I have finally gotten the super safety to work with 22lr. It took A LOT of trial and error. I hope I can be clear and articulate with communicating the key points as I see it. First off, my set up. I am using a standard milspec ar-15 lower which I milled out from an 80% lower. It has a low rear shelf. I started with a milspec FCG but replaced the springs with lighter ones and I also use a tail-less hammer. My trigger pull is about 5.5 lbs as measured in the center of the trigger. I am using a CMMG 22lr conversion kit. I have replaced some of the internals of the kit with items from bore buddy. The key items for my setup are as follows. I have the improved firing pin (Which looks to my eye as the same as the stock firing pin except that the portion that strikes the rim of the cartridge is ground down on the sides to make the striking portion thinner than the stock pin. This translates to higher pounds per sq inch) I am using the stock 5lb recoil spring. I replaced the extractor with the borebuddy improved extractor. I am using 2 buffer plugs. One from bore buddy and one that I 3d printed. I have it on my list to print out a doulble length plug, thus adding more tension on the buffer spring to keep the CMMG carrier from moving backward towards the buffer. I use the bore buddy adjustable weight kit and 4 of the steel weights in the steel weight carrier. The entire added weight to my system is 52grams. This is a bit higher than I have see others use but this is to be expected because I am using a tail-less hammer and lighter FCG springs. I arrived at this weight configuration by using a casio elixm camera capable of 1000 frames per second. This was the only way I could reliably ensure that I did not have any bolt bounce which would result in light primer strikes and a dead trigger.
I started this journey using a CNC machined supersafety and lever in conjuction with the bore buddy adjustable trip. I could not get the system to cycle reliably. In the end, I had to download the 22lr SS lever from printables.com. I had to make further modifications to the lever, which I will cover later. I also had to ditch the bore buddy adjustable trip. I had to download the cmmg compatible trip from printables.com and a make significant modifications to this trip. I would not have gotten this system to run reliably if I was not versed in 3D printing and also 3D design. So now, on to the 3d files and how I modified them.
For the lever I noticed that the stock lever has too much play for use with the CMMG conversion kit. The CMMG 22lr bolt has a much shorter length of travel as compared to a milspec AR-15 bolt. This means that the super safety must cycle with less linear input when using it for 22lr. What's important to note is that it's not how far the lever moves from front to rear, and rear to front. It's how much rotation the cam turns during the rear and forward travel of the bolt. Because of the play in the stock lever, the cam was not rotating enough to do it's job properly. You may notice during function checking that you can get the trigger to reset by manually moving the lever to the rear. At the point of reset, it can still be possible to pull the trigger as the trigger pull can also rotate the cam forward. This will cause the hammer to follow the bolt and you will get a light primer strike and dead trigger. Even with the borebuddy trip adjusted for maximum rearward travel, it was not rotating the cam enough because of excessive play. So I downloaded this file: https://www.printables.com/model/1265444-modified-super-safety-lever-for-22lr
The lever still had too much play to I used OpenSCAD to import and modify the .stl file. I resized the only the bulb end that slides into to the cam. If you imagine virtually cutting off the bulb from the lever (with the lever being along the Y axis) I resized the bulb by increasing the x-axis dimension of the bulb by 14% and the y-axis of the bulb by 16%. This made the lever snug in the cam with enough freedom that I can easily push the SS from safe, fire, and SS modes.
Next I had to import the CMMG trip into OpenSCAD and alter some critical aspects for rear and forward travel limits. I started with this file: https://www.printables.com/model/1264353-ss-trip-for-cmmg-22lr-adapter
The process by which I altered this file is more complicated than how I resized the bulb on the lever. I had to use the projection command to make 2 dimensional cross-secions at various points along the trip. I them used linear exctrude on these cross-sections to make them the size that I desired. This way I could make numerous trips for trial and error by just adjusting some variable in between attempts. I also had to make the pocket in the trip a tad smaller than the original pocket. What's important as you resized this trip is to make sure that you get enough rear travel on the trip to rotate the cam through reset and to safe so that the trigger is prevented being able to force the cam forward by applying extra pressure to the trigger. Then you need to adjust the forward travel of the trip so that the trigger is only able to be pulled as the bolt is arriving at the closed position.
summary of key points:
use a 3d printed lever with resized bulb to reduce the play, thus increasing cam rotation.
Don't bother with the borebuddy adjustable trip because it does not have enough adjustment to the forward travel to time the cam rotation with the bolt as it is closing, Instead modify the 3D printable trip for your system.
use an adjustable weight kit to prevent bolt bounce. Use an enhanced extractor and firing pin as needed. These certainly improve the system however I don't think they are as critical. Use a buffer plug or two.
One final note, I am using 40gr high velocity ammo. I tried 3 different brands, CCI mini-mag, Remmington Thunderbolt, and Aguila Super Extra. for the price, I like the Aguila as you can get a 500 round box of copper plated rounds for just under $40 US. The CCI mini mags are fantastic however more expensive. The Thunderbolts work okay however you get black thumb when loading the magazines and plenty of lead fouling in the barrel requiring more frequent cleaning.
I hope this helps you all to get your HTSS running with .22lr ammo. It is so much more cost effective than any other kind of ammo.