My ruger mark is a generational bash of the 123. The barrel here is a gen 1 now replaced with a bull gen 2. The bolts are compatible between all gens. The mag here is gen 4 which works OK. The real hard part was sourcing the grip. Took me 6 months of wait but caught one. The gun is now reliable and fun to shoot. This is a cool and simple project. I recommend you to scope a cheap grip for this. To sum up this long winded upload, is that 22s will always be cool.