The generator matrix

 1  0  1  1  1  1  1  1  1  1  1  0  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  7  1  1 21  1  1  1  1 42  1  1  1  1  1 21  1  1  1  7
 0  1  1 31 16 48  4 19  0 36 31  1 16 19  7  7 14  9  9 23 23 14 36 29  8  1 26 40 40  5 12 12  4 48 46  1  6 38  1 20 38 46 17  1 41 11 45  6 32  1 17 20 32  1
 0  0 35 21 42  7 14 21  7 28 14  7 35  0 28 42 14 21  0  7 28 21 14 42  7 21 35 28 42 35  0 21  7 28  0 42 35 35 21 14  0 21  7 28 42 35 42  0 28 35 28 21 42 14

generates a code of length 54 over Z49 who´s minimum homogenous weight is 315.

Homogenous weight enumerator: w(x)=1x^0+72x^315+1890x^316+3528x^317+1050x^318+108x^322+1512x^323+1176x^324+252x^325+120x^329+2772x^330+3528x^331+756x^332+36x^336+6x^350

The gray image is a code over GF(7) with n=378, k=5 and d=315.
This code was found by Heurico 1.16 in 4.74 seconds.