Defiantly barred rocks.
Generally, I sex my barred rock chicks the day they hatch using a few methods.
Males are MUCH lighter, almost a gray color while the females tend to be very darker, almost black besides their white chest and white head spot. This isn't always 100% because sometimes females can be light like males(not as light though). However, I've bred BR for 10 years and never had a dark male.
When their wings Feather out you can usually sex them rather easily. Look at 2 of mine below and you can kinda see what to look for.
The first is a female at about 4 weeks. The second is a male also 4 weeks. Note how the male is almost evening white and black barred while the female is more black then white.
Post pictures at 4-5 weeks and I'm sure we can tell you exactly what you got <3
Males will generally be evenly barred because they carry 2 barring genes while the females only carry a single barring gene so they don't have as much barring.