Buckey,
According to the book I have "The Swedish Mauser Rifle" the twist rate for a M38 with either the 23.1" or 29.1" barrel would be 1:7.9
Hope this helps...
Got 3 of these myself and the 3rd one came to live at my house last Sunday and is a target model M96 with target sights. Would like to find a nice M38. Had a couple of leads but nothing yet..
Enjoy the rifle they shoot great..
DonT
DonT