I would agree with Nik-Elas that it should be 77.7 shots / minute, but game could calculate it differently. I would assume a reload buff increases the normal reload speed such that 100% reload buff would make you fire 2x as fast.

Shots / Minute x (1 + Reload Buff) = New Shots / Minute

*or*

Seconds / Shot = (60 Seconds / Shots / Minute)

To add a reload buff, you multiply each side of the equation by (1/(1+reload buff))

So with a reload increase of 11%, you would multiply both sides of the equation by (1/1.11)

In your example:

70 x (1+0.11) = 77.7 shots / min

*or*

60 Seconds / 70 shots / minute = 1 shot / 0.857143 seconds

0.857143 * (1/1.11) = 1 shot / 0.772201 seconds

For your example of 60 shots / minute with 100% reload buff:

60 x (1 + 100%) = 120 shots / min

However, there are other ways which MA could conceivably calculate reload speed buff.