| Men 100m Freestyle Swimming III World Championship 1978 West Berlin - Monday, 28th August - Gold Medal: David McCagg, United States | 
| Final |   | time |   | gap | L | pts | ag | 50m |  | 1. David McCagg |   United States | 50.24s | CR |   | 4 | 848 | 20 | 24.12s  |  | 2. Jim Montgomery |   United States | 50.73s |   | +0.49s | 3 | 824 | 23 | 24.54s  |  | 3. Klaus Steinbach |   West Germany | 50.79s | ER | +0.55s | 5 | 821 | 24 | 24.75s  |  | 4. Marcello Guarducci |   Italy | 51.71s |   | +1.47s | 6 | 778 | 22 | 25.08s  |  | 5. Fernando Canales |   Puerto Rico | 51.74s |   | +1.50s | 2 | 777 | 18 | 25.04s  |  | 6. Andreas Schmidt |   West Germany | 51.78s |   | +1.54s | 7 | 775 | 18 | 25.50s  |  | 7. Pelle Holmertz |   Sweden | 51.83s |   | +1.59s | 1 | 773 | 18 | 25.64s  |  | 8. Per-Alvar Magnusson |   Sweden | 52.36s |   | +2.12s | 8 | 749 | 20 | 25.86s  |   
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| World Record: Jonty Skinner, South Africa 49.44s (23.83s) |  | Championship Record: Andy Coan, United States 51.23s (24.76s) 1975 |   
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 Heats - , --th August |  | Best 8 times advanced to Final>.  |   
| Heat 6 |   | time |   | gap | L | ag | Rk |  | 1. David McCagg |   United States | 50.39s | CR |   | - | 20 | 1. |  | 6. Andreas Schmidt |   West Germany | 51.86s |   | +1.47s | - | 18 | 2. |  | 8. Per-Alvar Magnusson |   Sweden | 52.15s |   | +1.76s | - | 20 | 3. |   
| Heat 5 |   | time |   | gap | L | ag | Rk |  | 3. Jim Montgomery |   United States | 51.63s |   | +1.24s | - | 23 | 1. |  | 9. Martin Smith |   Great Britain | 52.65s |   | +2.26s | - | 20 | 2. |  | 10.Graeme Brewer |   Australia | 52.70s |   | +2.31s | - | 19 | 3. |   
| Heat 4 |   | time |   | gap | L | ag | Rk |  | 4. Marcello Guarducci |   Italy | 51.80s |   | +1.41s | - | 22 | 1. |  | 13.Sergei Kopliakov |   Soviet Union | 52.96s |   | +2.57s | - | 19 | 2. |  | 21.Peter Szmidt |   Canada | 53.52s |   | +3.13s | - | 17 | 3. |  | 32.Remmy Schaap |   Netherlands | 54.82s |   | +4.43s | - | _ | 5. |   
| Heat 3 |   | time |   | gap | L | ag | Rk |  | 5. Fernando Canales |   Puerto Rico | 51.85s |   | +1.46s | - | 18 | 1. |  | 7. Pelle Holmertz |   Sweden | 51.91s |   | +1.52s | - | 18 | 2. |  | 16.Paolo Revelli |   Italy | 53.10s |   | +2.71s | - | 19 | 3. |   
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| Heat 2 |   | time |   | gap | L | ag | Rk |  | 11.David Lopez-Zubero |   Spain | 52.79s | NR | +2.40s | - | 19 | 1. |  | 14.Mark Morgan |   Australia | 53.03s |   | +2.64s | - | _ | 2. |   
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| Heat 1 |   | time |   | gap | L | ag | Rk |  | 2. Klaus Steinbach |   West Germany | 51.34s |   | +0.95s | - | 24 | 1.  |  | 17.Bill Sawchuk |   Canada | 53.20s |   | +2.81s | - | 19 | 3. |  | 18.Hidenori Ishii |   Japan | 53.35s | NR | +2.96s | - | _ | 2.  |  | 23.Rui Abreu |   Portugal | 53.79s |   | +3.40s | - | 17 | 3. |   
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| Heat - |   | time |   | gap | L | ag | Rk  |  | 12.Bent Brask |   Norway | 52.79s |   | +2.40s | - | 20 |   |  | 15.Richard Burrell |   Great Britain | 53.09s |   | +2.70s | - | 19 |   |  | 19.Jorge Delgado Jr |   Ecuador | 53.43s | NR | +3.04s | - | 24 |   |  | 20.Miloslav Rolko |   Czechoslovakia | 53.49s | NR | +3.10s | - | 17 |   |  | 21.Nir Shamir |   Israel | 53.52s | NR | +3.13s | - | _ |   |  | 24.Jorge Fernandes |   Brazil | 53.90s |   | +3.51s | - | 16 |   |  | 25.Sergey Krasyuk |   Soviet Union | 53.95s |   | +3.56s | - | 16 |   |  | 26.Jose Pereira |   Portugal | 54.34s |   | +3.95s | - | 23 |   |  | 27.Juan Barro |   Spain | 54.36s |   | +3.97s | - | 21 |   |  | 28.Ali Gharbi |   Tunisia | 54.43s |   | +4.04s | - | 23 |   |  | 29.Hiroshi Sakamoto |   Japan | 54.45s |   | +4.06s | - | 18 |   |  | 30.Jasper Nordsted |   Denmark | 54.69s |   | +4.30s | - | _ |   |  | 31.Henrik Rasmussen |   Denmark | 54.79s |   | +4.40s | - | _ |   |  | 33.Kurt Dittrich |   Austria | 55.06s |   | +4.67s | - | 20 |   |  | 34.Marcus Mattioli |   Brazil | 55.27s |   | +4.88s | - | 17 |   |  | 35.David Cummins |   Ireland | 55.28s |   | +4.89s | - | 16 |   |  | 36.Ron Kehrmann |   Israel | 55.60s |   | +5.21s | - | _ |   |  | 37.Alfredo Mackliff |   Ecuador | 55.70s |   | +5.31s | - | _ |   |  | 38.Dariusz Broda |   Poland | 56.18s |   | +5.79s | - | _ |   |  | 39.Paul Rowe |   New Zealand | 57.00s |   | +6.61s | - | _ |   |  | 40.Zafer Atamar |   Turkey | 57.11s |   | +6.72s | - | _ |   |  | 41.Habib Soukni |   Tunisia | 57.64s | NR | +7.25s | - | _ |   |  | 42.Luki Niode |   Indonesia | 58.58s |   | +8.19s | - | 14 |   |  | 43.Edham Al-Seif |   Kuwait | 58.89s |   | +8.50s | - | _ |   |  | 44.Sallah Al-Berges |   Kuwait | 1:02.27 |   | +11.88s | - | _ |   |  | -. Frans Debets |   Netherlands | DNS |   | - | - | _ |   |  | -. Scott Newkirk |   US Virgin Islands | DNS |   | - | - | 17 |   |  | -. Barry Salisbury |   New Zealand | DNS |   | - | - | _ |   |  | -. Ari Wiren |   Finland | DNS |   | - | - | _ |   |   
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