If you lower the range, but at the same time you raise the number of samples, then you don't get a time reduction.
Try a scan from 76000 to 95000 with a step size of 20, and then another scan from 95000 to 114000 with a step size of 25. With these step sizes, you won't get holes. Anyway, It is better to have a less accurate scan than not to have a scan at all.
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