The shroud or flashhider counts toward barrel length if it is unable to be removed/permanent. i.e. welded, etc.
http://www.tacticalsol.com/products...age=flypage.tpl&product_id=199&category_id=12
Tactical Solutions AR-22 SB-X dedicated .22LR complete upper for an AR-15 offer a shorter length without the paperwork of an SBR. The AR-22 SB-X has an overall bore length of 12.25" but has an overall length of 16.5" due to the permanently attached shroud which will house up to a 1" outside diameter suppressor. SB-X Barrel is machined from 6061 T6 billet aluminum and have a barrel diameter of .920. A 1 in 16" twist chrome moly button rifled liner makes this an accurate and reliable choice for any shooter