These are compiled arm length results for OT taken in the 2013 draft. You can see in this limited sample that the Offensive Tackle drafted in round 1-3 have a 34"+ arm length, on average.
|2nd & 3rd Round||OT||34||34||34|
|4th & 5th Round||OT||33.77||33.375||34|
|6th & 7th Round||OT||33.5||32.625||34.375|
The Offensive Guards have shorter arm lengths than the Tackles, but arm lengths are still very important. When the talent decreases below the 3rd round, NFL teams default to guards with longer arms.
|2nd & 3rd Round||OG||33.4||32.75||34.125|
|4th & 5th Round||OG||34.33||34||34.875|
|6th & 7th Round||OG||34||32.25||35.5|
The Center position clearly has less to do with arm length than it has to do with athleticism.
|2nd & 3rd Round||C||N/A||N/A||N/A|
|4th & 5th Round||C||33.5||32||35|
|6th & 7th Round||C||33.5||33.5||33.5|