edge .177 low velocity

[rong1966]

I got my edge .177 in December 2015 and shot it regularly for 11 months until I bought a Benjamin Maximus.  The edge (vortex) is  the first and only springer I have ever shot  and it felt pretty powerful to me.  Sometime during the last month I was regularly using it I noticed that it sounded different; there was a metallic clang when it was shot.  I had replaced the piston seal approximately 500 shots prior to this.  I also noticed that an internal piece of the stock that contacts the trigger group broke off.  Anyway, I recently bought a chronograph and was surprised to see that my velocity numbers are low--7.9 gr benjamin hps shoot at 850 fps and 8.3 gr superdomes at 785 fps.  I checked the piston seal and it looked good; I put in the original seal and got the same numbers.  I checked the breech seal with the tissue test and it passed.  The guns cocks with the same effort as when new (as far as I can tell), so could I have gotten a weak or underfilled gas ram? Or could the gas ram have weakened over time?  I have over 3000 shots on the rifle.  I don't shoot the edge much now, but am just interested in what may be happening. 

[SteveP-52]

New piston seal and breech seal is fine leaves the gas ram and although I've never heard of one slowly leaking out, it's possible I guess. I knew when I bought mine that gas rams would be near impossible to get short of replacing with a Crosman NP ram so my plan was always to just get the spring, top hat and spring guide from Hatsan and convert mine to springers as they're not hard at all to rebuild.
I have Edge .25's in both spring and gas ram and the spring version actually shoots faster than the gas ram does.

On a side note, if you have a Hatsan fill probe and a hand pump, the Vortex rams can be filled, just don't go too much past the recommended 125 bar, I know from experience...lol

[rong1966]

From what I've read the gas rams usually fail completely which leads me to believe that mine was weak from the start.  Thanks for the reply.

[SteveP-52]

I've read all the same stuff, they shoot fine one day and the next nothing, no power at all which made me wonder as yours still has power. The ram stays centered in the receiver with nothing more than a plastic nub on the end cap and I've always wondered on mine what was going to happen when that plastic wore out from regular shooting and the ram was no longer centered. Might be the metallic clang you heard if the end of the ram is just bouncing around in there and you might not need anything more than just a new end cap to get the piston re-centered.

[Mr. Panther]

I had a Titan GP that did the same thing after I changed it out to a .177, made that metallic sound. I started shooting a heaver pellet in it and it seemed to go away. I changed it back to a .22 and never had that sound come back. It could be a switch of pellets could help, just a suggestion, as they might seal better allowing for the piston to have a bit of cushion at the end of the cycle. It worked for me.