How many of Babe Ruths home runs were ground rule doubles now?

Answer 1

Technically these were and are today "automatic doubles," not "ground rule doubles." This is because the rule is identical in all ballparks, and is not a ground rule specific to a particular park.

But all announcers and most fans still refer to them as "ground rule doubles."

About 22 or more But....

The number of home runs that Babe Ruth hit that bounced over the wall, and counted as a home run will never be known because it was counted as such. It was estimated that players of that era hit about 2 home runs a year, that bounced over the wall. Counting from 1920 when Babe Ruth became a full time hitter for the Yankees until 1930. (1931 the rule was changed making a ball that bounced over the fence a ground rule double) Babe Ruth would have had about 22 (or more) ground rule doubles that were counted as home runs.

But the Babe lost more home runs than gained because there was also a rule that the Baseball that cleared the wall in fair territory, also had to land in fair territory to be counted as a home run. Further, the rules once stipulated that an over-the-fence home run in a sudden-victory situation would only count for as many bases as was necessary to "force" the winning run home. For example: In a tie game, a ball hit over the wall with a runner on first to end the game would only count as a triple. It was estimated that Babe Ruth would have hit 104 home runs in 1927 when he had 60 home runs counted, and lost between 50 -78 home runs overall, during his career because of these rules.

Answer 2

The Babe Lost more HRs than gained

The number of home runs that Babe Ruth hit that bounced over the wall, and counted as a home run will never be known because it was counted as such. The stat of home runs that bounced over the wall was never kept.

It was estimated that players of that era hit about 2 home runs a year, that bounced over the wall. Counting from 1920 when Babe Ruth became a full time hitter for the Yankees until 1930. (1931 the rule was changed making a ball that bounced over the fence a ground rule double) Babe Ruth would have had about 22 (or more) ground rule doubles that were counted as home runs.

But the Babe lost more home runs than gained because there was also a rule that the baseball that cleared the wall in fair territory, also had to land in fair territory to be counted as a home run. Further, the rules once stipulated that an over-the-fence home run in a sudden-victory situation would only count for as many bases as was necessary to "force" the winning run home.

For example: In a tie game, a ball hit over the wall with a runner on first to end the game would only count as a triple. It was estimated that Babe Ruth would have hit 104 home runs in 1927 when he had 60 home runs counted, and lost between 50 -78 home runs overall, during his career because of these rules.