this rifle was still acquired as a C&R and his license was still used to purchase it. not having that in his bound book sounds more like a violation than not and technically all weapons purchased with a C&R is a deposition to yourself and is to be used for your personal collection...
I think you have a misconception of what a Class 03 Collector of Curio and Relic Firearms FFL is. It is exactly
for acquiring firearms for your personal collection. So you don't enter a disposition to your self for a firearm you bought using your own C&R FFL. As long as it remains a C&R firearm.
It is also specifically stated that you can not "engage in the business of dealing in firearms" with a C&R FFL. Selling a gun to "improve your collection" is allowed, and that is where the disposition comes in. That subject leads to a whole new debate. Some feel it is improving your collection, not engaging in being a dealer to buy a whole case of guns, and sell all but one for a profit enough to cover the expense of the one you keep. That one seems like a bit of a stretch to me.
When I say enter it as a disposition to your seld in your bound book I am going by what I have been told by many. If mit is no longer a C&R firearm. it does not belong in the book. That doesn't mean you have to get rid of it, just take it off your book.
as far as my modification of CR firearms question, I found an answer elsewhere on the Internet and my local ATF office confirmed.
It really was a no-brainer,,
In case anyone else out there doesn't already know:
Basically if you modify a C&R purchased firearm and its no longer C&R compliant you have to transfer it off your Bound Book. Basically the ATF said to transfer it off to your personal collection and comment that it was being customized. Once its off your bound book you can treat it like any non-C&R firearm you own. As long as your modifications are legal (NFA, 922r) you should be good to go.
The BATF works very hard at making the rules very confusing I think!