It makes naff all difference. Andras's tests and others show lock time on pcps is in the order of 3-4ms for the fastest to perhaps 8 for the slowest. Even springers have it in low teens.
Now that's .003 of a second at best or .008 at worst for pcps. Putting that into perspective the human reaction time is around 0.4 of a second. Ie 10x slower. So even with the fastest and slowest your lock time is insignificant to your brain's ability to react to a response to input. Not only that but in addition there's all sorts of things the brain plays tricks with using the eyes as well.
Why guns feel faster than others I believe is due to the recoil and vibration through the shot cycle. Ones with less tend to feel faster especially when coupled with a crisp second stage break on the trigger.
You can with Scatt trainers measure the speed of wobble in the last moments of a shot being taken. Say with a bad stander that never settles and a ****** shot your looking at about 10cm in a second at 10-20 yds So say a gain of 3-4ms at best will see you reduce that by 0.3-4 of a millimetre. At say 40 0.6-8 mm. Your far better off working on what makes you wobble than buying a new gun that may shave less than 1/2 - 3/4 a mm off a real bad wobble.
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