Chrony experiment, volunteers needed

[mr007s]

I am interested to learn if the speed in which the trigger is pulled has any effect on velocity with air guns. Those of you with access to a chrony are invited to assist in this experiment. If you are willing to participate do the following.

A-Fire a 10 shot string, alternating with a gentle, slow as possible trigger pul,l and a quick as you can jerk on the trigger.  Lets say odd number=easy, even number =fast
B-Review your findings and post the results here
C-If you notice a trend develop between the two trigger operations I want to here your theory as to  what was going on inside the gun , especially the hammer and spring.



Maybe we will see no difference, maybe we will. Should be interesting anyway, and fun!

[eric]

i'm game but until i get some good weather with free time i can't do much

[1377x]

ill try it
my 357 should be perfect for this when i get it back this weekend i should have some numbers weather permitting

[mr007s]

I had time today, after all the eggs were hidden and found, to run some test. It was a pretty Easter with temps in the 80's here in NC. I used three guns, two CO2,s and a 1377 pumper. Here are some charts for you to study. I haven't taken time to do that as I have venison steaks going on the grill and that takes precedent.

[mr007s]

Here is the third chart. It does look as though the easy pull yields a slightly slower speed but there are probably many factors to weigh before any conclusions can be drawn. I believe how deeply the piercing pin penetrates  the cart would have a bearing on this to an extent also. Anyone have thoughts or experience with tinkering with the pin. I believe Darth or North star may have some knowledge about that.

[quickster47 †]

I think Darth believed he was having serious issues with his piercing pin and even went to the extent of reshaping it.  But in the end I also believe he dismissed the idea that the pin was a problem.

Carl

[bdb12586]

I shortened my pin by about 1/8" and reshaped it. I don't have a chrony but in conjunction with a lighter valve spring it makes a much bigger hole than original so that means the valve is opening more, at least the amount removed from pin. I'm still getting 25 to 30 decent shots per co2. Darth made a comment in his post not to shorten the pin he would explain later, but i never saw the explanation. I have no ill effects other that it takes 4 or five shots to now puncture cartridge

[Darth]

Well, I did reshape my pin ( to 30 degrees) even though I really didn’t make a big deal of it here because I felt it didn’t make much of a difference in the overall scheme of things. I actually have a “four sided” pin. And I did shorten it by .030”. This didn’t seem to change anything from the stand point of velocity.

From my testing in my “heated cooler” … I’m sure I pulled the trigger FAST and SLOW and my velocity numbers were always about the same. I would think that "once the hammer falls" it would travel at about the same speed yielding the same blow to the valve. But I also have all those surfaces polished.

Darth made a comment in his post not to shorten the pin he would explain later, but i never saw the explanation. I have no ill effects other that it takes 4 or five shots to now puncture cartridge

This was my piercing pin response ... it's kinda messed up from the "hacker attack" I also noticed that my BOSS valve has a "longer piercing pin travel" as well.
http://www.crosman-air-pistol-owners-forum.com/board/index.php?topic=2981.msg27533#new

Darth