Fortunately, I'm able to definitively say that the issue is not the Arduino because I can run a program on the Arduinos and have them communicate effectively at these high baud rates by jumper cable.
@Robin 2, that's true. While unlikely,
What methods would you recommend in checking the baud rate the Arduinos are running at?
Additionally, does anyone have any insight into why the HC-05 modules may not be running at their advertised baud rates?
I suspect the Arduinos are correct for the following reasons:I've tried making a Serial connection between the two Arduinos via Jumper Cables with at least 6 different baud rates. Each of them worked successfully. Therefore, I can assume that the Arduinos can handle various baud rates including baud rates well above the 480600.
I've also managed to create a Serial connection between the two Arduinos through the HC05s at various baud rates, but none above 115200.
You are not thinking about this logically. What you are doing is the equivalent of watching two german speakers communicating perfectly and then wondering why one of them cannot talk to a french speaker.
To my mind that is further evidence for the problem being on the Arduino - over that speed the error becomes unacceptable.
Have you carefully studied the Atmega 328 datasheet?
As I don't have your equipment to test I am not claiming to be 100% correct but let's wait to see if any other experienced Forum user disagrees with my analysis.
Do you understand the Scotsmen / Somerset men analogy?
I understand the idea of two devices that don't speak the same language having trouble communicating with one another.