S+W 22S fragmenting?

[lord1234]

I have a 22S(bull barrel, target rail, etc). This gun is awesome, the only thing is every once in a while, i get tiny fragments of something hot in my right hand. It hurts(briefly).

At first I thought it was the bumper, so I replaced the plastic bumper. Nope.

I am sort of clueless. The gun shoots/feeds/extracts flawlessly with federal wally world bulk pack.

Please give me any advice you might have on whats causing the fragmenting?

 

[Big Daddy 45acp]

Could be a bit of hot, unburned powder.

 

[vellnueve]

Make sure the breech is fully closed before each shot. Might need some cleaning.