I tried something similar once. I had some 50cal REALs that were very tight in my 50's so I tried patching them and shooting them in my 54. I was using .020 ticking patch to make up the difference on the .510 bullets. They went down somewhat tight but shot about an 8" group at 20 to 25 yards as I remember. I think the technique would work if you could get the right patch and could get it to wrap around the bullet the same way every time but that is always the trick isn't it. I would say give it a try and see if you find a combination that works. I know with my inlines I can shoot round ball if I use a tight enough patch and get good results all the way up to around 70 or 80 grains of 777.