I don't recall that at all Karinna. Culhane did swab and test the 22 though. She tested the barrel and the trigger.
http://www.stevenaverycase.org/wp-content/uploads/2016/01/Steven-Avery-Trial-Exhibit-313.pdf
Item DD - one .22 caliber rifle (agency tag# 647)
Item DD1- swabbings from the trigger and trigger guard of item DD
Item DD2- swabbings from the end of the barrel of item DD
Blood was not detected from items H, Q, W, AC, AJ, AK, Cl, CJ1, CJ2 , CR2 , CR3 , CR5 , CR6 , CS,
DD or EG.
In addition, human DNA isolation was also performed on items All, A23, AJ, AK, L, M, N, T, S, U, CR1, DD1 and DD2 . Partial DNA profiles were obtained from items A23 and
DD1 . Due to the limited genetic information these profiles are insufficient for interpretation.
A trace level of human DNA was detected from items L, N and
DD2 . No human DNA was detected from items L, S and U. No further analyses were performed on these items