I have some hypothetical questions regarding guns that are not C&R eligible when you get them but may become so while you own them and in relation to recording them, selling them, etc.

I had read a while back that even if you buy a C&R gun without your license (or perhaps before you got your license) you still have to record it in your book as a disbursement if you sell it. What happens If you buy a gun that is not C&R eligible but it becomes eligible after you own it (i.e. it was 48 years old when you bought it and it turns 50 years old while you have it)? Do you have to record it in your bound book when it becomes C&R? Do you have to record it as a disbursement if you sell it?

How about if a gun is given to you that is C&R eligible? Should that be in your book? Case in point, my father gave me a rifle for deer hunting that was made in the 1950s which would make it eligible. A father to son private transfer is legal but should that be recorded in my book? If it doesn't have to be added to my book but is technically a C&R gun would I have to record it if I were to sell it?