If you’re using Razer Synapse look here:
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The math to determine the delay is fairly simple but for those interested here it is:
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This will get you to fire the AC/2s at nearly the max speed but it is still slower than group fire. Also, I've noticed that this somehow invokes the Ghost Heat that was recently introduced. Therefore, if you're on a hot map you can only get away with a few bursts before running the risk of overheat. With the ghost heat and this macro, overheating is a death sentence.
I have a feeling that since the macro is making it fire consistently, and under 0.5 seconds, the Ghost Heat is treating it as multiple simultaneous weapon fires so the heat scales dramatically.
To counter-act this, I've created a new 4x and 5x AC/2 delay. It basically introduces a 0.5s delay in between a max of 3 weapons to negate the Ghost Heat. In doing this, it makes your fire rate slower. This being said, I'd suggest simply running a Macro that only fires 2 or 3 weapons with a 0.5s delay between firing another 2/3 AC/2s.
If you want to maintain the Dakka in Razer Synapse, it looks like this:
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