I have GM drop-in barrels for my Renegade in .32, .36,.45, .50,and .54. As stated in an earlier post, they all like a rather tight ball and patch combo for the utmost accuracy, but do tolerably well with easier to load combos that don't require a brass or steel ram rod. All the above barrels have slow twist for round ball use. I currently have the .32 barrel up for sale on this forum.