Pellet speed H&N 5.5mm

I see it is a app you developed, so that is why you promote it. ;)
I had nothing to do with its development or the software that was done by the late George Conway. All I have ever done is provide some suggested drag laws, but again I have had no input into the GA drag law, that was in the original Chairgun. The original developer of Chairgun now looks after the MERO software since its original developer sadly passed away late last year.
 
I had nothing to do with its development or the software that was done by the late George Conway. All I have ever done is provide some suggested drag laws, but again I have had no input into the GA drag law, that was in the original Chairgun. The original developer of Chairgun now looks after the MERO software since its original developer sadly passed away late last year.
OK.

I Played with MERO a bit. I see the results does not differ much from Strelok results. But as I concluded before, the difference between app and real must be because of barrel harmonics.

In the MERO app, a few things I see.
* If I change the far zero, the killzone size automatically change to something else than my input. If I then change the killzone input, the far zero change so something else than my input.
* Is there a way to have MRad per click instead of MoA per click?

Maybe there is a few other things I will struggle with as well. 🤷‍♂️
 
Know your limits . don't you take a few sight in's b4 you hunt ?
Will the pigeon always be at the distance you sight in your rifle?
OR
Calibrate your ballistics app to what your rifle is doing and have dial / holdover results whatever the distance of your target. If you don't want to use your phone while hunting, write or print a cheat sheet with the correct dope or from the app. It gets to the same results.
 
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I know what my rifles and I are capable of, that is why I use the app. There are guys shooting pigeon with pcp at 150 meter and more. Knowing the holdover for every distance from nearby to that far is not many people in the world that can do that. With my pcp I limit myself to 50 meter but if the wind is still and the target well placed, I will take up to 75 meter shots. With my .22LR my normal limit is 100 meter but will stretch it to 150 meter on a pigeon in the right conditions. Maybe I am just plain dumb but I cannot remember the holdover for each rifle for each distance in-between.
 
In the MERO app, a few things I see.
* If I change the far zero, the killzone size automatically change to something else than my input. If I then change the killzone input, the far zero change so something else than my input.
* Is there a way to have MRad per click instead of MoA per click?

Maybe there is a few other things I will struggle with as well. 🤷‍♂️
There used to be an email address on the GPC website where you could ask questions and George would either explain how to do it if possible or incorporate changes into future versions of the software. I am not sure if the email is still there since George passed away.
 
Follow up.

I am playing with different things to see what it does to accuracy. I saw Gary Chillingworth on Shooting & Country TV channel have a bunch of weights on his one AA springer rifle to improve accuracy, so he says.

I put a piece of leather between my rifle's barrel shroud and the air tube and then tightly taped a bunch of mag wheel weights to it. I had to re-zero the rifle at 50 meter. Then adjusted 3.5 MRad up as always to shoot at the 100 meter target. The pellet missed the plate low. I then adjusted higher and higher to be about on target. The turret setting ended at 4.2 MRad to be close to POA, closer to the setting given by Strelok with the BC given by H&N. However, I still had to adjust the BC in Strelok to about .038, not precise. It is also known that a projectile's BC alters with speed, so I still don't know what the correct value must be.

As well as what Matt showed about JSB pellets in his video previously linked in the thread.

Ted from the channel Teds HoldOver also found different POI with increase of speed with his FX and slugs. He also at first concluded that the BC increased but in the comments and elsewhere here on AGN is was concluded that it was barrel harmonics causing the different POI and not the BC per se. I don't know what Ted's final conclusion was after the video and comments. Video below.

My conclusion is that it happens because the barrel is now stiff with all the weight and tape and don't move as much causing it to have a different POI. Without the weights the 3.5 MRad setting can only be because of barrel harmonics causing the pellet to shoot higher than what Strelok is calculating and I had to compensate on the turrets for it by dialing less MRad upwards.

The problems with the extra weigh is that the group open up a lot and that the rifle is now heavier and uncomfortable to carry in the field if I want to. So, knowing this I removed the weights and leather again. The leather was to prevent the tape to close the gap between barrel and tube. The thing is that I don't know if there is a way to compensate for it in Strelok other than adjusting the BC as I did before.

Another question, will a barrel tuner correct the harmonics to:
(1) Bring the dial setting to what it must be?
and /or
(2) Will a barrel tuner improve accuracy?
Both that questions I can only know the answer to if I buy and install a barrel tuner and test it. I did see it improving accuracy on a FX in a video as below from Airbuks


Video from Teds HoldOver:



Video from Airbuks:

I can't remember right off top but something I picked up from a pioneer in airguns and airgun building world.he said the first thing he does is make sure your turrets are zeroed in both directions and would shoot a group and if the poi was off more than just a few clicks could compensate for he would take the liner and would bend and bring the poi to be close to the POA while the scope was a mechanical zero and would go from there .it sounds crazy at first but it makes all the difference.now keep in mind when I say bend it's more like massage the liner in the right direction
 
I can't remember right off top but something I picked up from a pioneer in airguns and airgun building world.he said the first thing he does is make sure your turrets are zeroed in both directions and would shoot a group and if the poi was off more than just a few clicks could compensate for he would take the liner and would bend and bring the poi to be close to the POA while the scope was a mechanical zero and would go from there .it sounds crazy at first but it makes all the difference.now keep in mind when I say bend it's more like massage the liner in the right direction
 
I have uploaded the MERO app and it's pretty good. Of course not the same as Strelok, takes a little getting used to it, but pretty good overall.
Comparing it to Strelok, I noted yesterday that a 126 yard shot showed 5.1 MIL (51 clicks). This was incorrect as I missed my target low. I found a small, .5" pebble to shoot at that range and found that it should have been 5.4 (I ultimately got my target at that setting).
MERO spit out 5.4 MIL, so spot on, after checking that everything was identically input. I like it, although it does show MOA, all of the information for MOA and MIL are within the Target Distance Box, so no biggie.
Thanks BB for the information!
Mike
 
I played again with the MERO app. I understand now why Far Zero and Killzone change if I change the other. It was just me having a blond moment for thinking it should not. When setting zero distance, it will have a fixed killzone as it takes the maximum trajectory height and multiply it by 2, that is the diameter of the killzone. If you enter a killzone diameter, it does the reverse of the calculation and calculate what distance will apply to that and change the far zero accordingly. I knew it but because Strelok have a separate page for MPBR and you have to change the resulting recommended zero manually, I did not think of it the other way that MERO is doing it.
 
Here is some videos using Strelok and Applied Ballistics. Both can be connected to a Kestrel unit. He explained in the Kestrel / Applied Ballistics video how to adjust for different trajectories and said Strelok cannot do it. But actually Strelok can do is by entering different BC values in the multiBC window. I did it with my .308 some time ago but one day still need to do it with my .22LR.




 

Alan zasadna
Nice video about an interesting guy.

About 2 years ago I did bend the barrel on my Gamo Magnum as the POI was to the left and I had to adjust a lot on the open sights to get it to zero. It then helped with zeroing the scope without to much adjustment as well. I want both the open sights and the scope to be more or less zeroed for if something goes wrong with the scope that I can still use open sights.
 
I made some changes to the rifle. I had a Gamo RRR I took off the Gamo rifle. (Recoil Reducing Rail, doing nothing in that regard) I put onto the M22 and the scope on top of that. It raised the scope by 12mm and now the scope height is 52mm. According to Strelok it changed the mrad I had to dial by 1/10 of a mrad less. Then the other day I did this as well :


When shooting that group I had to dial at 3.2 mrad for 100 meter, even less than the 1/10 calculated. The next morning in the cool it shot a bit low on that setting but then in the afternoon in the 27 deg C it shot spot on at the 3.2 mrad dial.

Again, it just show us that barrel harmonics has a lot to do with the actual POI compared to what calculators suggest to do.
 
I ordered 10 tins of Rifle Premium Round 18.67 grain pellets and received it today. I did try to source it locally but no shop had it and is not willing to order any. Their loss. I now have a wider selection of 5.5mm pellets than all the local shops combined.

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According to their website the above specs. They say BC of .023 and 50 meter maximum. Ja-right, as if I am going to limit it to 50 meter.

Anyway, I just shot a few at 50, 75 and 100 meter. First I checked the velocity and it was around 960fps instead of the 940fps the H&N did so, I reduced it to 940fps. The pcp was zeroed for the H&N Baracuda 18 pellets so the POI was low and left. After re-zeroing the groups at 50m were good, the same as the H&N. Then at 75m I had to elevate it more, 2.3 MRad instead of the 1.5MRad for the H&N. Groups were good. The to the 100m gong. Had to adjust to 4.7MRad instead of the 3.2MRad of the H&N.

Then I adjusted Strelok for it. Strelok data also have the BC as .023, presumably taken from the website. If I adjust the BC to match the 100m it must be .024 but then it show 2.0 MRad for 75m. If I adjust the BC for 75m it must be .019 but then it shows 5.5 MRad for 100m. So I must then enter multi-BC to correct for both distances. Without a radar chronograph it seems impossible to have the correct multi-BC values for all distances. It looks like it is starting with a low BC as given and then increase a lot as the speed decrease.

It seems to be a nice shooting pellet but how do I correct the data in Strelok for the various distances?
 
How do I correct the data in Strelok for the various distances?


I think you're doing great already! 😊

I am on the same journey as you — trying to get Strelok to line up with non-conventional pellets, and non-conventional velocities and ranges:
E.g.: shooting hollow points (that don't fit any of the current drag profiles) — at velocities over 900fps (where the certainly will have a different drag coefficient than the dome that the GA model uses as their base projectile.


I am only a few weeks away from trying what I will suggest to you here:
🔶 If you can, measure the velocities with a chrony at several different ranges (10-15 shot averages), especially where the projectile is flying at high velocities close to you, maybe: 0m — 15m — 30m — 60m — 100m.


🔶 Measuring actual velocities is more precise than measuring projectile drop (because the barrel oscillations [barrel harmonics] can falsify true drop values). But better drop than nothing. 😆


🔶 Then, using trial and error, enter variable BC numbers into Strelok until the Strelok values match up what you measured in your tests (velocity, or drop).
Instead of 5 variable BC numbers, Strelok also allows you to enter a custom drag model that allows for finer adjustments.



Let's see what Ballisticboy says — what a privilege to have him here at AGN. ⭐

Cheers,

Matthias