RAR 22 lr hitting low

[Mobuck]

Question from Tom's 4-H Shooting Sports group. I'm sure my response was on track but he wants me to ask the forum's opinions.
One of the kids is using a youth model RAR with a fiber optic front sight and the POI is still low with the rear sight adjusted as far up as it's limit.
First, is the fiber optic a factory standard? I don't know but mine didn't come that way IIRC.
Second, what are the options for either a lower front sight or a rear open sight with additional height?

 

[steelshooterco]

If you look at the Ruger catalog you'll see the standard compact one comes with a front fiber optic sight.

http://www.ruger-firearms.com/products/americanRimfireCompact/models.html

I'd suggest they return the rifle to Ruger, as there is definitely a problem with it.

You could scroll thru the models there and see if a different rear sight was added, that's a possibility too.

With the exception of model 8328, the rear sight looks like it is dovetailed into the barrel, so if it is off that bad, it could be the dovetail was cut too deep, or they used the wrong rear sight. Reason to return to factory.

 

[JFB]

How about taking calipers, take some measurements and see if the Line of Sight and expected Center of Bore are at a good angle, say 10 to 15 MOA

(not sure of this graph's ammo, just first I found in my photobucket

 

[Mobuck]

May be other factors involved. The rear sight blade has two wee little screws that allow it to slide up/down or be flipped from square notch to round notch. It seems the shooter's parental unit persists in his idea that the square notch is proper for target use with the fiber optic front bead.
Since neither Tom nor I have access to the rifle and can only make suggestions(I'm not even allowed on the range), I doubt that anything less than actually returning the rifle to Ruger will help. Tom was going to attempt to get the Dad to contact Ruger about a taller sight slider.
It's frustrating to see the kids struggle with equipment or attitudes that doom them to mediocrity or outright failure from the start.
I know how these things work but can't help. Heck, I was competing on a military rifle team when some of these kids' Granddads were in diapers.

 

[JFB]

do you know (will the parent provide);

how low
what range
sight radius

thus be able to better guess how much taller is needed

 

[Mobuck]

The kids are shooting 10 meters AFAIK. I think Tom commented it was 1/2-3/4" low so about the bottom of the bull. The sight radius on a 16" RAR is around 12".
Since the rifle wasn't zero'd from a rest with a specific ammo, I really can't determine the primary problem but the end result is most hits are below(off) the bullseye. My initial response was a suggestion to file that darned light stick off leaving a clean topped post but of course, that's not going to happen.
As I said, I didn't take the $250(plus 400 miles travel and two nights motel expense) "safety class" to become a "certified instructor", so I'm not allowed on the range. It seems that far too much of the practice sessions is spent addressing equipment issues or trying to compensate for ill suited firearms.

 

[JFB]

10 meters is 394 inches
1/394 is about 9 moa

x/16 = 1/394

only about 0.040" change at the sights is needed

a check of a 1022 rear blade was about 0.080" total adjustment.