Need help buying sights to mount on Chipmunk 22.

iakobos · Post by **iakobos** » Fri Mar 02, 2012 10:54 am

Our 4-H program is a little uncertain about what they are doing. In the meantime I need to set up a 22 rifle for my 8 year old son to practice with while the 4H program sorts things out. I have a Chipmunk rifle that currently has a cheap dovetailed mounted scope on it. What I would like to do is replace it with the correct sized peep sights for 10m target shooting. The front sight is held on with a machine screw and may be removed to add a target sight (I hope.)

I'm clueless about what rear sights to look at buying that could be mounted via dovetail and front sights that would mount to the barrel. Any help would be appreciated.

James

409impala1 · Post by **409impala1** » Fri Mar 02, 2012 11:26 am

look into Williams sights they have about anything.

jhmartin · Post by **jhmartin** » Fri Mar 02, 2012 1:27 pm

See if the gamo style will mount on these ... if your program has them the rear may just slip on and you may have to kludge something up for the front.

You can go with the cheap chinese gamo knockoffs as a start.

iakobos · Post by **iakobos** » Sun Mar 04, 2012 11:44 pm

Thanks for the responses. You know how it is, I was hoping someone would say, "Oh yeah I've done this before and you need to do this and this and buy that and that, and it's all done." Naturally that's not the case.

So, I've spent the last few days educating myself with what is available from Williams and trying to figure out how to make this work. Attaching a rear sight is not a problem. I'll probably go the inexpensive route and get a Williams WGRS-54 receiver peep sight with the dovetail attachment.
The obvious choice for a front sight is a Williams Target Globe Front Sight with a dovetail attachment. That was the easy part. Where I ran into trouble was how to attach the globe to a dovetail attaching base. The Cricket rifle (not a Chipmunk as I previously stated) only has a .500" diameter barrel. The smallest dovetail bases I have been able to find are for .600" barrels. Last night after pondering the situation I realized I need some kind of adapter to make the barrel bigger in order to attach a base to it.

My plan is to take a 1/4" black pipe coupling and drill the threads out of the center to make a hole .500" and slip it on the end of the barrel. The OD of the 1/4" coupling/adapter is .700". I can drill one hole on top of the pipe adapter and use the screw from the original post sight to locate the adapter. One or two holes will be drilled and tapped in the bottom of the adapter for set screws that will give it a positive/rigid attachment to the tip of the barrel. Back on top of the adapter two more holes will be drilled and tapped to allow the dovetail mounting base to be attached. Because the OD on the 1/4" coupling is .700" or .350" radius, this will allow the mounting of a Williams Target Globe Front Sight Attaching Base Screw On .450" Height .350" Radius

Hopefully, the .450" height adapter will put me in the ball park for the globe sight to match the height of the peep sight. Adding up all the numbers the base that the globe sits on will be .800" from the center line of the barrel (.250" barrel radius +.100" thick pipe adapter + .450" mount adapter = .800") . As best I'm able to measure it, the top of the factory installed receiver dovetail base that the peep sight will sit on is .700" from the center line of the barrel. I'll see if I can contact Williams and find out if the .100" difference will hurt me or not.

So that's the plan as of the moment.
Toss in a Williams Aperture Regular 1" Diameter (Target) with .050 Hole and I should be set. Shipping brings the total to $114.31.

iakobos · Post by **iakobos** » Sun Mar 11, 2012 9:57 pm

I thought I'd report back and say that the setup with the Williams sights is a success. I bought all the parts mentioned in the previous post. Everything mounted to the rifle with relative ease.

The 1/4" pipe coupling was drilled out with a 1/2" drill bit. Apparently the barrel is tapered slightly and it wouldn't quite slide all the way on. I used a 9/16 bit to drill out about 1/8" which then let the adapter slide on so the tip was even with the barrel. One hole was drilled and tapped in the bottom for the set screw. Two more holes were drilled and tapped in the top for 4-40 screws that were bought and cut to fit for mounting the .450" height dove tail adapter. The adapter came with metric screws and since I don't have any metric taps (hence the 4-40 screws) I didn't use them on this part (but the screws came in handy later.)

The target globe slides right on to the .450" dovetail adapter and is easily taken off to have different inserts installed.

The receiver sight slid onto the dovetail stationary mount base with a little effort. The downside to using the WGRS-54 sight is the 1" diameter target aperture hits the base of the sight about half way up the elevation. This wasn't a big deal since it does allow the sight some elevation. The whole stationary mount base and receiver sight assembly had to be elevated about 1/4" above the receiver. That's were the long metric screws from the .450" height adapter came in handy. I used a shim to hold the base and receiver sight assembly in the correct height and the screw was then the correct length and thread size to fasten the assembly to the top of the receiver.

I still need to do a little more work. The globe inserts aren't quite the right size to get the best sight picture on the target bull. Unfortunately, Williams doesn't seam to make any other inserts besides what came with the globe. I'm going to try some Redfield or Lyman inserts and see if they fit the Williams globe.

Here's three shots from bench rest with a 20MPH West Texas crosswind. I was still getting the windage correct on the left and right. The bulls-eye was the final shot.