Woe is me! I need a little help guys

[fz1yamaha]

Actually I had same issue,When I snugged the shroud up under load with both barrels ,make sure the shroud collar is not rolling/cocking when you snug it.of coarse you have barrel band not touching during rotation of shroud?What I did was thicker o-ring between collar and breech,then i rolled an o-ring down the barrel over the collar and its o-ring up against breech ,then shroud screws on pushes last o-ring out of way ,pinching shroud tightly with o-ring and air tube,snug it up,and back off 1/4 turn, nothing has moved or changed on poi shift in couple months,was even thinking of small piece of heat shrink where shroud and barrel band meet.just alittle more isolation and less lateral torque, load,can be applied from rough handling,seemed to of work for me,I actually indexed barrel with breech off air tube using a mag as a spacer,for good alignment Good luck sounds like your winning alittle at a time,

 

[JimNM]

I counted up the pellets that I have shot over the chrony and into the backstop - and I am over 3k at this point. I have been shooting more than I had thought and the stock barrel was in need of a cleaning as is was now acting funny, too.. While I was giving it the the old Goo Gone treatment, I took the fancy barrel out and cleaned it with a vengeance, too. There was nowhere as much gunk in the aftermarket barrel, but there was some... (light bulb #1)

I took my time and gave it a good thinking. I put the fancy barrel on, and the LDC. Shot a few - and the pellets were nearly out of the scope FOV at 30 yards. (Light bulb #2) Hmmm, I yanked the LDC off - and what do you know? I was only about 1 dot each up and right from POA and for as much as I have been chasing POI, that was very welcome. For now, I am shooting the aftermarket barrel w/o the LDC. I am seeing some light at the end of the barrel. While not as tight of group as I want, I am seeing three of eight pellets in the same hole using sub optimal pellets.

I am not the happiest that the LDC is causing problems - as I really like the phhhft! sound rather than the pop! sound, and I don't want to waste the cash that I laid out for the LDC - but right now I want to have the accuracy back. It's getting there.

Thanks to all who have made suggestions

 

[JimNM]

Thanks guys for the help. I slowed way down on the Prod for a month or so and perused other hobbies. This weekend I tore back into the gun after spending a few night shifts with my nose burried in the web pages.

What I found was.... The air stripper on the stock barrel does come off (!) and it is needed on the MM barrel. Well duh. My malfunction, not the after market barrel.

I did not read the directions and I missed that crucial point. My groups improved immediately, and were fantastic considering I was shooting on no sleep and beaucoup caffeine. I measured a magazine group of pellets under a dime size and 7 of those 8 into two holes from my 30 yard rest.

s.http://www.rcgroups.com/forums/attachmentNew.php?attachmentid=9894063

​Thanks again for the tuning advice on the HS and HT

 

[NMshooter]

Sound like you are on your way. These rifles can be like old sports car. They definitely need tweaking. Hope to start refining my .25 now that I have completed a few projects myself!