Mr Bell is fifth-generation at the helm of historic Shag Valley Station, a 4900ha property on the Pig Root, between Dunback and Green Valley.
The Bell family hosted a Beef and Lamb New Zealand Farming for Profit field day at the East Otago property last week.
Their association with the station dates back to 1863 when Sir Francis Dillon Bell bought the property from Johnny Jones, thus marking 150 years of ownership next year. In the early stages, it covered 65,000ha and carried 80,000 sheep.
His son, Alfred, who took over management of Shag Valley when he was 21, had a life of farming and science.
He was a Fellow of the Royal Microscopical Society, the Royal Chemical Society and the Royal Astronomical Society and also set up and copied one of the first telephones in the country.
Alfred's son, Frank, took over running the station after his return from World War 1, and he and his sister Brenda became pioneers of short wave radio and Morse Code and two-way radio communication with London and South Africa.
Frank Bell's son Alf - Johnny's father - was the next Bell at the helm and he was an early adopter of both computers in the farming business and embryo transplants for beef cattle.
Johnny Bell was partnership with his father from the mid-1990s until his parents retired to Lake Hayes in 2004. He and his wife have three children, Lucy, Henry and George.
The property itself, while gradually reduced in size over the years, is still extensive, comprising 1000ha of paddocks and 3300ha of tussock country, with 500ha non-grazeable and 100ha of trees.
Current stocking rates comprise 5000 mixed-age ewes, 1200 2-tooth ewes, 1500 ewe hoggets, 2500 lambs yet to sell, 190 mixed-age cows, plus 45 3-year-old, 65 rising 1-year-old and 50 rising 2-year-old cattle.
The base sheep flock was Romney while, for the hill, ewe hoggets were put to Cheviot rams and Cheviots were also used as chasers in the main mob.
The result was 1500-1700 first-cross ewes which were crossed with South Suffolk rams to provide export lambs.
The Bells ran merinos until relatively recently, when they decided it was not working.
Youthful exuberance for tipping them up and doing their feet had worn off and, due to health issues, Mr Bell was also trying to simplify the operation.
The Cheviot mob was quietly building up and, long term, he would not mind having all Cheviots on the hill.
Ewe-scanning has risen from 135% to 152% in 2011 and 7000 lambs from 5600 ewes was achieved overall, giving 120% lambing.
Alf Bell was instrumental in bringing the Simmental breed of cattle into New Zealand in the early 1970s.
While they were "magnificent animals", which "milked like crazy", they required a lot of feed and Johnny Bell also found their temperaments "getting a bit out of hand".
The Simmental has been phased out and crossed with the Angus and most of the stock was now a mix of red and black.
While it was called a Farming for Profit field day, for many farmers, it had been a case of farming for survival, particularly over the past 10 to 15 years.
It was only now, with store lambs around the $100 mark, "that things are starting to work", Mr Bell said.
Being able to get the lambing percentage "creeping up" had added significantly to the farm's bottom line while improved returns for wool had also made a significant difference.
The Bells had been selling store lambs for "a fair old while". The last time they finished lambs was back in the 1980s. They tried to target stores at 29kg to 30kg.
Analysis from Beef and Lamb showed Shag Valley's economic farm surplus (profit before tax plus manager's salary plus interest plus rent less managerial reward) return on capital was 2.1% in 2010/11, up on the 1.5% average for similar types of farms.
In 2010-11, store sales were 72%, compared with an average of 48% for similar farms but the lamb price at $99.52 was up on the average of $98.21.
Selling store lambs was the most profitable option for the property, Beef and Lamb central South Island extension manager Aaron Meikle said.
Shag Valley was a large property and the Bells were trying to run it reasonably efficiently and in a way that suited the environment best, Mr Meikle said.
CRT technical field officer Drew Carruthers said the use of direct drilling had been a "huge turnaround" for the station, mainly for moisture preservation.
Tenure review on the station was described by Mr Bell as "work in progress", after at least 11 years. It was a very frustrating and very slow, he observed.
Initially, what was being sought would have ruined the balance of the property and he advised anyone in a similar position to "stick to their guns".
They needed to think about their property for future generations and, "if you ... [wreck] the balance now" it was not going to make it easier for the next generation.