This breed, earlier known as American Bulldog -Johnson type, have been renamed by Mr. Johnson himself, the originator of the breed, to John D. Johnson Bulldog. There are still clubs and registries that classifies this "breed" as American Bulldog Classic/Bully type, but John Daniel Johnson of Summerville, Georgia, should be given credit for his lifelong work preserving and developing the Bulldog of his childhood, and the name JDJ Bulldog should be fully accepted by all parties.
Mr. Johnson started his breding program right after World War II, buying a few of the best American Bulldogs that he could find and afford, which proved to be a hard task since good bulldogs were almost extinct.
It is no secret that Mr. Johnson used a throw back AKC Bulldog, West Champs High Hopes, in his breeding in the early 1970's. This dog were also used by Mr. David Leavitt in his breeding program to create the Leavitt Olde English Bulldogge. Out of the breeding with West Champs High Hopes only two females were used further in Mr. Johnson's breeding program; Bullmeads Queen & Sugar Doll, and these two started the Machine line and the Sugar Doll line.
According to Mr. Johnson no other dog breeds, exept West Champs High Hopes, have been used by him creating the Johnson Bulldog, but he have kept breeding for the Bully type.

Example on a throwback AKC English Bulldog.
Spike, owned by Sharon Maguire.
(Note; this dog (Spike) was not used by Mr. Johnson)

While the Standard American Bulldog are known to be a better dog for working cattle and hogs, the JDJ Bulldog is known to be a better dog for personal protection. Its protection instincts comes naturally and it will guard you with its life. As a guard dog the JDJ Bulldog is excellent, and it will keep every intruder off your property.
The JDJ Bulldog is a very powerful and strong breed, but it is surprisingly athletic considering its size and built.
It needs a firm hand both in the holding of the collar and in the raising of the dog.