I shoot Steel Challenge and use a chamber block that goes in the mag well and sticks up between the bolt and the chamber.


I find it easier to get in than a flag that needs to be threaded into the small chamber of .22 and it holds the bolt back and lets the chamber cool off some. Being bigger it's also easier to manipulate and find on the table when it's time to bag my rifle.



Smith-Wesson M&P 15-22 Magazine Safety Flag - FGS Engineering