[cockerpunk]

y0da900, on 18 April 2012 - 09:27 PM, said:

It's the baby powder that's stopping me. I'll try and remember to get some on the way home from work tomorrow. I'll run a test with 4 or 5 guns - both open and closed bolt of both poppets and spools. Removing the moment caused from the eccentrically loaded moving bolt during the poppet impact using a closed bolt poppet should be a pretty good indicator whether or not that or the airflow is the cause - also removes detents from the equation, which is easy enough to double check by single loading balls into an open bolt with detents removed.

if you could try 1 pc vs 2 pc too. interested in what happens in the tip of the barrel.

[Jack Wood]

cockerpunk, on 18 April 2012 - 08:45 AM, said:

ah, you are implying that the bolt itself rotates about the hammer/valve stem point which directs air at an angle .... mmmmm. so can you possible manipulate that with the fit and length of the bolt? that would be the test there.

so why then would we see bouncing on a gun like the AXE that lurker sees? that screams airflow to me, that the AXE volume near the poppet isn't enough, and it taps into the gas transfer tube in the frame, which gives it a pressure differential across the bolt face, and thus a bounce.

Actually the cup in the face of the boltdipping down pushes the ball to the bottom of the barrel prior to the pulse hitting the ball. The gas then exploits this positioning of the ball.

As to why you would see it in the Axe, well maybe the spring is causing a tipping actionas it compresses?

The detents don't have any effect on the ball being loaded into the barrel. Certainly our rubber finger detents do nothing at all compared to the loading and firing forces involved.

[y0da900]

Didn't get to do a whole lot of testing tonight, but so far I have gotten no consistent bounce or rub marks shot to shot in the back or tip when using a mechanical Matrix. I was shooting paint (and reballs) through a pipe kit - both the .683 back (which is closer to .681) and the .695 (which I have never checked with my bore gauge). Like others, I'm having difficulty getting a good coating of baby powder to stay reliably. I tried breathing through the barrel, putting some light air tool oil on a paper towel to swab it, and dry. I think next time I get a chance to try it, I will try a light misting of silicone lubricant spray.

[rntlee]

Just a question...at what point in trying to obtain a measurement does this method of testing become obtrusive to the proper action of the marker/barrel?