Awesome, very well explained, Lloyd! Thank you for taking the time to detail it all out for us.
Thank you Matthew. It can be almost impossible to figure out what happened during incidents like this, because it is all over before you even knew it started. One time at work (more than a couple of years ago, LOL) we were testing an electrical cabinet on a MIL-901D light weight shock machine. Light weight for the USN means a 400 pound hammer on a 5 foot long handle, swinging down by gravity and striking the heavy hull simulation plate that the equipment was mounted to. The equipment worked fine before the hit, but not afterwards. Hmmmmm. Failure investigation found a relay on the deck outside the fully latched equipment, and everyone knew that the relay had to have been in the cabinet before the hit. Puzzling. But the high speed camera told the story. During the hit, the equipment door over-road its latches and flung open, the relay flew out of the cabinet, and the door slammed back shut and re-latched itself. If the camera hadn't caught it, everyone would have swore that it was impossible because no one could see it happening. You just never know.Lloyd
Original hipac that I hydro tested has fine threads only and a hex machined into the end. od of the oring groove is .700" x id of tube .604" ( .052" wall)Second tube (purchased second hand) has the hex and coarser threads. od of the oring groove is .688" x tube id of .613" (.0375" wall)Third tube was purchased new. Coarse threads and no hex. od of the oring groove is .682" x tube id of .615" (.033" wall)
Sequence of Events1) During one of the most recent air fill-ups of the gun in question, I believe that the single 8-32 screw securing the Disco valve in the tube started to bend and shear off. The valve started to move toward the back of the tube, but was stopped when the groove in its O.D. bumped into the stock/trigger screw that protruded inside the tube.2) At this point, the valve was being retained by a partially failed 8-32 pan head screw, and the single trigger/stock screw. Because the movement in the valve had been so slight, the failure was not obvious.3) Disassembly started. The bands and the barrel/breech assy were removed, along with the rear cap and hammer. No problems at this point.4) The gun was turned over and held, in some fashion, and the trigger/stock screw was unscrewed. At this point, the single 8-32 valve retention screw finished shearing off, and the valve was launched out the rear of the tube. Because the valve was snagging and shearing, it did not leave the rear of the tube in a smooth, coaxial fashion. Instead, its movement was irregular and imparted both axial and lateral reactions in the remaining, hand-held, tube and HiPac assy. Assuming only 1,500 psi of air in the gun at this time, the valve was launched at close to 400fps with over 200fpe.5) The reaction of the remaining hand-held tube and HiPac assy was also the same 200fpe, but much slower because of the heavier weight (equal and opposite reaction), maybe about 60mph (changing units to help us visualize).6) The tube and HiPac assy flies out of the hand, but because of the way it was gripped, and the offset nature of the force from the valve, the tube doesn’t go exactly straight but instead some of the energy starts to flip the tube like a boomerang. Visualize muzzle flip in a pistol, or slinging a stick across the yard. 7) The moving and spinning 22xx tube and HiPac adapter and HiPac tube impacts something, maybe a table, or wall or appliance. Maybe it has only spun an eight of a turn, but its impact is angular, and no matter how slight the angle, the HiPac adapter snaps at its weak point where the o-ring groove is. Think of holding the back end of the tube and whacking it at 60mph against the surface of a table. A solid tube would stand up fine, but there is a weak point in this assy.8] Finally, the three parts: the valve, the 22xxr tube, and the front HiPac tube, all end up in different places.Lloyd Sikes
I have had mine for a few years and have never filled past 1800. I love mine. I am also not stupid and would never treat it like dude did. I CERTAINLY wouldn't be careless enough to take it apart with air in it. The hi-pac is safe and operates as advertised. If you want to "MOD" everything insight and act carelessly, please don't fault somebody else for something you did. Own your mistake and man up. I guess I have another related comment. If you have a low power airgun and want to "mod" it into a high power airgun, just get a higher power airgun. Tweaking and tuning aside... I know it's fun but leave the heavy lifting to the trained and talented. The basterdized POS this guy had was an accident waiting to happen and it's a terrible blemish on our community. Learn from it and if nothing else... use your head, de-gas your stuff before you even touch any tools. I glad dude didn't get seriously hurt or killed but he did that to himself. Nobody is to blame but him. End rant.
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