Please, get an SSD.
Lord Tachanka is insulted by your slow load times.
But SSDs are expensive
You can get a 500GB Samsung SSD on Amazon for $40 (on sale)
This will be plenty fast for Rainbow 6, and you can also fit a bunch more other games on here if you need.
This SSD should be compatible with most motherboards made after 2010. All you need is an open SATA port to be able to plug it in.
Make sure you have an extra SATA cable to actually plug this bad boy in.
Can I go even faster than an SSD?
Yes! Maybe? You'd need to check if your motherboard supports an NVMe drive, or in other words has an M.2 Slot.
If it does, then you can stick one of these awesome drives in it and load Rainbow 6 even faster!