The stock piston is APS2, but not 90 degrees like I understand the rest are. Thus, the piston is a custom 45 degree piston, designed to fit in the APS2 cylinder. The only successful changeouts I'm aware of were APS2 pistons that were shaved down to 45 degrees.
The stock piston and trigger unit have had no problems with two SP170 springs for over several months now, and a 500fps (supposedly) spring before that. Upgrading this is irrelevant at this point, given that two SP170 springs have proven incapable of bringing the power up.
The issue is that the gun does not produce more than 2J of energy, despite improvents to every area that would impact this. I realize that since the gun is APS2 spec cylinder, shortening the barrel to 430mm from 465mm probably lost me some power, but surely full seal and a beefy spring would substantially offset this? Apparently not.
Previously, the stock oring was insufficient to prevent leak by with my original SP170. With the new oring (Same size best I can tell) the piston is pretty snug. I wouldn't say it is hard to move but it does give full seal like it is supposed to.
The only other thing I can figure is that the cylinder head has not been aligned with the barrel correctly, which caused me to think my previous barrel was bent (it was, but the new one has the same problem)*. I'm going to rectify that, play a game or two with it, and maybe after that toy with piston weights until I purchase a SSG96 or SSG10A2.
As it stands, the gun's stock performance at $80 makes for a great starter gun, but despite dropping $170 into it at this point it shoots only marginally better than it did before. Why I cannot get the energy higher than 2J is beyond me, but from what I've seen nobody else has managed this either.
*Maybe that's not entirely true. I put a second o-ring in a extra groove for testing purposes. It may be causing extra drag. Still, aren't 170s supposed to give 3.3J min? Surely that's not causing a full joule to be lost, especially since this was not an issue previously
The stock piston and trigger unit have had no problems with two SP170 springs for over several months now, and a 500fps (supposedly) spring before that. Upgrading this is irrelevant at this point, given that two SP170 springs have proven incapable of bringing the power up.
The issue is that the gun does not produce more than 2J of energy, despite improvents to every area that would impact this. I realize that since the gun is APS2 spec cylinder, shortening the barrel to 430mm from 465mm probably lost me some power, but surely full seal and a beefy spring would substantially offset this? Apparently not.
Previously, the stock oring was insufficient to prevent leak by with my original SP170. With the new oring (Same size best I can tell) the piston is pretty snug. I wouldn't say it is hard to move but it does give full seal like it is supposed to.
The only other thing I can figure is that the cylinder head has not been aligned with the barrel correctly, which caused me to think my previous barrel was bent (it was, but the new one has the same problem)*. I'm going to rectify that, play a game or two with it, and maybe after that toy with piston weights until I purchase a SSG96 or SSG10A2.
As it stands, the gun's stock performance at $80 makes for a great starter gun, but despite dropping $170 into it at this point it shoots only marginally better than it did before. Why I cannot get the energy higher than 2J is beyond me, but from what I've seen nobody else has managed this either.
*Maybe that's not entirely true. I put a second o-ring in a extra groove for testing purposes. It may be causing extra drag. Still, aren't 170s supposed to give 3.3J min? Surely that's not causing a full joule to be lost, especially since this was not an issue previously