Quote Originally Posted by mrgeoff View Post
So, I fitted an Altaros regulator to my S400 (very old, pre-anti tamper)

I put it across the chrony, from 160 bar down. As expected, the fps was fairly consistant, but dropped ever so slightly from the start, down to the regulator set point, and then dropped faster below the reg set point. All good, just on fps variations. From 160 bar to 125 bar, it dropped about 10fps.

Unfortunately, this has not translated into great 25m benchrest results.... So I zero in at 160 bar (my bottle is a bit empty) great, first 5 shots perfect. Then the POI starts to climb, and climb, so after 20 shots I re-set the zero down 2 clicks. Its spot on again, until it comes off the reg, and drops as expected. So I re-fill and the POI is low again!

So I dont understand, why does the POI climb, as the fps slightly decreases on the regulator?


Thanks!
As the FPS drops the trajectory becomes more curvy and hence the rise in the POI. With a faster pellet trajectory is more flat. What is interesting is the amount of shift in POI which seems to be significant. Which version of the Altaros do you have if I may ask? These are are also set to 120 bar from the factory which is slightly too high for our pedestrian guns.

A.G