30 shot string
Ok a quick note on the string below. We took our scuba tanks to the dive shop to be topped off, we went back two hours later and topped off our gun tanks in the store and then they topped off the scuba tanks once more. In the store I had a full 3K fill in my gun tank at between 65-70 degrees. Out where I did the string it was 50-60 degrees, so take that into consideration. Ok here goes…Starting pressure in between 2900-3000/21.1 Gr. .22 Cal. Beeman Kodiaks/24″ inch barrel/Hi-flo valve.
1. 1040
2. 1068
3. 1065—–Low=1040
4. 1060—–High=1078
5. 1073——Avg=1069
6. 1078—–E.S.=38.20
7. 1073—–S.D.=11.53
8. 1077
9. 1075
10.1076
11. 1078
12. 1071
13. 1073—–Low=1041
14. 1070—–High=1078
15. 1066——Avg=1062
16. 1065——E.S.=37.06
17. 1055——S.D.=12.60
18. 1056
19. 1043
20. 1041
21. 1041
22. 1032
23. 1024——Low=987.5
24. 1021——High=1041
25. 1019——-Avg=1013
26. 1010——-E.S.=53.59
27. 1008——-S.D.=17.37
28. 996.0
29. 994.5
30. 987.5
Well what do you think?
All Replies
Can you get a tighter SD from a Hi-Flow valve?
In actual fact, someone posted not long ago with an SD of about 9….
If you want 30 flat shots with Kodiaks, my initial tuning advise will be different than if you want 20 max power shots or 15 max power shots…
For 15 I’d say leave it alone!
Jerry, I’m sold on the 21.1 Kods. for my gun. I’d like 40 shots from 900 to 950 and back. Or should I try to get closer to the 1K mark? EDIT: Jeff I didn’t check ending pressure sorry. How close to the speed of sound (1116 FPS, I know, it varies) is TOO close???
I was ignoring the first shot and looking at the next 15 as the string. That set is pretty nice. If you want 30 that flat you’re going to have to back it off a bit. It really makes sense to decide clearly on the objective before you make anymore adjustments though. I’d also decide on the pellet of choice too as that will influence the outcome.
If you want 30 flat shots with Kodiaks, my initial tuning advise will be different than if you want 20 max power shots or 15 max power shots…
For 15 I’d say leave it alone!
So at most you have -3.4% psi loss. 3,000×3.4%=102=2898psi
So if I understand your math, your saying .17%X20 degrees=102Psi.???
Sorry I left out the first part. .17%x20degrees=3.4% then 3.4%x3,000=102psi
Edit: What was the end fill pressure?
So at most you have -3.4% psi loss. 3,000×3.4%=102=2898psi
So if I understand your math, your saying .17%X20 degrees=102Psi.???
I did a little test last week to see how much temp. differences effect tank fill pressure and I got .17%+/- per degree change. This is from my testing, you may get different results but it should be close.
So at most you have -3.4% psi loss. 3,000×3.4%=102=2898psi
One other thing I didn’t do that I’ve read your supposed to do is throw away the VERY (shot #1 in the first string) first shot after a fill. If weather permits I’ll shoot again today.
If you get no poi change, then its good enough. But I know where you are coming from. I would be wanting to tighten it up too.
What would make you happy? Not being cute but you’ve got at least a 15 shot really tight string that would be good for target shooting or hunting. Are you looking for higher power? That will clearly reduce the shot count and you probably can’t add enough pressure to get a string that doesn’t fall off pretty fast with the current configuration. If you’re looking for a longer flat string, you’re going to have to reduce the velocity a good bit and drop the pressure in conjunction with the lower settings.
I don’t think your being cute, I appreciate yours and Pabs. (and others too please) opinions. I am more than happy with the velocity, I’d like to see some more efficiency. I don’t see any point in going faster than what I’m doing, in fact, probably should try to slow it down a bit. I have the p.w. set between 10 and 11 and 5 on the kno Maybe I should back it off to 5 or somewhere in between 5 and 10 and do the string again. My top hat is at .069″ Advise please…
What would make you happy? Not being cute but you’ve got at least a 15 shot really tight string that would be good for target shooting or hunting. Are you looking for higher power? That will clearly reduce the shot count and you probably can’t add enough pressure to get a string that doesn’t fall off pretty fast with the current configuration. If you’re looking for a longer flat string, you’re going to have to reduce the velocity a good bit and drop the pressure in conjunction with the lower settings.
Edit on above * Yeah, actually, you are right ‘sam , I wouldn’t be exactly over the moon with those, but I’m on a Blod valve which gives me about an sd of 6 day to day, about 4 after a fresh clean and lube…
I don’t think there’s enough. I was comparing it to 80G’s string (which may be pointless) But I need to do some more strings when it’s not so cold.
How does it compare to one of your better strings then?
Is the deviation between shots enough to make poi difference?
Edit* Yeah, actually, you are right ‘sam , I wouldn’t be exactly over the moon with those, but I’m on a Blod valve which gives me about an sd of 6 day to day, about 4 after a fresh clean and lube…
N/T
- You must be logged in to reply to this topic.
I don’t know Pab. Maybe I should shut up and be happy???