I remember reading somewhere that W J Jeffery made a snap forward type underlever action for their double rifles that the firm considered a considerable improvement over both the toplever as well as over the rotating type underlever. If I remember right, one of Austyn's books has a picture of one.

Does anyone make this action today and did it offer any real advantages over the more conventional top and underlevers or was it a marketing gimmick?

Thanks and if someone owns one of these please post pictures. I am sure that I wouldn't be the only one drooling over the pictures.

Best wishes and good hunting!