Huma Regulator Recovery Time

I discovered something very interesting with my Brocock Bantam Sniper HR today, gun is more accurate if you wait a little longer between each shot. If you shoot gun say within 5 seconds or less alter taking a shot you will get flyers both high, low left and right. After cycling bolt I counted to 10 between each shot and gun groups are much tighter with JSB 16 gr Exacts and Crosman Premier 14.3.Try this once with your Huma Regulated PCP and see what happens.
 
it is possible your regulator is gummy. I just experienced this with my Ataman Ap16 (not a huma reg in there that i know of) either way, it started wanting longer recovery time between shots (to the point it was also acting like it was out of air when the tank was only half empty and seeping air. when it did that, i would cock the gun, wait 10-15 seconds and then i would get a shot), sent it in for warrenty work. All they did was lube up the regulator and its back to good as new. Not saying its the same thing, but with that experience i learned that regulators can act up and may need some service.

the head gunsmith at Air venturie told me to put one or two drops of pell gun oil in the regulator or air chamber (very infrequently, with regular use i think it was only a couple times a year) to keep the regulator in fine form. 


 
My gun for the most part is almost brand new, regulator should not be gummed up but could be defective from the factory. I shot two test targets for comparison, I will post both later today and you will see what I'm talking about. I will call AoA and ask them for a new regulator, gun comes with 3 year warranty. I waited ten full seconds between shots just as a test, may not be quite that bad, however gun cannot be fired accurately in rapid succession.This gun has been like this since I took out of the box new. When you shoot needle drops off and is slow to rise back up to set pressure and you can hear air pressure building before stopping. The good new is the rifle is extremely accurate so I know barrel and everything else is ok. I have in the past purchased new PCP's with accuracy issues and it's either something loose, a bad barrel or clipping if all pellets are inaccurate.
 
I like the instrumented approach. I have a Huma regulator in a .25 Marauder. When fired across the Chrony, shots which were fired within 5 or 6 seconds of the previous shot were slower than shots I waited a longer period of time to fire. The gauge represented actual plenum pressure. The last hundred pounds of plenum pressure took longer than the first 1700 pounds (which was nearly instantaneous). 
 
My gun for the most part is almost brand new, regulator should not be gummed up but could be defective from the factory.

-should not be- my ataman ap16 was brand new, but had this issue arise after about 500 shots (i was shooting alot that first week or two) i would not be suprised if its something sticky in there, or if its been that way from day one like you say, maybe a weak spring
 
From the installation instructions for a Huma regulator, 

"You receive your regulator in a small plastic bag. The bag contains the regulator and also a tiny M3
allen flow restrictor bolt that has to be placed inside the adjustment screw. This bolt creates a slower
but more accurate regulating behavior."

"Tip; You can also grind one side of the screw a bit for a quicker response time of the regulator"

"When you are testing/adjusting your rifle using a chronograph, please remember to take sufficient
time between the shots for the regulator to recharge the regulated chamber volume."

In other words, this is normal behavior.