I have an aa 500 in 177 completly stock.starting at 3 bars it has a 200 fps power curve from 820 to 1020 back to 820 at around 50 shots. do you think i need a new hammer spring.i don't want to install a reg at this time.thanks for your suggestions.
the pressure should have said 200 bar"spinj"Please clarify if you meant to state 300 BAR and not 3 BAR. Also, at what pressure was the rifle at when it dropped back to 820 FPS after the climb and what power level? (low, medium, high?) If you did mean 300 BAR, The S400 is not designed to operate at that pressure level as the hammer and valve spring tension is not mated to that kind of pressure. That is why you have such a sharp rise in velocity.
it is a s500 extra fac super lite"AirgunBill"I see that you say it is the AA 500 though I see there are more than one version of that rifle. Which one do you have and what fill level in bar or psi do they recommend. Bill
I got the gun from a good friend,it's about 2 years old.the gun had not been shot very much before i got it.i was testing with crosman 7.4"John_in_Ma"Did you buy the gun new or used? In .177 you should be getting 880fps with 10.3gr pellets with the power wheel a bit past half way. Your string should look something like this. http://airgunnation.dev/topic/shot-string-from-my-aa-s500-extra-fac/
If not then there certainly is something going on.
I will try to do so in the next couple of days"Jlands"Can you post the whole string so we can rule out valve lock?
The 7.4's point to why the speed was so varied. what. Was the gun stored with full pressure? I ask because the valve poppet can, but not always deform over time when stored under full pressure, causing inconsistent seating from shot to shot. Also I've tested crosman pellets in mine, just the domes not wadcutter, but they varied greatly in shot to shot consistency over the chrony and in grouping. I believe it has something to do with the hardness of the pellets and their oversized heads. Anyways i think with your new spring and a better pellet, JSB or AA you will find no faults with the rifle."r1d2"
I got the gun from a good friend,it's about 2 years old.the gun had not been shot very much before i got it.i was testing with crosman 7.4"John_in_Ma"Did you buy the gun new or used? In .177 you should be getting 880fps with 10.3gr pellets with the power wheel a bit past half way. Your string should look something like this. http://airgunnation.dev/topic/shot-string-from-my-aa-s500-extra-fac/
If not then there certainly is something going on.
Shot a 40 shot string using the cardboard box crosman 10.2 domed pellet,started at 200 bar and ended with a little over 150 bar.894,886,882,900,919,896,913,910,908,902,908,909,920,912,923,928,918,925,934,932,927,935,926,936,935,947,941,939,941,953,940,957,966,956,960,970,960,967,968.didn't have time to shot anymore.hope this enough info,so what do you think."Jlands"Can you post the whole string so we can rule out valve lock?