[SouthSideScubaSteve]

My LGS has “22LR conversion kits” for 223/556 AR-style rifles that appear to be a bolt carrier/bolt assembly and special magazines that they say you can swap out in the field and go from firing center fire to rim fire or vice-versa… 2 Questions:

Does anyone have any experience with these ?
Will they work with a piston driven rifle like the SR-556??

 

[KSR]

Conversion kits are not the best solution, you typically get poor accuracy with them due to having a slightly oversized bore and the wrong twist rate and you have to worry about fouling the gas port with lead.

In the case of the SR they won't work at all due to the op rod being longer than the gas tube of a DI gun.

If you want a .22lr AR either buy a dedicated .22 upper or a complete rifle like the S&W M&P 15-22.

 

[SouthSideScubaSteve]

...you typically get poor accuracy with them due to having a slightly oversized bore ...

That's what I thought orignally, but the guys at the LGS kept saying that the difference in bullet diameter from 22LR to .223/5.56 was within "tolerances" .. Didn't make sense on the surface, and like most thing that sound to good to be true, I figured it was!

Thanks!