primarily, the question is the weight of the fabric ... but was there a weight fabric regulation ?
Yes,
"
Specifications for Dark-blue Wool Shirting and Cape Lining Flannel To be fifty-four (54) inches, or 6/4 wide and to be made of pure long-staple American fleece wool, not less than one-half blood, free from shoddy, flocks, or other impurities, and to weigh not less than ten (10) ounces to the linear yard.
To be twilled and the nap very lightly slightly raised; to contain not less than fifty-six (56) threads of warp and fourty-eight (48) threads of filling in each square inch, and to be capable of sustaining a strain of not less than twenty-six (26) pounds to the inch in width of filling, tested in the piece.
The colors to be dark-blue...of the standard shades, and to be dyed with fast colors. The blue to be dyed in the wool with pure indigo.
Adopted June 10 1889..."