I've got Mero on Android but can't get to the SLG0 drag table. Is it possible, or would need to extract from the desktop Windows app?
Here is the SLG0 reference drag law in its current form. It is based on an average calculated drag I created based on wind tunnel data.
Mach | SLG0 |
| (Cd.ref) |
0.000 | 0.210 |
0.045 | 0.205 |
0.089 | 0.201 |
0.134 | 0.198 |
0.179 | 0.195 |
0.223 | 0.194 |
0.268 | 0.193 |
0.313 | 0.194 |
0.357 | 0.197 |
0.402 | 0.200 |
0.446 | 0.204 |
0.491 | 0.208 |
0.536 | 0.212 |
0.580 | 0.217 |
0.625 | 0.222 |
0.670 | 0.227 |
0.714 | 0.234 |
0.759 | 0.240 |
0.804 | 0.246 |
0.848 | 0.252 |
0.893 | 0.269 |
0.938 | 0.323 |
0.982 | 0.453 |
1.027 | 0.614 |
Thank you for this! Do you have any idea how it compares, BC wise, to G1? Like, is there a ballpark I could start at to verify the dope?
Well I went and actually tried this... Problem is I don't see a way in the UI to add more rows to the table :/ Sigh... probably need to email the developer.
SLG0 is not really for round nose slugs, it was developed for slugs with large meplats. RA4 should be better unless they have a boattail where there is SLG1, though this is totally unproven, or, for very low drag designs, G7
Tell me how emailing worked on your machine, because on my droid tablet the Strelok 7.1.6 don't have any other option but only sink to dropbox. Yes, I had to make a dropbox account first and export up there to the clouds and then download to my PC... and now I don't have excell but OpenOffice thingies... ;(....from Strelok (emailed to my computer) — in order to edit them in Excel (or similar)...
What I really want: 
Something is off there, as wadcutter pellets have extremely poor ballistic coefficients.Miles,
I have a general question about how the cd values of the different drag laws relate to each other.
For example, cd (=drag) values at mach 0.8 — around 900fps — from several drag model in comparison — sorted from low cd to high cd:
0.2330 — RA4 (22LR bullet)
0.2362 — WC₀ (airgun wadcutter)
0.2411 — GA (airgun domes)
0.2460 — SLG₀ (airgun slug w/ meplat)
0.2546 — G1
0.6985 — GS (spherical round ball)
0.9303 — GC (plain cylinder)
In my ignorance I interpret this as follows:
Conclusion 🅐: "Of all of the listed reference projetiles, the 22LR bullet (of the RA4 drag model) has the lowest cd value (= the lowest absolute drag [at 900fps]).
"That means it has the least drop, and the least wind drift.
"In other words the most aerodynamical projectile of these (at 900fps) is the 22LR bullet."
Correct?
So far, so good.
Conclusion 🅑: "Wadcutters are second on the list and are therefore almost as aerodynamic as LR22 bullets — and have much less drag (at 900fps!) than a domed pellet or airgun slug."
Correct?
Conclusion 🅒: "Airgun domed pellets have less drag at 900fps than the G1 type bullet (pointed slug)."
Correct?
Conclusion 🅓: "The plain cylinder has an atrociously high drag — four times as high as a wadcutter.
"The drag seems so bad (so high!), it should almost be impossible to make a cylinder fly through the air, unless it was self-propelled by some engine/propellant."
"But... — JSB sells a flying cylinder (that admittedly has not totally straight walls but is wearing a mini-skirt) — and where a conscious tester measured a respectable BC (GA) of 0.022 and 0.027 (medium and high velocity, ChairGun, 31y, 50y, atmo incl., ). — So, against the terrible drag values of a cylinder, this cylinder seems to fly quite well...."
Mmmm.... —
It seems I'm reading something into the cd values that is not there....
View attachment 437744
A table and/or graph of absolute drag values — probably something I would need to test or calculate myself(?):
With that table/graph I want to compare the absolute drop & drift propensity of say, a .30cal 55gr dome, with a .25 26gr hollow point, with a .22 18.80gr wadcutter — at say 700fps and 900fps.
I'm sensing I'm missing an important factor here somewhere....
Help me out!
Matthias
MatthiasMiles,
I have a general question about how the cd values of the different drag laws relate to each other.
For example, cd (=drag) values at mach 0.8 — around 900fps — from several drag model in comparison — sorted from low cd to high cd:
0.2330 — RA4 (22LR bullet)
0.2362 — WC₀ (airgun wadcutter)
0.2411 — GA (airgun domes)
0.2460 — SLG₀ (airgun slug w/ meplat)
0.2546 — G1
0.6985 — GS (spherical round ball)
0.9303 — GC (plain cylinder)
In my ignorance I interpret this as follows:
Conclusion 🅐: "Of all of the listed reference projetiles, the 22LR bullet (of the RA4 drag model) has the lowest cd value (= the lowest absolute drag [at 900fps]).
"That means it has the least drop, and the least wind drift.
"In other words the most aerodynamical projectile of these (at 900fps) is the 22LR bullet."
Correct?
So far, so good.
Conclusion 🅑: "Wadcutters are second on the list and are therefore almost as aerodynamic as LR22 bullets — and have much less drag (at 900fps!) than a domed pellet or airgun slug."
Correct?
Conclusion 🅒: "Airgun domed pellets have less drag at 900fps than the G1 type bullet (pointed slug)."
Correct?
Conclusion 🅓: "The plain cylinder has an atrociously high drag — four times as high as a wadcutter.
"The drag seems so bad (so high!), it should almost be impossible to make a cylinder fly through the air, unless it was self-propelled by some engine/propellant."
"But... — JSB sells a flying cylinder (that admittedly has not totally straight walls but is wearing a mini-skirt) — and where a conscious tester measured a respectable BC (GA) of 0.022 and 0.027 (medium and high velocity, ChairGun, 31y, 50y, atmo incl., ). — So, against the terrible drag values of a cylinder, this cylinder seems to fly quite well...."
Mmmm.... —
It seems I'm reading something into the cd values that is not there....
View attachment 437744
A table and/or graph of absolute drag values — probably something I would need to test or calculate myself(?):
With that table/graph I want to compare the absolute drop & drift propensity of say, a .30cal 55gr dome, with a .25 26gr hollow point, with a .22 18.80gr wadcutter — at say 700fps and 900fps.
I'm sensing I'm missing an important factor here somewhere....
Help me out!
Matthias
Go to tools, select custom table columns, and then go down the list to Ref.Cd, select it and accept. Then select tables as your output as opposed to Reticle etc. I think that should do it
