aximum hit
For melee mode the strength bonus of the salamander is used, which is 71 (same as a dragon longsword).
For ranged mode the ranged strength bonus of the tar is used to decide the maximum hit. The black salamander uses harralander tars which have a ranged strength bonus of 49 (same as rune arrows).
The maximum hit for magic mode uses the "magic damage bonus" of the salamander. This bonus is not visible in the equipment stats, but is equal to 92 for the black salamander. Damage boosting items such as the slayer helmet (i) and occult necklace can be used to increase the max hit.
The max hit (Hitmax) formula for salamanders is as shown in fig.1, where "Magic" is your visible magic level and "Bonus" is the "magic strength bonus" for the salamander, in this case 92. This gives us the formula for the black salamander as shown in fig.2.
The table below shows maximum hits from level 70 to level 125. Like all other magic attacks, the max hit damage can be increased by using magic damage boosting equipment.
https://oldschool.runescape.wiki/w/Black_salamander