My experience with new frame extender
So I bought some more black anodized tubing to make another frame extender to slip over the 24″ .25 barrel. I cut 18″ of it, went to my buddy’s who turned a alumi cap for me, just like for my other extenders. Pressed fit the cap in with long clamps, and off I went back home to check it out.
I’ve been shooting this gun from inside the house, it’s SO freakin loud that I think people can still hear it from outside, and all windows/doors are closed to keep the sound in, (except the window I’m shooting out of lol) With the vented front barrel bushing, the gun was so quiet with extender installed I was able to take it outside to shoot. I soon realized I couldn’t hit the broad side of a barn. One right in the bulls eye, the next 4″ LOW. The next 2″ HIGH, the next 3″ to the left, the next a bulls eye again. I couldn’t understand this, I was about ready to pull the hair out of my head, it was SO inconsistant. After doing this some more with no luck what so ever, I about gave up. Then I figured maybe it was the extender, so I took it off, went back inside and shot again without it… bingo… right back to nickel/dime size groups again. My other extenders have no such issues at all with shorter barrels in .22. All I know now is that I can’t shoot this gun in .25 until I get a extender shroud that works. Wondering if anyone knows why this extender makes the gun perform so poorly? Sorry so long.
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Take the end cap off and leave the shroud on. See what happens.
Or drill out the end cap even larger and see what happens.
😉
not intended as a be all end all solution, just a possibility i have encountered.
shrp, that still would not explain why his shots are all over the place. If that was the cause, they should all be affected the same by the air. I have made many shrouds for 24″ barrels, with no baffles, and accuracy was not effected.
what I have run across is the air behind the pellet is traveling at a much higher velocity than the pellet itself. With no baffles, I beleive the pellet exits the barrel, then the high pressure air, traveling faster, gets in front of the pellet and interferes with accuracy. With a baffled shroud, majority of the air is kept behind the pellet. a larger exit hole may help, at the expense of some sound control of course.
Saug,
If you are getting that whacky accuracy with a shroud on and it is OK when it is off then it is clipping.
Been there done that. More then once.
Believe me, I checked for clipping in the end cap hole… no signs of that what so ever. It’s a 5/16ths hole which should be appox 1/32nd clearance around the pellet. The tube is centered as good as can be, good tight fit… no slop at all. I’ll get it figured out somehow.
so you want a .30 hole drilled in the end
cheers
sam
.30″ – .25″ = .05″
😉
Half inch would be a bit large.
He wouldn’t have to worry about clipping any more. 😆 😉
so you want a .30 hole drilled in the end
cheers
sam
.30″ – .25″ = .05″
😉
Half inch would be a bit large.
when making shrouds/frame extenders always make the hole .5 bigger than the caliber.
so you want a .30 hole drilled in the end
cheers
sam
Saug,
You were clipping.
You need a bushing that is dead nuts accurate on the end of the barrel, it can should be vented and tight to the shroud. The end of the barrel needs to be perfectly lined up with the hole in the end cap. Also you might want to open the hole in the end cap just a bit to make room for that pellet.
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This has been my experience as well. The amount of energy expelled by a shot is so great that if anything within a LDC or baffle setup is even minutely out of tolerance, out of round or out of position, pellet flight will be affected. Quieting our airguns while keeping accuracy is art as well as science.
It is easy to tell if a pellet is clipping… and if it were then none of the pellets should hit bullseye. It comes down to the construction of the shroud.