4al2,
Not conversions per se but what I am doing in parallel to the DR is making a titanium 21 shotgun. the only difference between the two is that the shotgun will have the standing breech the normal thickness and the original integral hammer and firing pin. Of course the material is different as well with the DR being 4340 steel and the shotgun grade V titanium. I am working out all the code on the DR before I put the more expensive titanium through it. I started this whole thing thinking I would make one with interchangeable barrels for both shotgun and DR. Well into the project I decided that the standing breech was not thick enough and I believed I really needed a bushed firing pin. A ruptured cap would do really bad things inside the receiver. I will try shotgun barrels on the DR to see how they work. They may be fine but I just don't know yet. The only part I haven't made thus far is the monobloc. You can see from the early part of this thread I used a donor set of barrels for the monobloc. I do have the initial code for a monobloc but haven't had the time to test in the EDM. I will though.

I made the most common mistake for first time builders and that is the contour and therefore the weight of the barrels. The good news is that as 45-70 they will be a pleasure to shoot I think but a nightmare to carry. The balance is likely to be pretty bad as well. However, you learn as you go and that is a big part of the whole thing. I have already bought reamers from Ron Vella to make a 6.5x57R set of barrels. So, in the future a new set in this beautiful little caliber is at least in my mind. I have the barrels, reamers and monobloc code. All I need is the rest of the stuff i.e. time.

In the very beginning this project was only to be about making a titanium 21 20ga shotgun. I blame the dedicated and talented group on this forum for getting me into the DRs. I guess I am easily diverted though. Anyway, the DR then became the focus with the shotgun lagging behind. This is a pretty long answer to your short question. I should have just said no-----Bill