PCP Trying to learn pcp

[flyfisher]

I'm new to pcp rifles but not new to air rifles. I will have my first pcp rifle in a couple of days and trying to gather some info. can you tell me if i'm correct in this statement: A pcp rifle has a 3000psi air tank and is unregulated. The hammer spring is used to adjust the power setting up to the 3000psi
The same pcp rifle is regulated, the hammer spring also adjusts the power but only up to the regulated pressure.
Am I correct ?
One more question for now. I purchased and am waiting for delivery of the Barra 1100z unregulated gen1. If I have it set to a higher power and decide to lower the power, will the next shot be at that lower power ? Meaning that do I have to do anything else like degassing or something ?
Thanks, Bill

 

[Chief55]

It depends on the gun. Some are 3000psi, some 3,600, some 4,500 and one I know of is 5,000psi. Power or speed is set by the amount of air pressure used and the hammer spring is for fine tuning to get the best groups and shot string.

 

[Chief55]

With unregulated guns you will find that they shoot the best groups at lower pressure say 2,600psi rather than going to 3000psi. It is all about what speed the pellets like out of your gun. They are all different so it takes some playing with to find what works for you. Chronographs can be very helpful for finding the sweet spot for your gun and pellet combo.

 

[flyfisher]

With unregulated guns you will find that they shoot the best groups at lower pressure say 2,600psi rather than going to 3000psi. It is all about what speed the pellets like out of your gun. They are all different so it takes some playing with to find what works for you. Chronographs can be very helpful for finding the sweet spot for your gun and pellet combo.

Thank you for that info. Much appreciated. So the only way to adjust power is by increasing or decreasing the air pressure, Correct ? The reason I seem confused is because on a Diana Chaser co2 pistol one of the mods to increase power was to increase hammer spring length. Not arguing, just trying to understand.

 

[PapaT]

Thank you for that info. Much appreciated. So the only way to adjust power is by increasing or decreasing the air pressure, Correct ? The reason I seem confused is because on a Diana Chaser co2 pistol one of the mods to increase power was to increase hammer spring length. Not arguing, just trying to understand.

No. Hammer adjust will adjust your power. Changing how much you fill is more about consistent shots at power. Your shot curve will go up slightly, plateau for a bit, and then go down at parabolic rate (similar to co2).

 

[flyfisher]

No. Hammer adjust will adjust your power. Changing how much you fill is more about consistent shots at power. Your shot curve will go up slightly, plateau for a bit, and then go down at parabolic rate (similar to co2).

Thank you, that makes sense to me. It makes sense because a YouTube well known air gun reviewer did a review on the same 1100z that I ordered. The stated that with the hammer spring adjuster out flush with the housing the pellet would not have enough pressure for the pellet to leave the barrel and said that that position was a starting point.
For the second part of my original post, The rifle has a 3000psi tank on it, if I fill to 3000psi, can i adjust the hammer spring down and or up as desired with out damaging anything ?

 

[FL22]

I'm new to pcp rifles but not new to air rifles. I will have my first pcp rifle in a couple of days and trying to gather some info. can you tell me if i'm correct in this statement: A pcp rifle has a 3000psi air tank and is unregulated. The hammer spring is used to adjust the power setting up to the 3000psi
The same pcp rifle is regulated, the hammer spring also adjusts the power but only up to the regulated pressure.
Am I correct ?
One more question for now. I purchased and am waiting for delivery of the Barra 1100z unregulated gen1. If I have it set to a higher power and decide to lower the power, will the next shot be at that lower power ? Meaning that do I have to do anything else like degassing or something ?
Thanks, Bill

There is a wealth of information on HAM.

Bob’s Guide To Tuning Unregulated PCPs - Hard Air Magazine

Today, HAM’s Technical Editor, Bob Sterne talks more in detail about air rifles and gives the benefit of his experience in tuning unregulated PCPs.

hardairmagazine.com

 

[Danman]

Thank you, that makes sense to me. It makes sense because a YouTube well known air gun reviewer did a review on the same 1100z that I ordered. The stated that with the hammer spring adjuster out flush with the housing the pellet would not have enough pressure for the pellet to leave the barrel and said that that position was a starting point.
For the second part of my original post, The rifle has a 3000psi tank on it, if I fill to 3000psi, can i adjust the hammer spring down and or up as desired with out damaging anything ?

Another great resource is Matt Dubbers (AirArmshuntingSA) PCP series on YT. Breaks it all down, and helped me understand it when i was getting into PCPs.
As mentioned the fill pressure is often lower on unregulated guns as you will actually loose power with too much air pressure fighting the hammer spring when u pull that trigger.

 

[Chief55]

Yes, as mentioned, the hammer spring will change the power up or down, but the initial setting would be with the air pressure in the tank, then fine tune the speed up or down with the hammer spring for the best groups and or shot string with your pellets. It is best to start with a proven pellet brand in a standard weight. JSB Exact is a good pellet to start with in most brands of airguns. They just work.

 

[Jaabaa]

Bobs guide is good.
Your going to have a lot of fun with that rifle.
If anything a little trigger work, but not bad what I've seen on YouTube. Airgun Detective maybe?

 

[PasadenaMike]

When tuning a regulated airgun, your primary adjustment is the regulator pressure, but the hammer spring needs to be adjusted in harmony with it.

General Rule:
The higher the regulator pressure, the harder your hammer needs to hit to open the valve. However, if the hammer hits too hard, you’ll waste air.


Tuning Steps for Regulated Guns:

Set your regulator pressure.
Slowly increase the hammer spring tension until you reach the maximum velocity for that reg pressure.Back off slightly from peak velocity—some recommend reducing by 3–5%, others suggest dropping about 10–15 fps. This puts you in the “sweet spot” for efficiency and consistency.

For Non-Regulated Guns:

You’re looking for a pressure range where the velocity stays relatively consistent—often within a 20–30 fps spread (or whatever you’re comfortable with for your accuracy needs).

Example – Talon P:
It can operate from 3000 psi down to 1000 psi and give over 50 shots.
However, that wide range produces an extreme velocity spread of ~200 fps, which may be acceptable at 15 yards but will cause accuracy issues at longer distances.
The best performance comes between 2400–2000 psi, where I get 8 good, consistent shots with just a 25 fps spread.


Understanding Hammer Tuning:

. If your hammer spring is too strong, you’ll overshoot the peak velocity and enter a downward slope—wasting air and losing consistency.

• If it’s too weak, you’ll be on the upward slope, still climbing in velocity with each shot, which also causes inconsistency.
• The goal is to find that plateau in the velocity curve—the sweet spot—where shots are most consistent.

 

[PasadenaMike]

Welcome by the way. I only own the Talon p without a regular. It’s on low and it shoot average 891 fps with Hades.