Originally Posted by FullClip
Check out page 10 of your owners manaul:
Through our testing, Smith & Wesson has also found that there
are several brands and types of .22LR ammunition that do not
perform consistently or reliably. Consequently, Smith & Wesson
DOES NOT RECOMMEND that the following brands or types of
.22LR ammunition be used in your M&P15-22 rifle:
• Remington Golden Bullet • Remington Thunderbolt
• Remington Target 22 • Winchester Wildcat
• Any and all sub-sonic brands and types
They specifically tell you not to use sub-sonic ammo. bet they will fix it anyway, but if I were the warranty manager, things would be different.
they said it would not run consistently or reliably, and that they don't recommend them, it didn't say to Not use them.
plus i don't see how a underpower round could cause a oob discharge.