Wondering.......why do you want to "rough up"........
June 11 2012, 9:51 AM
your compression tube?
I've READ that the receiver need grooves to hold the lube, but it also SEEMS to me that such grooves will also "pump" lube into the compression chamber increasing the "dieseling effect" on velocity, therefore the volume of available "pumped lube" due to the number of shots, temperature etc would affect the velocity/poi....or so I would IMAGINE.
Recently I went with only dry graphite powder as a piston seal lube (I'm running oring seals) and noticed perhaps a 10fps velocity drop vs molly paste lubing, however the shot consistency with graphite lube SEEMS better. I'm assuming this is due to less "oil vapor burning", especially as the temperature changes during the day.
Seems that there is a lot of piston gun advice that gets printed on the forums, then this "info from the gods" gets passed around as being "holy writ" without actual testing, but I'm wondering is anyone had actually done a mirror-vs-honed tube comparison as it pertains to shot CONSISTENCY and ACCURACY instead of velocity.
IMHO, if such honing doesn't actually improve PELLET ACCURACY.......well......what's the point? Perhaps honing does inmprove velocity in some guns, I don't know, it's just that I haven't noticed such a phenomenon with my HW springers, and for my PERSONAL oring sealed guns I actually "polish" the tube with oiled 600 grit wet-or-dry and things seem to work well that way.
the old cardew books, who didn't deal with accuracy, but on efficiency. They contend that minor deiseling is what gives a bit of a power boost to most springers, burning minute amounts of oil on each shot. Too much, of course, what we normally call dieseling.
On the lower power spring guns of the time, leather seals squeegeed the oil to be compressed, hence a 'mirror finish', while synthetic seals used tiny scratches in the cylinder wall to pick up oil in front of the sea.
So, on a higher power gun like that one, I don't really understand the thinking behind roughing it up either, as you can increase the dieseling just by using more or different lubricants. But, if you really want to, just get a hone at your auto parts store, as coarse as they have, chuck it into your drill, and hone away. Or, the coarse emerycloth with one end taped on a dowel, so the other end flaps the tube, again chuck it up and spin it.
Sometimes you find a cylinder with a substantial gouge in it, and you have to use the sandpaper method to smooth it out. Otherwise it may cut up your seal. But that is only to try to fix a problem thats already there.