I suspect some of you guys may have seen this effect, but I thought I'd share some measurements that seem to be shaping up into a hard to ignore pattern. Please confirm or refute if you have an opinion/data.
So, I got a new tin of pellets (14.35) to try out on my .22 FX Indy. As usual, I first crony the pellets to make sure they are consistent, and only then move to accuracy tests on the range (if crony results are bad, I don't bother with the range at all).
The pellets performed well, but that's not the point. I noticed something interesting. If I keep the gun cocked for a somewhat extended period of time, say 10 min, I almost invariably get a noticeably slower reading on the chrony.
For example, if I keep the hammer un-cocked while changing the magazines and pumping up the gun (Indy is a pumper, as you know), and take a shot very quickly after putting the magazine in, my first shot in a string is indistinguishable from the rest (6 shots at power setting 2 starting at 192 or so bar), as long as I shoot at a fairly rapid clip, say 5-10 sec or so between shots. If, however, I keep the hammer cocked while loading the mag/pumping/taking a break to take notes, etc, the first shot is almost invariably 1-2% slower than the rest of the string.
Here is an example (just one, its an easy to reproduce pattern)
708 <--- cocked 10 min before shooting, the rest are shot quickly one after another
716
718
719
716
721
No break
718 <---- cocked just before shooting
716
721
714
715
719
The effect is small, of course, but I still found it curious. Is hammer spring getting 'tired' a bit over the course of several minutes?
So, I got a new tin of pellets (14.35) to try out on my .22 FX Indy. As usual, I first crony the pellets to make sure they are consistent, and only then move to accuracy tests on the range (if crony results are bad, I don't bother with the range at all).
The pellets performed well, but that's not the point. I noticed something interesting. If I keep the gun cocked for a somewhat extended period of time, say 10 min, I almost invariably get a noticeably slower reading on the chrony.
For example, if I keep the hammer un-cocked while changing the magazines and pumping up the gun (Indy is a pumper, as you know), and take a shot very quickly after putting the magazine in, my first shot in a string is indistinguishable from the rest (6 shots at power setting 2 starting at 192 or so bar), as long as I shoot at a fairly rapid clip, say 5-10 sec or so between shots. If, however, I keep the hammer cocked while loading the mag/pumping/taking a break to take notes, etc, the first shot is almost invariably 1-2% slower than the rest of the string.
Here is an example (just one, its an easy to reproduce pattern)
708 <--- cocked 10 min before shooting, the rest are shot quickly one after another
716
718
719
716
721
No break
718 <---- cocked just before shooting
716
721
714
715
719
The effect is small, of course, but I still found it curious. Is hammer spring getting 'tired' a bit over the course of several minutes?
