Canadian Airgun Forum

That's a nice picture of a very well made custom piston, very curious to know where you saw that. Hmm, I think I know: on the GTA, and this was made by a certain happymecanic, isn't it? https://www.gatewaytoairguns.org/GTA/in ... msg1485487 . Hmmm, same avatar as me, how funny. Look at reply #3 on this page: https://www.gatewaytoairguns.org/GTA/in ... c=174133.0

340-345 fps stock, 425 with this adjustable piston alone. I won't give all the details yet, but it's rather easily feasible to get more, I know that for a fact. It won't go over 500, but decent velocities CAN be obtained. Yes the pistol is rather ''smooth'' out-of-the-box, but it has the same power potential as the P17 and HW40.

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If everything's so lovely yeah, then why don't I, why don't I, why don't I, why don't I feel lovely?

Is the intake hole far enough back to function with the longer piston?

Hi airmec,

Do you plan to make more of this adjustable piston for the XP4? I am interested.

Thanks

通过我的 TAS-AL00 上的 Tapatalk发言

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AirArms TX200HC
AirArms S400F
Diana Outlaw
Feinwerkbau 300S
FX Dreamline Classic
Weihrauch HW100KT FSB
Weihrauch HW97KT
Weihrauch HW50S
Artemis M16
Artemis PP700
Weihrauch HW40
Beeman P17
Stoeger XP4

Wrong assumption....
PM happymechanic and ask him.....
I have done a raft load of piston extensions for 75/40/FAS etc...
My usual route is to bore out a counterbore on the front face of the piston which is approx 2mm deep x 17 mm dia. Then machining up a coin shaped disk which is a bit thicker than the counterbore is deep (0.5mm) with a drive fit and a drop of 638 for a simple fix but i have done more elaborate piston ext for people who wanted them.

Your 350 fps stock for this pistol is not in my experience, neither is 500 fps once tuned.
It may well be that you managed it with Valve mods but id hate to stress the mechanics to that extent to achieve it.
More realistically, i have routinely got 400 fps to 420 fps for these gun types.

My point here, was based on a number of disappointed shooters who have purchased these, and having stripped and rebuilt 2 that I just feel that the existing competition is a much better bet for shooters looking to buy an SSP.
The barrel is poor, the headspace too big without modification, resulting in less volume.
Build quality of case not as good as a bargain basement P17

Yes, but juuuust enough. Also I re-machined the head to remove the upper Oring groove, and shaved the head to get a 0.020'' thick ''lip''. This eliminated even more ''lost headspace'', but also got the Oring to not clear the breath hole. I had to elongate the hole a little after that.

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If everything's so lovely yeah, then why don't I, why don't I, why don't I, why don't I feel lovely?

I didn't planned to, but is there's demand I can and will make more.

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If everything's so lovely yeah, then why don't I, why don't I, why don't I, why don't I feel lovely?

Looks like you went same route as me.....Engineers usually do parallel technology.
Todd, he has just answered your question for you.
The intake is not compromised by all that bulk on the rear of the modded piston, it is of course just slightly compromised by the front face of the piston being a tad longer but in my case not enough to close it off.
Even if you had 1/2 of the hole closed off, it would still suck in the required air.

OK, PM sent here AND on the GTA .

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If everything's so lovely yeah, then why don't I, why don't I, why don't I, why don't I feel lovely?

Good, please post result of what he says.

Just log on the GTA and check your mail box.

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If everything's so lovely yeah, then why don't I, why don't I, why don't I, why don't I feel lovely?

Is not your single groove brass piston there, lacking the all important wiper, or is it just experimental.

Airmec and HappyMechanic is the same person FFS.

yes but that is not the question i am asking him.

Honestly you 2 should take your squabble to private. I think we are sick of it. You think you know, but you don't. You cannot accept that these guns can do over 400 FPS... They can, and we have. There are different ways to skin a cat, and both know how. You both have different ways of achieving the same goal. But to argue that these people are 2 different people is childish. I think he knows who he is.

How about being the better person and drop it?

We not really squabbling...you are ...
But it seems you often jump in on peoples posts with the same Troll values...
At least we bring experimentation and some technical advance instead of slagging people off..

Of course i know the poster you mention uses a different name on GTA but with same Avatar..ive been a member on there for 5 years!..heavily involved with the experimentation and sharing PM with Wyoman for about 2 years of that. Not using a different call sign...Check Clarky on GTA FAS 6004 post.
However, The poster you are referring, responded to my post reg the Stoeger having less potential volume and short on dead heading by 1/8” replied I was pretty much talking out my buttock as they are the same.
It was his post on GTA that stated it was smaller, and much less dead heading, agreeing with my own findings.

I dont want any arguments...its a waste of energy but i can play the game now and again...so i did here ....peace.