Adam's revolver has a plugged barrel, revealing it is actually a starter pistol that only fires blanks.
Lewis thinks it's not a coincidence that their murder victim was shot with a copper jacketed bullet from a .38 Special and his brother also owns a .38 Special loaded with copper jacketed bullets. However that isn't even close to being a coincidence, 98% of bullets have a copper jacket and a lead core. The only bullets that don't have a copper jacket are pure lead bullets, but those are only used in certain .22 Rimfire loads and in antique black powder guns and their replicas; armor piercing bullets have a steel or tungsten jacket, but those are only made for rifles and are illegal for civilians to possess. Pretty much all ammo for the .38 Special uses a copper jacket, plus both brothers having a .38 Special doesn't prove anything either. The .38 Special is by far the most common revolver in the world, statistically speaking most of the revolvers in Baltimore are going to be .38 Specials loaded with copper jacketed bullets.