Tuning Crown MKI 22 with a 380mm superlight barrel assembly question

[pesty3782]

MKI Crown with the new 380mm barrel in 22 cal....I just changed out the reg to Huma and got this fantastic shot string after going from Max down to 2 and A-C on the hammer spring knob. .Reg at 140 and shooting JSB 18's........This shot string is at 5 and the "Power adjuster" set at 25-30 (High) I was going to move the power adjuster to 22-177 (MED), but the wheel wont turn....Any idea if it is because I have the "Newer" barrel assembly on it? My MKII the Power adjuster moves with no issues. This was an older used rifle when I got it and never moved the Power adjuster because it was a 25 before the FX reg started to fail.

Thanks for the help and I plan and seeing how this tune shoots on Monday

Shot count: 10
Low: 923
Hi: 928
Avg: 926
Spread: 5
STD Dev: 2.3
928
926
928
928
928
923
923
928
926


Tony P.

 

[pesty3782]

Well I took it apart and super dirty so I cleaned it all up and now works, but stiff. Need to check out speeds at medium next.

Tony P

 

[jps2486]

That’s a great shot string. I suspect the O rings have become stiff and brittle with age, that’s why the wheel won’t turn. You might try warming up the area with a heat gun first. NOT HOT, JUST WARM! Take the barrel out first. Also, you might want to get some new O rings before fiddling with this. I really like my MK2 with the 380 mm barrel.

 

[davit66]

pesty3782, I had the same issue with my Crown MKII and the new .22 / 380 superlite barrel with the 'P' and 'S' flow ports. When the barrel is installed using the 'P' port (in the down position) I can't turn the Power Wheel. However, when the barrel is removed from the receiver, the Power Wheel can be turned to the different positions. If the barrel is installed with the 'S' port in the active position, the Power Wheel will also turn freely. I found the body of the power adjuster interferes with the barrel due to the small diameter of the 'P' port.
I have a .22 / 700mm barrel with the P and S ports but they are much larger openings and the Power Wheel is able to turn freely with this barrel.

The photo shows the size difference between the P ports on the two barrels. The port on the 700mm barrel is elongated and provides more clearance for the power wheel barrel when turning from one position to the next.
So long story short, I only use the S port on my 380mm barrel so I can always the different settings on the Power Wheel. Hope this helps.

 

[Mr12PM]

pesty3782, I had the same issue with my Crown MKII and the new .22 / 380 superlite barrel with the 'P' and 'S' flow ports. When the barrel is installed using the 'P' port (in the down position) I can't turn the Power Wheel. However, when the barrel is removed from the receiver, the Power Wheel can be turned to the different positions. If the barrel is installed with the 'S' port in the active position, the Power Wheel will also turn freely. I found the body of the power adjuster interferes with the barrel due to the small diameter of the 'P' port.
I have a .22 / 700mm barrel with the P and S ports but they are much larger openings and the Power Wheel is able to turn freely with this barrel.

View attachment 280748

The photo shows the size difference between the P ports on the two barrels. The port on the 700mm barrel is elongated and provides more clearance for the power wheel barrel when turning from one position to the next.
So long story short, I only use the S port on my 380mm barrel so I can always the different settings on the Power Wheel. Hope this helps.

Interesting. I haven’t checked the size of the ports on the 700. I will. If they are larger, I’ll swap them around. I only use the 380 because It’s a pain in the rear to take off the 700 every time I’m done so it can fit in the case.