I have now been shooting Air Arms PCPs for close to 20 years, shooting tens of thousands of .177, .22, and .25 rounds.
While I am certain my next rifle will be a really high-tech, regulated model, (I really think I want a Red Wolf), and while I have chronographed thousands of pellets and documented the power curve, I have never really studied where the POI actually begins to fall off. Today, I learned that even though the fps falls off rather dramatically after several shots, the POI doesn't change as much as one would think.
Within my 18 yards controlled indoor range environment, I shot all three of my S-510s today, starting at exactly 200 bar, monitoring their statistical performance on the chronograph, while watching the impact on the POI. Even though one would expect the POI (elevation) to drop after losing even 20% of the velocity, it wasn't noticeable until each of the rifles lost about 50 bar of the 200 bar initial charge.
For the .177 shooting a JSB 10.34 Gr pellet, it shot nearly one hole groups until I had gone through about 80 pellets (at full power), within a range of 1030 to 960 fps. Even then, the trajectory might have faded 1/8" to 3/16" of an inch.
For the .22, shooting the JSB 18.13 Gr pellet, it was about 50 pellets before an elevation drop began to be noticeable.
For the 25, shooting the JSB King Heavy 33.95, I still got to 40 pellets before even a slight drop off in POI could be seen on the target.
The only thing this exercise told me was that while there is no doubt as to the sound nature of the regulated theory, I don't think it is as big of a deal as we would all like to make it or believe it to be. So don't be in a hurry to ditch your trusty non-regulated gun thinking that you are going to receive some magical result on your next hunting outing where at the most only 10 to 20 shots will be consumed. My tests indicate that the difference is so negligible that you will never notice any real difference.
While I am certain my next rifle will be a really high-tech, regulated model, (I really think I want a Red Wolf), and while I have chronographed thousands of pellets and documented the power curve, I have never really studied where the POI actually begins to fall off. Today, I learned that even though the fps falls off rather dramatically after several shots, the POI doesn't change as much as one would think.
Within my 18 yards controlled indoor range environment, I shot all three of my S-510s today, starting at exactly 200 bar, monitoring their statistical performance on the chronograph, while watching the impact on the POI. Even though one would expect the POI (elevation) to drop after losing even 20% of the velocity, it wasn't noticeable until each of the rifles lost about 50 bar of the 200 bar initial charge.
For the .177 shooting a JSB 10.34 Gr pellet, it shot nearly one hole groups until I had gone through about 80 pellets (at full power), within a range of 1030 to 960 fps. Even then, the trajectory might have faded 1/8" to 3/16" of an inch.
For the .22, shooting the JSB 18.13 Gr pellet, it was about 50 pellets before an elevation drop began to be noticeable.
For the 25, shooting the JSB King Heavy 33.95, I still got to 40 pellets before even a slight drop off in POI could be seen on the target.
The only thing this exercise told me was that while there is no doubt as to the sound nature of the regulated theory, I don't think it is as big of a deal as we would all like to make it or believe it to be. So don't be in a hurry to ditch your trusty non-regulated gun thinking that you are going to receive some magical result on your next hunting outing where at the most only 10 to 20 shots will be consumed. My tests indicate that the difference is so negligible that you will never notice any real difference.
