The 17-lb LT-Gun weight limit gets hard to make when the barrels are longer.
Dependent on action/stock/scope, but typically much over 29" or so, weight can become and issue with the normal HV counter barrels that get used in LR-BR, that then fluting or special contours are needed. Plus there is balance issues to consider.
32" barrel, like Mike recommend is doable, but only from a VERY light build and scope, and/or with a special contour or fluted barrel.
For HV-Gun barrel length is not an issue, since there is no weight limit.
My 2-cents
Donovan