The Unofficial P64 Resource Forum

A tech question, if you will.

I was thinking about simple blowback operation, and how most everybody here has switched their recoil springs to something heavier. Blowback is Newton's 3rd Law in beautiful action. Putting a heavier spring on your gun means more energy can be expended on pushing the bullet out instead of extracting the cartridge, right? So do you get higher fps with a heavier recoil spring? Or has my limited recollection of high school physics (taught by my dad, poor man, I never did understand why physics was so interesting until recently...) completely failed me?

I am tempted to say that is correct; however, I am not a scientist.

It seems to me the change in speed would have to be very small. People adjust for a lot of things effecting accuracy (changes in distance between targets, wind speed and direction, elevation…).

Recently I have been doing some reading on reloading. A lot of the people involved in shooting competitions do reloading so their bullets are consistent and predictable as possible. My guess is the difference you are talking about is even smaller than the variances the competitors are combating between reloading and factory loads. And the change would happen at the time of the replacement and then things would be constant afterword. You could adjust your shooting to that difference if it is even noticeable.

It could be interesting to see the replies you get on this subject. I will check in later to see them.

in theory your correct, but id have to agree with robalan that it would be minimal

im sure some one here has a formula that will prove or disprove this.......

I would have to say that the bullet would have already left the barrel before much recoil spring action is going on. The bullet is unobstructed and the slide travel in the opposite direction is buffered by the spring. The bodies in motion are not equal in mass or number. That's my two cents for what it is worth.