Taipan Quirk with the vet 1

[rangur1]

I know at least 5 guys who can answer this one. My 5 year old venerable vet 1 has this odd issue. When I fill to 230-250 bar, my shots are not as powerful. When the reg lowers towards 200 bar, the power increases, raising my POI. But from say, around 205 bar down to the reg pressure, shot strength is as consistent as you would expect. Is my reg getting worn/sloppy? It’s a huma, about 2-3 years old.

 

[Vetmx]

Where do you have the hammer set in relation to your plateau speed. If you are in the proper 3-5% below then we will have to dig deeper.

 

[rangur1]

Where do you have the hammer set in relation to your plateau speed. If you are in the proper 3-5% below then we will have to dig deeper.

I doubt I'm even close to that. This gun is got a heavy hammer spring, reg at 150 with a plenum capable of 70-73 foot pounds for slugs. But I loosen the hammer spring for low power pesting around the property. Those big adjustments must be affecting performance, just figured the effect would be even from 250-150 bar.

 

[PasadenaMike]

Chronograph is your friend.

 

[Vetmx]

I doubt I'm even close to that. This gun is got a heavy hammer spring, reg at 150 with a plenum capable of 70-73 foot pounds for slugs. But I loosen the hammer spring for low power pesting around the property. Those big adjustments must be affecting performance, just figured the effect would be even from 250-150 bar.

Even though people treat the hammer spring adjuster like a speed controller and it appears to be successful, it’s a tune wrecker. Now you see why.

 

[elh0102]

I doubt I'm even close to that. This gun is got a heavy hammer spring, reg at 150 with a plenum capable of 70-73 foot pounds for slugs. But I loosen the hammer spring for low power pesting around the property. Those big adjustments must be affecting performance, just figured the effect would be even from 250-150 bar.

I'm not technically capable to tell you precisely what's going on with the reg, valve, and hammer spring, but I know that the tune is significantly unbalanced with the HST backed way off your normal higher power setting. My guess, if you back off the reg set point to achieve a working velocity at about 95% of maximum, you will see consistent performance. I assume that you do not see this anomaly at the higher power setting.

 

[Vetmx]

I'm not technically capable to tell you precisely what's going on with the reg, valve, and hammer spring, but I know that the tune is significantly unbalanced with the HST backed way off your normal higher power setting. My guess, if you back off the reg set point to achieve a working velocity at about 95% of maximum, you will see consistent performance. I assume that you do not see this anomaly at the higher power setting.

This is correct. What he is actually doing by backing his hammer strike off that drastically is turning his regulated gun into an unregulated gun. He now has a unregulated bell curve.

 

[Dairyboy]

I will say on my Taipans I haven't noticed this. At least on my Longs. They are tuned to more like 8% below but tune doesn't suffer. My Short is within the 3-5%. When I tune it down low for close range pesting I'm not worried about how the tune is. I can have a pretty large ES and still hit what I need within 20yds lol

 

[terry mc]

I know at least 5 guys who can answer this one. My 5 year old venerable vet 1 has this odd issue. When I fill to 230-250 bar, my shots are not as powerful. When the reg lowers towards 200 bar, the power increases, raising my POI. But from say, around 205 bar down to the reg pressure, shot strength is as consistent as you would expect. Is my reg getting worn/sloppy? It’s a huma, about 2-3 years old.

I may be missing something specific to Veterans, but if speed is varying with bottle pressure with higher bottle/cylinder pressure resulting in lower power.
As someone that shoots every time with a Chrono. I would suspect that plenum pressure is higher at higher bottle/cylinder pressure.
It sounds backwards but if your hammer strike is too light vs. your plenum pressure, higher pressure will close the valve quicker resulting in slower speeds.

As others have said use a chrono so you can track the actual speed. It takes some things like barrel harmonics out of the equation.

I have had the HUMA in my Crown do similar things with higher bottle pressure raising plenum pressure. As a result for benchrest shooting, I would only fill
to 210 bar max, to maintain maximum control over Extreme spread.


So yes, you probably have a regulator that is due for a rebuild or replacement.
Also for consideration is how close are you to maximum or minimum setting of your regulator, they are happiest and more consistent in the middle range of adjustment.

 

[MushroomPsyche]

I doubt I'm even close to that. This gun is got a heavy hammer spring, reg at 150 with a plenum capable of 70-73 foot pounds for slugs. But I loosen the hammer spring for low power pesting around the property. Those big adjustments must be affecting performance, just figured the effect would be even from 250-150 bar.

Yes, lowering the hammer spring tension that much will make many regulated guns follow a power curve like that. The opposite is also true in that too much hammer spring tension will have a regulated gun's power go down linearly as the fill pressure decreases.

Many people with Taipans use the hammer spring knob as a quick power adjuster but I just don't believe it's the intended purpose for that. It really is a tuner knob that should be set and left alone. From my experience, that adjuster is VERY sensitive and it is very difficult to return it exactly to where it was once moved. This is why I never touch mine once I have the gun tuned properly.