Groups, some good, some bad, why? Also, first shots with JSB Hades!

I took the .25 Crown Continuum MKII out and shot some 50 and 75 yard groups with JSB Kings. As seen in the pics, the 50 yard groups look pretty good, a couple can be completely covered with a dime. Then it goes to 75 yards and they look like they seem to open up quite a bit more than I'd expect. Conditions pretty decent, in between the calm there were some 5 to 10 mph gusts, but still I feel like the groups should not be opening up that much at only another 25 yards. They look like they should be 100 yard groups.

Also, I shot some JSB Hades for the first time. The first group was on the same setting as the Kings, then I turned the hammer spring down one notch and the groups tightened up considerably. I must say I'm pretty impressed and look forward to playing with these some more.

Anyway, thoughts on why the 75 yard groups open up so much?

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75 yard groups. The piece of cardboard near the second group is covering a couple of errant shots from the next group over. Both groups are 10 shots

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Pellets are just very susceptible to wind. They're quite tricky to shoot with real precision that far out.

Also looks like there may be some improvement to be found in your tune. I'm not %100 sure. That would really depend on how steady your gun was when you were shooting. I'd try and make a small pressure increase to the regulator, or make a small adjustment to the hammer tension and shoot another group. See if they tighten any. If you've been shooting a lot, check the bore for lead shavings, might could use a clean.

I know my crown with the 380mm pellet liner A will shoot hades thru damn near the same hole at 40 yards on a calm day. But of course there is user error. But overall I've found the Crown to be an extremely forgiving platform as far as technique (or lack of) goes.
 
Pellets are just very susceptible to wind. They're quite tricky to shoot with real precision that far out.

Also looks like there may be some improvement to be found in your tune. I'm not %100 sure. That would really depend on how steady your gun was when you were shooting. I'd try and make a small pressure increase to the regulator, or make a small adjustment to the hammer tension and shoot another group. See if they tighten any. If you've been shooting a lot, check the bore for lead shavings, might could use a clean.

I know my crown with the 380mm pellet liner A will shoot hades thru damn near the same hole at 40 yards on a calm day. But of course there is user error. But overall I've found the Crown to be an extremely forgiving platform as far as technique (or lack of) goes.

All good points, I'm going to play with the tune some more. I played with it just enough to find that I can get back to my current tune without much difficulty should things go south.

I def need a more stable bench, anyone would laugh at the bench I was shooting the 75 yard groups from. 50 yard groups are from a marginally better bench. Will be building a new one shortly.

Also, you're right, it's been a while since I've cleaned the barrel. Just don't think about it so much since the FX barrels seem to get so many shot between cleanings. 



Did you measure the wind ?

Hmm... I don't really have anything to measure the wind other than my weather app which said the wind in the area would average 8mph at the time I was shooting, but a good portion of the shooting was done when there was no wind. I suppose that could contribute to the 75 yard groups opening up. I remember reading that even if I can't feel wind where I am at it doesn't mean there isn't wind further along the pellets flight path.
 
If you are able, put a wind indicator in the ground at your range. I use a three foot rod with a two foot ribbon attached to this. It isn't scientific, but it will help you judge wind speed relative to the ribbon's angle and the appropriate holdovers. You will be surprised at what a crosswind versus a headwind will do to a pellet. 

Those Hades are nice, but due to the three holes in them I can see the groups opening up a little bit with a variable wind.
 
All good points, I'm going to play with the tune some more. I played with it just enough to find that I can get back to my current tune without much difficulty should things go south.

I def need a more stable bench, anyone would laugh at the bench I was shooting the 75 yard groups from. 50 yard groups are from a marginally better bench. Will be building a new one shortly.

Also, you're right, it's been a while since I've cleaned the barrel. Just don't think about it so much since the FX barrels seem to get so many shot between cleanings.



👍

A half-way decent table and a sandbag should cut it. But a good excuse for a new project :)

I noticed my superior liner has not really seemed to need any cleaning yet.... And I cant recall if I polished it or not.... I don't think I did? At any rate, my short 380mm pellet A used to get fouled up pretty good after 2-300 shots, but I did polish it, and that helped some. I went and de-greased it. Then used pure carnauba wax in the bore, and I have not had to clean it in ages without the accuracy degrading.... But for sure my slug A barrel still fouls up really bad, but may be due to the slugs.... At any rate, what I'm getting as is there are some things that can alleviate the clean interval, if there is one. But also, it may not be needed, but worth a look still. 

Good luck :)


 
A 5-10mph wind is an absolute group killer at 75 and beyond. Don’t look for a problem with your tune until you have poor groups in completely calm conditions. And I mean dead calm. Your groups are realistic groups.

Good point, I should wait until I have a totally calm day before making other assumptions, thank you for the feedback! Cliff
 
I have wind indicators (yarn on a stick) at my targets and at the end of my barrel. In many instances the wind is blowing in different directions at the bench and target. This makes grouping in those conditions almost impossible. Also while 75 yards doesn't sound like a big increase in yardage over 50 yards, it is quite an increase. Anyway good shooting and observations.
 
Finally the wind stopped. For like a red hot minute. I ran outside to try some 75 yard groups. The following pics are the first 10 shot group. I went to go look at the target and on my way back the dang breeze picked up again out of nowhere and I could not replicate the results which frustrates. I like to see a great group but like even more to be able to repeat for confirmation. However, I feel optimistic my issues lay with the environment and not with the capabilities of the gun.

Also, it is freezing here and I noticed it affects the working pressure of my regulator. The pressure seems to drop some and I can only image this affects the "tune" or the harmonics of the gun? It seems my groups widen up the longer the gun is outside. Anyone know if this hypothesis is based in fact?

Thanks again for all the help and suggestions!

Cliff



I'm pretty tickled with this group even though it's the only good 10 shot group I've been able to muster at 75, it is still 10 shots with only the one flier. Now if I can just get one day that is completely calm and not freezing out to see if it is repeatable. 

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If you are able, put a wind indicator in the ground at your range. I use a three foot rod with a two foot ribbon attached to this. It isn't scientific, but it will help you judge wind speed relative to the ribbon's angle and the appropriate holdovers. You will be surprised at what a crosswind versus a headwind will do to a pellet. 

Those Hades are nice, but due to the three holes in them I can see the groups opening up a little bit with a variable wind.

The wind that ruins a 50+ yard group is so slight you can't even feel it.
Just once try yarn on posts every 10 yards and it will likely be moving even when you sense NO WIND.
 
If you are able, put a wind indicator in the ground at your range. I use a three foot rod with a two foot ribbon attached to this. It isn't scientific, but it will help you judge wind speed relative to the ribbon's angle and the appropriate holdovers. You will be surprised at what a crosswind versus a headwind will do to a pellet. 

Those Hades are nice, but due to the three holes in them I can see the groups opening up a little bit with a variable wind.

The wind that ruins a 50+ yard group is so slight you can't even feel it.
Just once try yarn on posts every 10 yards and it will likely be moving even when you sense NO WIND.

Agree 100%. And terrain can create eddies and swirls in wind even across a 50 yard distance.
 
If you are able, put a wind indicator in the ground at your range. I use a three foot rod with a two foot ribbon attached to this. It isn't scientific, but it will help you judge wind speed relative to the ribbon's angle and the appropriate holdovers. You will be surprised at what a crosswind versus a headwind will do to a pellet. 

Those Hades are nice, but due to the three holes in them I can see the groups opening up a little bit with a variable wind.

The wind that ruins a 50+ yard group is so slight you can't even feel it.
Just once try yarn on posts every 10 yards and it will likely be moving even when you sense NO WIND.

You're right. I hung a ribbon out, it was only about 15 feet away from me and it was being pushed slightly sideways even when I could feel no wind at all. 


 
Everyone knows that wind will mess with even the best of shooters. Was at a fun shoot a few years back and had a ribbon on a post about 25 yards from me but was shooting at a target at 50, the ribbon was showing I needed to hold off left but the group was saying I needed to hold right, two different wind directions withing 25 yards of each other. This would have been noticeable with a second ribbon at the target but without it, it was really messing with my mind until I sorted it out. It's no surprise extreme benchrest uses flags all the way to the target.