Even without a chronograph, can figure some things out.

[Ribbonstone]

Sometimes , it is more fun to figure the sweet spot the no-chronograph-way. Got to accept the idea that velocity changes do change the point of impact on a target.  Low speed pellets land lower than higher speed pellets. 

But you can figure out where the best shots are in a fill even without a chronograph.  Won’t be exact, but will be close enough to be useful.

One fill
Identical targets
5 shots each
NO adjusting the scope
Even as little as 20-25 yards will work


Target doesn’t really tell you much at first:




But cutting out the groups, lining them up, and then connecting the groups does:




So by keeping track of the pressure while shooting these groups, can get an idea of where the sweet spot lives.


1. Takes a LOT of velocity change to make a ½” difference in point of impact at shorter ranges (25 yards).

2. This scope needed a bit of left, but once you start, adjusting the scope  in any way is a no-no.

3. While all 56 (counting that one “oops” shot) would have hit a paintball, which may be why such inflated shot counts seem common.

4. I do have a chronograph and the numbers match the target’s verdict.  There are only 20 really good shots in a fill with this rifle (although I could plink paintballs for 55-60 shots).

[jessered]

Brilliant!

[pelletman]

R,

Thanks for that very illustrative post..

It's pretty much the old H.I.T. (holes in target) method of PCP tuning I have used for years sans chrono..

It looks to me you might try reducing the fill pressure by about 10-20%... That will flatten the shot curve to the upper portion of those shoots..

As it is, I could shoot that rifle with the existing curve simply by compensation a bit in terms of elevation with regards to the first and last 10 shots of the string..

I do it with my Discovery all the time.

[thekid]

Excellent way to figure out the sweet spot and get in some trigger time.
Thanks for sharing this

[jessered]

Works perfectly.

Even at 10 yards you can see the curve.

I just drew a horizontal line on a piece of paper, held the scope on the line and moved over 2 mildots each shot.

[Motorhead]

Rocket science ... tell ya it's rocket science !!
Brilliant ... simply brilliant