Here is an eBay listing for them. I got mine off the Green Mountain website for $36 each.
9mm Barrel Blank 7.9" Cut Off 1:10 | eBay
Find many great new & used options and get the best deals for 9mm Barrel Blank 7.9" Cut Off 1:10 at the best online prices at eBay! Free shipping for many products!
|9mm Barrel Blank 7.9" Cut Off. 9mm barrel blank. These barrel blanks are 7.9 Inches long with a twist rate of 1:10 and .355 diameter for 9x19mm or 9mm Luger bullets. These blanks are crowned on one end to save you time, and ready to be chamber reamed on the other end. These barrels are cut from Green Mountain blanks and left over from shortening. These blanks are black nitride treated and have a thread of (1/2" x 36). The barrels have a slight contour profile as shown with the largest diameter end having a 0.75” Inch diameter and the smaller diameter end having a 0.69” diameter. The listing is for one barrel blank.|