Massive caveat: These measurements were done as precisely as my tools will allow, but that does not imply any particular claim to accuracy.
Apologies I didn't take the time to figure out how to paste a table into this system.
First number is length of reservoir (mm). Second number is reservoir capacity (ml).
Platinum 30, 0.6
Sailor 30, 0.6
Lamy 33, 0.75
Waterman 27, 0.6
Parker 27, 0.55
Unbranded 25, 0.6
Montblanc 25, 0.8
No-name Chinese 27 0.75
Sheaffer-style neck 25, 0.7
I have done numerous measurements too, with an electronic mini scale.
They include the ink in the feeder with all air bubbles expelled. These are the results:
Platinum 3776: 0.72-0.8ml
Sailor large 21k pro gear: 0,73ml
Sailor 14k pro gear: 0.67ml
Sailor KOP pro gear: 0.9-0.95ml
Franklin Christoph 45 (with kawaco mini converter): 0.53ml
Franklin Christoph P20 (with kawaco mini converter): 0.8ml
Franklin Christoph 1901 (with international converter): 1.12-1.15ml
Franklin Christoph 02 (with international converter): 1.12ml
Pelikan M400-405: 1,65-1,75ml
Pelikan M600: 1,72ml
Pelikan M805 (numerous): 1,6-1,75ml
Pelikan M1000: 1,94ml
Montblanc 146: 2ml ( may vary on how you reassemble the piston after cleaning)
Pilot custom 823: up to 2,45-2,5ml (if you apply the 2 step filling technique shown on youtube).
Edited by inkking, 17 March 2019 - 08:40.