I am going to assume that you are talking about bottle neck brass. It can make a difference in accuracy depending on what you are loading for. For hunting rounds, I really don't think that you will be able to tell the difference though. In benchrest, probably.
Different manufactures brass can and will have differing thicknesses causing a difference in volume. Your brass may be trimmed to the same length but brass with a thicker head and body walls will leave you less room for powder and will cause a different pressure than brass with thinner heads and walls. Try weighing some from different haedstamps and see what you come up with.
I like some brass, hate others; certain brands I never have any problems with and lasts a long time; like Lapua & SSA. I just bought a couple thou of Starline, have to see, hear that people like it. No joke, I have Lapua 30-378 brass that has been reloaded 7-8 times and it's good; close to 98 grains of RL-22 too.