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ZipSnipe · Veteran Member

Ok I recently just got a daisy 777. I couldn't find anyone that has done any mods to the gun. Specifically power, so I was looking at how the gun put together. Not happy about the valve molded on the barrel but I was looking at the pump head(piston that the lever pulls back to charge for air)

Anyway take a look at the pic , if I remove the red area of metal making the pump head concave therefore allowing more air to be charged I should get a boost in power?............Right?

I mean don't we need more volume ? I might open the valve ports a touch too

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rsterne · Moderator

The opposite would occur.... You would be increasing the headspace and therefore lowering the compression ratio.... The amount of air you are compressing depends on the swept volume of the pump (piston area times stroke).... The pressure you can raise that to depends on the compression ratio....

Flat Topped Pistons and valves sold for the 13XX series are all about eliminating the headspace in the hollow pump cup....

Bob

ZipSnipe · Veteran Member

Oh so to get more power out of my Daisy 777 we are talking about making a new side lever with an increased stroke which means I would need a new milled tube for it. Too much work :-(

rsterne · Moderator

Changing the lever would only work if it increased the stroke of the piston.... Then you would be moving more air per pump.... Of course that isn't the limiting factor anyway, as you can always pump more times (assuming there is a check valve in the gun).... eg. 3 pumps at 4 cu.in. instead of 4 pumps at 3 cu.in. ends up being the same thing....

Bob

ZipSnipe · Veteran Member

I think I will leave it as it is. Just replace the seals in it and call it the day.

Its a shame cuz it looks like a powerhouse but instead just a gentle breeze 10 meter gun but very accurate from what I read.