Yes, since this one has a heavy barrel it is legal in Maryland. Hope this helps

James, --- FYI, if you take the time to read my answer fully, S&W M&P SPORT II model 11616 is on the MD State Police APPROVED gun roster , go down to S&W, model 11616 -- Not Banned, Does not meet the definition of a copycat weapon or the definition of a copy of an enumerated weapon, 9/17/2021, Heavy Barrel Version >>>> https://mdsp.maryland.gov/Organization/Pages/CriminalInvestigationBureau/LicensingDivision/Firearms/FirearmSearch.aspx?Paged=TRUE&p_GroupCol1=Mossberg&PageFirstRow=101&&View={5E568F20-A495-4E49-A0E0-C53F530B98F7} .....HAPPY NEW YEAR!

Mikes, the Windham AR HBAR is MD legal. The S&W M&P Sport/Sport II is NOT MD legal. Details from a MD FFL Dealer here : blackanchorarmory.com/md-compliant-ars.html

Mike, yes, that one is on the MD gun roster. It has heavy barrel and is MD compliant. So is this M&P 15 Sport II >>> budsgunshop.com/product_info.php/products_id/23979/smith+&+wesson+11616+m&p15+sport+ii+semi-automatic+223+rem556+nato++16+10%2b1+6-position+black+stock+black ......check my answer to your first question, Happy New Year!