>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
COMPREHENSIVE BC Table .22cal
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Below are the introductory comments to a
comprehensive internet wide collection of ballistic coefficient data.
The table (1 page) and supporting evidence (50 pages) is found in a PDF document in my dropbox.
(I tried to condense the file size, but because of the photos of rebranded pellets the PDF is too large to attach in a forum post).
Link to the PDF file:
https://www.dropbox.com/s/dkf9174yr69igw4/BC%20Pellet%20Table.%20%20.22cal.%20%202018-10-02.%20%20V.125.pdf?dl=0
The heart of this 50-page article is the table on the second page – the pellet table – an overview of pellets with a relatively high ballistic coefficient (BC) (as published), with the following characteristics:
• .22 cal (5.5mm)
• High quality pellets (brands: JSB, H&N, RWS, Air Arms, Crosman)
• Usually available in the US
Often, main pellet manufacturers rebrand pellets, selling them under a different brand and sometimes with a different pellet name. There is some discussion whether these are the same pellets or different, and I tend to think that most of them are so similar that the BC will also be very similar. (Links are included in the section Rebranded Pellets below the table.)
The bottom part of the table includes a rebranding list, as rebranded pellets are not mentioned separately as to make the table more complicated yet. Note that sometimes the BC was measured using a rebranded pellet, this is noted in the table with the appropriate rebranding code, e.g., RB-F.
The BC values found in the literature vary, sometimes in frustrating extremes. Some are reports of actual tests, often with test conditions and calculation methods reported, others are simply lists of BC data without any information where these data were taken from.
Each BC values has a raised number after it12, sometimes a number and a letterA7. These refer to the source list of the BC data at the beginning of the table. More details about the BC data and internet links to them are included in the section Sources of BC Data at the end of this document (which also includes brands and calibers not found in the pellet table).
Each entry in the source list can consist of the following:
Author (Year-Month). Test -or- List. Ballistic Calculator used, Drag model used. Muzzle Energy (aprox.). Distance of second chronograph.
Examples:
0P H&N (2013-12). Test. 31FPE. 50y
2 ChairGun V 4.3.1. (2017). List. GA-model. Some data from the APP
4 ChronoConnect.com (2012 and Older). List
7B ASRA (2017). Test. ChairGun Calc, GA-Model. 32FPE. 31y
Sometimes concerns about the trustworthiness of the data are mentioned.
The difference between the published BC values has to do with many factors:
• The BC depends on the drag model used to calculate the BC. The currently best model is the GA model; many used the inferior G1 model; and the worst is a fixed drag model. The source list sometimes specifies which model was used. Also, some ballistic calculators are much more simplistic than the sophisticated, thus accurate ChairGun, cf.:
https://sites.google.com/site/scixddevexteriorballistics/
• The BC depends on the atmospheric conditions. Some calculators do not even allow entering atmospheric conditions, and some shooters might not have considered recording and entering this data.
• The BC depends on the velocity of the pellet (and the BC does not vary in any predictable way unless it reaches the speed of sound). The source list often specifies the muzzle energy used for the testing to give some indication how applicable the data is.
https://arxiv.org/pdf/1503.05504
Post #1 with G1 model, + Post #23 improved with GA model:
https://www.gatewaytoairguns.org/GTA/index.php?topic=14735.20
Bob Sterne (screen name rsterne, on the GTA forum and others), and to some extend Harry (aka Yrrah), have ventured into measuring BC data at different velocities (cf. his variable BC values for the JSB pellets in the above link). This is a very promising approach and goes beyond what this present list of published BC values accomplishes:
With a velocity-adjusted BC table, the shooter could select a BC appropriate for the muzzle velocity and intended distance to the target and use this more accurate BC for the ballistic calculations instead of a generic BC from a data base.
The ballistic calculator Strelok Pro (mobile app) is extremely powerful and allows the shooter to create new entries into its projectile data base. The shooter can enter various BC values for different velocities, or can enter the data for a completely new drag curve, specific for the pellet.
• The BC depends on the tester’s motivation:If the tester a manufacturer who wants to promote their pellets – then they might be motivated to experiment and try to find the gun and power setting that will produce the highest BC with their particular pellet, and skew the results in their favor.
• The BC depends on the tester’s carefulness: There are a lot of things that can go wrong with the ballistic chronograph and its setup, cf.:
http://precisionrifleblog.com/2012/07/20/chronograph-accuracy-tips-15-practical-tips-to-increase-accuracy-reliability/
• A collection of things that can go wrong with determining BC can be found in the following article:
http://www.arcanamavens.com/LBSFiles/Shooting/Downloads/Programs/
Note also that a given pellet will produce different amounts of muzzle energy (ME) in different guns. Often, heavy pellets will produce more ME in PCP guns than in spring-powered guns, with all things being equal, cf.:
https://www.youtube.com/watch?v=dHtsJe7cD2Y
––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––
I have collected the data of this document in extensive internet searches in 2017 for my use with ballistic calculators. THANKS to all who have been so helpful by publishing BCs online.
After amassing the data I figured – Hey, this might be useful to others. I have been helped greatly through forum posts and YouTube videos, I gladly return the favor!
So, here it is, and without any responsibility or liability on my part for its correctness, completeness, usefulness, sanity, or vanilla flavor.
If your use of the data results in you shooting out a window, you pay for it, not me. If your use of the data results in you missing the rabbit and your dinner hops off into the sunset, I won’t pay your restaurant bill, not on that evening nor on any other. Sorry, got my own bills to pay....
But if you find errors, or have more BC data to add, send me an email or PM.
If and when I find the time, I’ll gladly add it and update the list in the post.
Happy shooting!!
Matthias
COMPREHENSIVE BC Table .22cal
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Below are the introductory comments to a
comprehensive internet wide collection of ballistic coefficient data.
The table (1 page) and supporting evidence (50 pages) is found in a PDF document in my dropbox.
(I tried to condense the file size, but because of the photos of rebranded pellets the PDF is too large to attach in a forum post).
Link to the PDF file:
https://www.dropbox.com/s/dkf9174yr69igw4/BC%20Pellet%20Table.%20%20.22cal.%20%202018-10-02.%20%20V.125.pdf?dl=0
The heart of this 50-page article is the table on the second page – the pellet table – an overview of pellets with a relatively high ballistic coefficient (BC) (as published), with the following characteristics:
• .22 cal (5.5mm)
• High quality pellets (brands: JSB, H&N, RWS, Air Arms, Crosman)
• Usually available in the US
Often, main pellet manufacturers rebrand pellets, selling them under a different brand and sometimes with a different pellet name. There is some discussion whether these are the same pellets or different, and I tend to think that most of them are so similar that the BC will also be very similar. (Links are included in the section Rebranded Pellets below the table.)
The bottom part of the table includes a rebranding list, as rebranded pellets are not mentioned separately as to make the table more complicated yet. Note that sometimes the BC was measured using a rebranded pellet, this is noted in the table with the appropriate rebranding code, e.g., RB-F.
The BC values found in the literature vary, sometimes in frustrating extremes. Some are reports of actual tests, often with test conditions and calculation methods reported, others are simply lists of BC data without any information where these data were taken from.
Each BC values has a raised number after it12, sometimes a number and a letterA7. These refer to the source list of the BC data at the beginning of the table. More details about the BC data and internet links to them are included in the section Sources of BC Data at the end of this document (which also includes brands and calibers not found in the pellet table).
Each entry in the source list can consist of the following:
Author (Year-Month). Test -or- List. Ballistic Calculator used, Drag model used. Muzzle Energy (aprox.). Distance of second chronograph.
Examples:
0P H&N (2013-12). Test. 31FPE. 50y
2 ChairGun V 4.3.1. (2017). List. GA-model. Some data from the APP
4 ChronoConnect.com (2012 and Older). List
7B ASRA (2017). Test. ChairGun Calc, GA-Model. 32FPE. 31y
Sometimes concerns about the trustworthiness of the data are mentioned.
The difference between the published BC values has to do with many factors:
• The BC depends on the drag model used to calculate the BC. The currently best model is the GA model; many used the inferior G1 model; and the worst is a fixed drag model. The source list sometimes specifies which model was used. Also, some ballistic calculators are much more simplistic than the sophisticated, thus accurate ChairGun, cf.:
https://sites.google.com/site/scixddevexteriorballistics/
• The BC depends on the atmospheric conditions. Some calculators do not even allow entering atmospheric conditions, and some shooters might not have considered recording and entering this data.
• The BC depends on the velocity of the pellet (and the BC does not vary in any predictable way unless it reaches the speed of sound). The source list often specifies the muzzle energy used for the testing to give some indication how applicable the data is.
https://arxiv.org/pdf/1503.05504
Post #1 with G1 model, + Post #23 improved with GA model:
https://www.gatewaytoairguns.org/GTA/index.php?topic=14735.20
Bob Sterne (screen name rsterne, on the GTA forum and others), and to some extend Harry (aka Yrrah), have ventured into measuring BC data at different velocities (cf. his variable BC values for the JSB pellets in the above link). This is a very promising approach and goes beyond what this present list of published BC values accomplishes:
With a velocity-adjusted BC table, the shooter could select a BC appropriate for the muzzle velocity and intended distance to the target and use this more accurate BC for the ballistic calculations instead of a generic BC from a data base.
The ballistic calculator Strelok Pro (mobile app) is extremely powerful and allows the shooter to create new entries into its projectile data base. The shooter can enter various BC values for different velocities, or can enter the data for a completely new drag curve, specific for the pellet.
• The BC depends on the tester’s motivation:If the tester a manufacturer who wants to promote their pellets – then they might be motivated to experiment and try to find the gun and power setting that will produce the highest BC with their particular pellet, and skew the results in their favor.
• The BC depends on the tester’s carefulness: There are a lot of things that can go wrong with the ballistic chronograph and its setup, cf.:
http://precisionrifleblog.com/2012/07/20/chronograph-accuracy-tips-15-practical-tips-to-increase-accuracy-reliability/
• A collection of things that can go wrong with determining BC can be found in the following article:
http://www.arcanamavens.com/LBSFiles/Shooting/Downloads/Programs/
Note also that a given pellet will produce different amounts of muzzle energy (ME) in different guns. Often, heavy pellets will produce more ME in PCP guns than in spring-powered guns, with all things being equal, cf.:
https://www.youtube.com/watch?v=dHtsJe7cD2Y
––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––––
I have collected the data of this document in extensive internet searches in 2017 for my use with ballistic calculators. THANKS to all who have been so helpful by publishing BCs online.
After amassing the data I figured – Hey, this might be useful to others. I have been helped greatly through forum posts and YouTube videos, I gladly return the favor!
So, here it is, and without any responsibility or liability on my part for its correctness, completeness, usefulness, sanity, or vanilla flavor.
If your use of the data results in you shooting out a window, you pay for it, not me. If your use of the data results in you missing the rabbit and your dinner hops off into the sunset, I won’t pay your restaurant bill, not on that evening nor on any other. Sorry, got my own bills to pay....
But if you find errors, or have more BC data to add, send me an email or PM.
If and when I find the time, I’ll gladly add it and update the list in the post.
Happy shooting!!
Matthias
