Just to make such substitution easier, below are measurements from numerous flutes showing outer headjoint diameter in order of increasing size. Headjoints with the same diameter are interchangeable; and with appropriate teflon or paper shims, a headjoint can be made to fit any flute below it in the list.

Listed outer headjoint diameter measurements are only approximate.  Tenons tend to be out-of-round and quite flexible.  Listed in order of increasing headjoint diameter as determined by substitution of headjoints with flute bodies.

Tube column indicates al=aluminum; bs=brass; sg=solid gold; ss=solid silver, sp=silver plate, wd=wood, st=stainless steel.

Wall thicknesses were measured at headjoint tenon and body tenon and averaged over several measurements using a modified micrometer (see image -- I ground a large steel ball bearing down to 300/1000" to fit inside tubing). Accuracy is somewhat questionable due to wear, tenon burnishing, and GoferJoe's somewhat suspect ingenuity.

Sounding length measurements were made with headjoints fully inserted, from center of embouchure to end of foot (c-foot unless otherwise indicated); these measurements are in millimeters since it is convenient to think of 600mm being approximately A-440 for normal cylindrical bore flutes.

Headjoint Diameters (in) / Wall Thicknesses (in) / Sounding Lengths (mm)
(diameters only relative with approximate measurement, H=headjoint only)

Head   Flute Maker                         Tube  Walls (in)    Sounding
Diam   Model or Serial Number                    Head / Body   Length (mm)
.767"  Rampone & Cazzani 05353 ('80?)        sp  .014  .020    596
.768"  Haynes 18530 ('47 Laurent)            ss  .010  .011    596
.768"  Rudall Rose Carte 594 (1870?)         ss  .0075 .011    587/571
.769"  Armstrong Heritage H2807 ('74?)       ss  .012  .0135   600
.771"  Haynes 23950 ('54 14k)                sg  .0105 .009    635b
.773"  Haynes 28017 ('59)                    ss  .013  .013    598   
.773"H Lamberson, N.D. HJ                    ss  .0135
.773"  Haynes 23447 ('53 handmade ch)        ss  .013  .013    599
.773"  Worswick, Ashton 10 ('30?)            ss  .014  .014    600
.773"  Richards, Br'klyn ('20?)              ss  .011  .011    607
.773"  West, P.L. 1070 ('75?)                ss  .0135 .0135   637b
.774"  August Bonneville 2155 (1886)         sp  .012  .012    600
.774"  SML Alliance (no S#)                  sp  .015  .015    596
.775"H Lorello, Eugene E (80?) gold plate    ss  .0135
.775"  Philipp Hammig 19154 (88?)            ss  .014  .015    595
.775"  Stramalux SML 907                     sp  .015  .013    594
.775"  Boosey Pratten's 10604 (1879?)        ss  .011  .013
.775"  Armstrong 80 V1392 ('72)              ss  .014  .018    602
.775"H Borouchoff HJ ('85 stainless)         st  .011
.775"H Haynes HJ prototype                   ss  .012                
.775"  Almeida 160 w/ Cooper HJ ('72)        ss  .0125 .013    635b
.775"  Powell 1775 ('57)                     ss  .0125 .012    635b
.775"  Powell 2577 ('65)                     ss  .014  .013    636b
.775"H Altus .958 Britannia seamed ('98)     ss  .0135
.775"  Eudy, S.M. 7-16 ('75")                ss  .0135 .0135   633b
.775"  Philipp Hammig 4282 ('62?)            ss  .014  .0135   594
.775"H Prima Sankyo High Wave HJ #1          ss  .014      
.776"  Rampone 1462 ('30?)                   sp  .012  .0135   643b
.776"  Marigaux 1359 ('50)                   ss  .013  .013    599
.776"  Buffet Crampon & Cie 844 (1885-95?)   sp  .0125 .0125   605
.776"  Jack Leff 700 ('75?)                  ss  .013  .0135   596
.776"  Miyazawa Standard 1618 ('75?)         ss  .015  .015    597
.776"  Rive-Gautié‚ 1756 (1895?)             ss  .012  .0115   600
.776"  Lebret 4242 (1910?)                   sp  .014  .013    602
.777"  Yamaha 821 1433 ('94?)                ss  .014  .016    596
.777"  Berteling 30 wood(1865?)              wd  N/A   N/A     588
.777"  Noblet/Leblanc 5949 ('35?)            sp  .014  .017    600
.777"  Prima Sankyo Artist 21040 ('83?)      ss  .015  .015    633b  
.777"H Prima Sankyo "traditional"            ss  .014                
.778"  Muramatsu 29529 ('82)                 ss  .015  .014    595
.778"  Muramatsu 27126 ('81)                 ss  .0145 .015    594   
.779"  Miyazawa MC-500 ('83?)                ss  .015  .016    598
.781"  Yamaha 521 1149 ('91?)                ss  .014  .015    597   
.781"  Yamaha 892H 3646 ('95?)               ss  .0145 .015    633   
.781"H Miyazawa cusped HJ                    ss  .016
.781"  Natsuki NF-103 ('82-85?)              ss  .014  .014    600
.781"  Conn 10210 ('06 unibody)              sp  .011  N/A     587/573
.781"  Le Maire 7903                         sp  .015  .0175   601
.781"H Fajardo cylindrical w/ wedge ('70?)   ss  .014
.782"  Armstrong Heritage H2230 ('72)        ss  .016  .017    637b
.782"  Robert Malerne 339 ('35?)             sp  .017  .018    600
.782"  Artley Artist 58629 ('59)             ss  .015  .016
.782"  A. G. Badger (1868-80 to low Bb)      sp  .013  .014    667Bb
.782"H Prima Sankyo High Wave HJ #2          ss  .012
.782"H Haynes HJ prototype                   ss  .012
.782"  Artley Artist 386663 ('73)            ss  .0155 .0145   600   
.782"  Artley Super Artist 109184  ('63)     ss  .015  .016    598   
.782"  Berteling silver (1860?)              ss  .011  .014    588
.782"  Haynes 7458 ('23 commercial)          ss  .0145 .016    601   
.783"  Haynes 15210 ('37 commercial)         ss  .0165 .016    603
.783"  Yamaha 61 1968 ('79?)                 ss  .016  .016    593
.783"  Bettoney 1532 ('18? w/ C#)            ss  .010  .014    597
.783"  Artley Wilkins 98838 ('62)            ss  .0135 .0155   598   
.784"  Hans Reiner 858 ('67?)                sp  .016  .015    595
.784"  Haynes 6984 ('22 commercial)          ss  .0165 .018    601
.784"  Gemeinhardt 2SP F57730 ('80?)         sp  .016  .0165   601
.784"  Armstrong 90 33258 ('54?)             ss  .017  .0195   601
.784"  Gemeinhardt M3SS 3501 ('55?)          ss  .010  .016    601
.785"  Artley Super Artist 6880 ('50?)       ss  .016  .018    599
.786"  Gemeinhardt M2 A20820 ('75)           sp  .0165 .014    600
.786"  Uebel 116-69-1481 ('69 aluminum)      al  .013  N/A     597
.788"  Klingson Hammerschmidt's ('50?)       sp  .014  .017    598   
.789"  Grassi Milano 5237 ('60?)             sp  .0185 .017    598
.790"  C. Krusp ('50?)                       sp  .016  .018    600
.790"  Bettoney M33 ('48?)                   ss  .018  .018    593
.791"  Prof. Romeo Orsi ('50?)               sp  .020  .020    605
.791"  Christensen & Co. 1552 ('25?)         sp  .020  .020    602
.790"  William Winthrop Haynes 365 ('20)     ss  .017  .021    603
N/A    Gautrot aîné (1880? simple)           wd  N/A   N/A     519

Harmony Flutes
.695"  Armstrong Eb 27-20503 ('77)           sh                510
.972"  Emerson A3CT Alto 76582 ('99)         ss  .017  .025    787
.975"  Yanagisawa Alto 3002 ('84?)           sp  .020  .019    787
1.000" Opperman Alto 121 ('57-58)            sp  .026  .028    793
1.025" Yamaha A421 Alto 1145 ('91?)          bs  .019  .019    782
1.035" Prima Sankyo Alto 6570 ('74?)         ss  .016  .018    788
1.062" Rudall Carte Alto 8782 ('61)          ss  .019  .019    789
1.125" Ogilvie Bass 0064 ('60?)              sh  .025  .025    N/A
1.165" Rudall Carte Bass ('54?)              ss  .020  .020    N/A
1.550" Albisiphon Baritono ('20?)            sp  .025  .025    N/A

Piccolos
.464"  Armstrong Piccolo ('67?)              sp  .015  N/A     269
N/A    Yamaha YPC62 Piccolo 18566 ('85?)     wd  N/A   N/A     262
N/A    Two Early Keyed Simple Piccolos       wd  N/A   N/A     250


NA indicates measurement not available; for example, wall thickness not measured in wood, aluminum, or unibody (footless) flutes.

Ferree's Tools Inc. flute tenon sleeve sizes:
.777"  Armstrong head
.785   Gemeinhardt head & foot, Yamaha foot, older Haynes
.786"  Blessing foot
.787"  Bundy head
.788"  Blessing head
.792"  Bundy foot, Artley foot
.794"  Artley head

Images © J. W. Sallenger