Roger, just do some measurements.
1. With the rest/bags, make sure the top of the bag (where the stock sits) is 1/2 or more above whatever retains the bag on the rest or top.
I can't imagine that a Hart w/ a Bald Eagle top & bag would have any issues in this regard. But when you listed your available rests & bags, you weren't quite specific enough about which bag with which rest. For my LG, I have a Hart pedestal with (1) a Bald Eagle windage top & bag, (2) Hohen windage top & bag, and (3) one of Butch's joystick tops, with a Protektor bag. I also have an early model Farley as a complete rest/top.
But there are different models of bags, and things change as they are filled, so there is no way around checking for yourself.
For rifles I shoot free recoil (up to 6.5/06 AI), I use a joystick. With the Farley & an Edgewood bag, I had to put a spacer between the bag & bottom of the container.
For rifles I hold on to the forearm to shoot -- .30 magnums & .338s -- I use the Hohen top & bag. I had to carefully re-pack the Hohen bag, just to be sure there was *well more* than 1/2 inch between the clamps that secure the bag & the part of the bag where the stock sits.
2. Next, set the rifle up in the rests/bags & check for 1/2 inch up the sides of the stock. You didn't say just which Kelbly stock you had. Most of them don't have "rails" or even fake "rails," so you need to ensure the slop in the bag ears doesn't overhang the stock enough to make contact.
With *my* Edgewood that fits the Farley, the ears are only 1/2 inch tall, and there is no slop to them, so no problem. Same with the Hohen. The Bald Eagle and Protektor bags though, depending on the model & how you've filled them, just might make contact more than 1/2 inch up the stock. Likely it isn't touching too far up, but you need to check. Safest solution BTW is to take the bag to somebody who can sew heavier materials, and have the ears sewn so they won't fill with sand more than one half inch above the part of the bag the stock rests on.
For a Heavy Gun with a mechanical rear pedestal, you've got to do the same measurements.
Hope this helps,