fps for 30fpe and maybe gain a shot or 2 for efficiency gain.

Taipan Veteran Shorty .22 shot string with Veteran Standard .25 shot string

No secret why I love these guns Created: 07-16-2017 10:01:33 AM Description: Taipan Veteran .22 Shorty Notes 1: 250bar fill reg set at 120bar Notes 2: Distance to Chrono (FT): 2.00 Ballistic Coefficient: 1.000 Bullet Weight (gr): 15.890 Altitude (FT): 0.0 Temp: 69 °F BP: 30.15 inHG Shots # ...

www.airgunnation.com

My Long then got 85 shots on reg at 950fps with 16gr. With 18gr would probably get 90 on reg.

https://www.airgunnation.com/threads/taipan-veteran-long-22-shot-string.364559/

I would expect around 70 shots on reg at least from a standard at 30fpe. I wonder if dropping your reg caused efficiency issues. Likely hammer too heavy for said reg pressure. Which also makes sense with the whole point of this post having a reg set too low.

Taking a gun designed with regs in the 120-150 bar range and taking them to well below that, other things need to be changed like hammer weight usually.

My Long .22 was getting around 90 shots at that power with the 15.89gr. Hades... So the same as yours. That was at 95 bars regulator.

I was only able to get 60 shots with the .22 Standard when I tuned it to 27 FPE at 88 bars.

For all the tunes, the hammer spring tension was set to give around a velocity of 2% less than maximum. I typically leave my guns at that hammer spring tension unless I see unexplained misses with easy shots with the "cold barrel" first shots.

But yes, I agree... The Veterans are designed for around 135 bars regulator (factory setting) and I'm finding out now that they don't do too well at pressure much lower than that.

I've taken some squirrels with the Short at 95 bars pressure and it seems to be good to go now. It's now hitting exactly where I aim; at distances of around 30 meters.

 

[MushroomPsyche]

I don't understand the concept of tuning a rifle to a set FPE. isn't it true that for each barrel/pellet combination, there exists a MV range that yields best accuracy? And, if so, wouldn't it be best to test various pellets and simply adjust the regulator and the hammer spring until best accuracy is achieved?. Then calculate the corresponding FPE.

JackHughs

As was already mentioned, there are several zones where individual guns will find their harmony.

I'm my case, I tend to focus on FPE (maybe over focus? ) because my guns serve as suburban varmint rifles. I'm trying to balance the safety and power for taking pests as humanely as possible.

 

[JackHughs]

Yes, there's a bit of truth to that, but a barrel/pellet combo will, in most cases, yield several "ideal" tunes. Think of tunes as ranges of fpe or velocity. The harmonics of a barrel, for instance, can be on several nodes, it's not just one single node that magically works. kind of like a sine wave when it hits zero, there are several zeros along the time line.

I don't dispute your assertion of multiple accuracy nodes. It's just that I've never encountered such nodes.

I have an Impact for pellets, a Panthera for slugs, and I'm currently having fun gathering data with a Benjamin Kratos. Althought the Kratos is not pressure regulated, it has a valve in the transfer system that regulates mass airflow into the chamber. The valve allows for tuning at different maximum muzzle energy levels. Future testing will include looking for multiple accuracy nodes.

JackHughs