FX FX Impact heavy hammer, light spring

mubhaur

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Nov 8, 2015
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Karachi, Pakistan
Just want to discuss the effect of heavier hammer and lighter hammer spring in Impact.

It has free floating hammer, hence no double bounce causing wastage of air.

In order to control the dewel of valve, we can install heavy valve return spring and can also adjust the valve travel.

I understand that such set up would give smoother shot cycle without any compromise.

Lock time will increase a bit.

Opinions needed.

Bhaur
 
I installed the tungsten hammer weight in my M3 because I have my reg pressure at 150bar.
I did not install a lighter spring though.
The heavy hammer weight allowed me to back off the spring tension and still keep the same velocity of 980fps with a 40gr slug.
This made the rifle quieter from my shooting position on the rifle.
I have the tungsten hammer weight in both of my DRS rifles and it allows me to do the same thing.

The higher reg pressure closes the valve quicker than the valve return spring can.
This gives a short burst of high pressure air.

This is the way I prefer to have my rifles set up.
 
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In fact it happened to me when I was fixing an Impact mk2 without PP.

It had delrin guide inside the spring. I removed it and installed an OEM hammer weight. Now the hammer spring was proved to be too long. To the extent that hammer wheel became ineffective for changing fps in .22 18.13 grain JSB pellets.

Finally I removed a Coil or a bit more from the spring.

Now the gun has become so much comfortable to shoot that I couldn't expect it.

Shot cycle is great, no wastage of air and good accuracy.

I understand that we should reconsider the combination of hammer weight, hammer spring and valve return spring.

New combinations might give more pleasure.
 
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