He was registered as a sorrel pinto when born but l've been told by some thats wrong he's a chestnut not sorrel l'm putting him into the R shortly and would like to know the correct color to put down for him...

That is how I was taught as well, years ago by an old (93year old) Calvary soldier who owned and taught at a large academy in Michigan!Today in many breeds the terms are interchanged. Sorrel used to mean shades of red body with mane and tail lighter colored than the body. Chestnut was also a red body but the mane and tail were the same color as the body.
That's pretty much how I learned the "difference". I used to own a Chestnut AQHA mare and her son is a sorrel. The mare was rather dark with dark mane and tail; he's somewhat pale with nearly flaxen mane and tail.Sorrel - Red with lighter mane and tail than bodyToday in many breeds the terms are interchanged. Sorrel used to mean shades of red body with mane and tail lighter colored than the body. Chestnut was also a red body but the mane and tail were the same color as the body.
Chestnut - Red with mane and tail same color red as body
So My 2 cents worth... he is Sorrel :0)
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