I don't think every ship that gets hit by reclamation actually gets converted. I think that the killing blow is what does the conversion with the latest patch. That's why leeches aren't as awesome as they used to be.
Actually, the logic is MUCH more complicated than that.
This logic is as of the latest patch at the time of this writing (5.020), as the change was made in version 5.001
Reclamation damage is stored separately from normal damage, and is not visible to the user. If at the death of the ship, the reclamation damage/Max HP of that ship > some ratio (50% I think), the ship is reclaimed.Base
reclamation damage is the same as the base weapon damage.
However, where it gets complicated is that depending on mark level, reclamation damage can get a bonus (even though normal damage still get computed normally)
From the release notes (v. 5.001)
If the reclamator is 4 mks higher than the target (mkV shooting mkI), multiply by 64.
If the reclamator is 3 mks higher than the target, 48.
If the reclamator is 2 mks higher than the target, 32.
If the reclamator is 1 mk higher than the target, 16.
If the reclamator is the same mk as the target, 8.
If the reclamator is 1 mk lower than the target, 4.
If the reclamator is 2 mks lower than the target, 2.
If the reclamator is 3 mks lower than the target, 1.
There is no 4-mk-lower case because mkV are not reclaimable.
Worse, some units, like the Neinzul nanoswarm, get a reclamation damage bonus for all hits ON TOP of these values. (for the nanoswarms, 10x I think)
And to finally round out this madness, these rules only apply to normal reclaimers. Zombie reclaimers use a different method of reclamation bonus damage tracking to determine net reclamation damage (though the same ratio of damage to reclaim rule still holds true)
The rules for 5.000 are much simpler, but much worse for the usefulness of reclaimers. In 5.000, net reclamation damage is the same as normal damage (no global bonus shenanigans, only ship type specific bonuses), but with the restriction that a Mk. X reclaimer flat out CANNOT reclaim anything that is 2 or more mark levels above it, no matter how much reclamation damage it managed to inflict.
Base attack power of reclaimers were nerfed pretty hard from 5.000 to 5.001 to compensate for this change, but with the buff that they can now reclaim much more stuff.