The Freedom Arms revolvers are EDM rifled (or at least were at one time...)> I have shot my own hard cast out of my 654 FA at clocked velocities of 1800 fps with no appreciable leading, and what lead there was came out readily with some Hornady One Shot.
No less an authority than Wayne Gibbs of Hensley and Gibbs told me years ago that if a cast bullet is of the proper hardness, is sized right, and has the right lube on it, a gas check is unnecessary for anything below 2000 fps. But getting all three of the above items can sometimes be very tricky, especially with commercially cast projectiles.
All I would recommend is to try them and watch for increasing smoke levels. That is indicative of either molten lead clearing the barrel or lubricant breaking down, and usually it is the lubricant.