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I’ve been reviewing a lot of the historical data on the various 50 caliber bullets used in World War 2. The DCS values for muzzle velocity and weight are different from data in the historical and contemporary sources in some instances. In the first part of this post I will present data showing the muzzle velocities, weight and dispersion for these bullets. All the data presented will be for the 36 inch Barrel Aircraft Machine Gun version of the Browning 50 caliber. In the second part, we’ll get a little more in depth with data. We will also construct firing tables and compute the trajectories of the bullets using historical methods and data. With that out of the way. Let's begin by comparing the DCS data in the CoreMods\WWII Units\Weapons\Weapons.lua file to some contemporary and historical data. The table Below shows the values In game Vs the historical data. I’ve also added some data for the M1 incendiary bullet, which was one of the most commonly used in American aircraft. DCS M2 AP DCS M8 API DCS M20 APIT M2 AP Historical Data M8 API Historical Data M20 API Historical Data M1 Incendiary V0 (Muzzle Velocity MPS) V0 (Muzzle Velocity MPS) V0 (Muzzle Velocity MPS) V0 (Muzzle Velocity MPS) V0 (Muzzle Velocity MPS) V0 (Muzzle Velocity MPS) V0 (Muzzle Velocity MPS) 830 860 875 864 899 899 912 Bullet Weight Kg Bullet Weight Kg Bullet Weight Kg Bullet Weight Kg Bullet Weight Kg Bullet Weight Kg Bullet Weight Kg 0.0458 .0403 0.0410 0.046 .042 .0396 0.040049 Da0 (Dispersion) Da0 (Dispersion) Da0 (Dispersion) Da0 (Dispersion) Da0 (Dispersion) Da0 (Dispersion) Da0 (Dispersion) 0.00085 0.00085 0.00085 0.001 0.001 0.001 0.001 100% Dispersion: Mils 100% Dispersion: Mils 100% Dispersion: Mils 100% Dispersion Mils 100% Dispersion: Mils 100% Dispersion: Mils 100% Dispersion: Mils 6.8 6.8 6.8 8 8 8 8 Below is a table of muzzle velocities for the .50 Caliber M2 AP, M8 API and M1 Incendiary in the various historical and contemporary documents.The table also includes a link to the source material. Bullet: Muzzle Velocity: FPS Muzzle Velocity MPS: Source: Link To Source M2 AP 2835 864.07 Terminal Ballistic Data 1945 https://cgsc.contentdm.oclc.org/digital/collection/p4013coll8/id/2373/rec/8 M2 AP 2845 867.11 Terminal Ballistic Data 1944 /43 https://cgsc.contentdm.oclc.org/digital/collection/p4013coll8/id/2327/rec/1 M2 AP 2845 867.11 Test Method Standard V50 Ballistic Test For Armor MIL STD-662F 1997 https://www.abbottaerospace.com/downloads/mil-std-662f-v50-ballistic-test-for-armor/ M2 AP 2845 867.11 NDRC Study Effects Of Weapon Impacts https://www.loc.gov/resource/gdcmassbookdig.effectsofimpacte01unit/?sp=421 M2 AP 2840 865.59 TM 9-225 Browning Machine Gun .50 Caliber AN-M2 Aircraft https://www.google.com/books/edition/Browning_Machine_Gun_Caliber_50_AN_M2_Ai/nXySRue3QAYC?hl=en&gbpv=1 M2 AP 2845 867.11 TM-9-2200 Small Arms https://archive.org/details/TM9-2200/page/n203/mode/2up M2 AP 2840 865.59 TM 9-219 AN M3 Basic Aircraft Machine Gun https://archive.smallarmsreview.com/archive/detail.arc.entry.cfm?arcid=7268 M8 API & M20 APIT 2946 897.89 AFM 51-44 Fighter and Fighter Bombers Employment in Tactical Air Operations https://archive.org/details/fighter-fighter-bomber-employment-in-tactical-air-operations-usaf/page/55/mode/1up M8 API & M20 APIT 2950 899.12 TM 9-225 Browning Machine Gun .50 Caliber AN-M2 Aircraft https://www.google.com/books/edition/Browning_Machine_Gun_Caliber_50_AN_M2_Ai/nXySRue3QAYC?hl=en&gbpv=1 M8 API & M20 APIT 2950 899.12 TM 9-219 AN M3 Basic Aircraft Machine Gun https://archive.smallarmsreview.com/archive/detail.arc.entry.cfm?arcid=7268 M8 API (45 Inch Barrel) 3045 982.07 FT 0.50AA-T1 1946 Firing Table M8API Heavy Barrel https://archive.smallarmsreview.com/archive/detail.arc.entry.cfm?arcid=3561 M1 Incendiary 3100 944.83 TM-9-2200 Small Arms https://archive.org/details/TM9-2200/page/n203/mode/2up M1 Incendiary 2990 911.31 TM 9-225 Browning Machine Gun .50 Caliber AN-M2 Aircraft https://www.google.com/books/edition/Browning_Machine_Gun_Caliber_50_AN_M2_Ai/nXySRue3QAYC?hl=en&gbpv=1 M1 Incendiary 2990 911.31 TM 9-219 AN M3 Basic Aircraft Machine Gun https://archive.smallarmsreview.com/archive/detail.arc.entry.cfm?arcid=7268 Below are images from the sources On Muzzle Velocity. Images Projectile Weight: For the weight data we’ll use one source, the blueprints for the projectiles. The blueprints for the projectiles have two different weights. The Standard weight and the Alternate weight. We’ll be using the Alternate weight of the projectiles, where applicable, the M2 AP, M8 API and M20 APIT. The reason for this is explained below the table. M2 AP 50 M8 API M20 API M1 Incendiary Weight 708 649 620 633 Alternate Core 708 649 612 643.5 std Core 718 662 624 633 Alt Core Kg 0.04588 0.0420 0.0396 DCS KG 0.0458 0.0403 0.041 DCS Grains 706.694 621.829 632.63 M2 AP https://archive.smallarmsreview.com/archive/detail.arc.entry.cfm?arcid=13268 M8 API https://archive.smallarmsreview.com/archive/detail.arc.entry.cfm?arcid=13265 M20 APIT M1 Incendiary According to a Ballistic Research Laboratory Report and Ordnance Research and Development .In 1943, due to supply shortages. The material for all the armor piercing cores was changed in the 50 caliber bullet. This reduced the weight of all the 50 caliber projectiles which made use of an armor piercing core, the M2 AP M8 API, and M20 APIT. The majority of these bullets were assembled with the alternate core. Which is why the weights presented are based on the alternate weight of the projectile. Army Ordnance Research and Development Report Dispersion: Preface, Units of Measure. In the discussion below the data is given in the value of mils. In this case we are referring to milliradians. Where one mil is = 0.057296 degrees. At a range of 100 feet, 1 mil = 1.2 inches. A table from the Air Force Manual Fighter Gun Harmonization provides further detail in the spoiler. According to this comment by Yo-Yo https://forum.dcs.world/topic/207864-closed-m61-dispersion/page/2/#comment-3916757 The 100% dispersion, in mils, of the weapons in DCS can be computed by multiplying the value Da0 by 8000. As 0.0022 * 8 = 0.0176 radians * 1000 = 17.6 mils. Thus we can determine the game value of dispersion , Da0, of a weapon system by dividing the 100% dispersion in mils of the weapon system by 8000. In multiple documents over a period of several years. The Air Force quoted the 100% dispersion circle as 8 mills for the 50 caliber machine gun across multiple aircraft. Another value commonly used throughout the documents is the value for 75% dispersion, which is 4 mils. The dispersion rating of 8 mils 100% is the same as 4 mils 75%. Both ratings have the same standard deviation and are products of the same normal distribution. The dispersion notation of a percentage and value in mils is based around normal distribution. The equation used to compute the value is given in the National Defense Research Committee (NDRC) report Analytic Studies in Aerial War. https://www.loc.gov/resource/gdcmassbookdig.analyticalstudie02bush/?sp=38 Equation 11 states: The diameter of the dispersion in mils is = the standard deviation of the distribution * the square root of 8* ln (100/(100- The percent value of the circle) The equation uses whole numbers as the input to compute the diameter of the dispersion. For, example the 75% circle, where sigma is the standard deviation of the dispersion and is = 1.2 mils. The equation is (1.2*(sqrt(8*ln(100/(100-75))) = Diameter 3.996 mils By setting sigma to 1.2 and using the equation to compute we get a result that approximately matches the data in the historical sources. Diameter mils Sigma mils % circle 3.996262134 1.2 75 8.071276938 1.2 99.65 Having established a standard deviation for the distribution. We can now compare our results to some of the historical data. Below I will present the historical sources and links. As a side note it looks like there may have been a typing error when the dispersion was computed. If we work backwards from the DCS dispersion value and compute the standard deviation of the dispersion, in game. It looks like someone may hit 1.02 instead of 1.2 when they computed the value of Da0. Da0*8000 = 100% mils The DCS value for the 100% dispersion in mils = .00085. Thus Da0 *8000 = 6.8 mils 100%. If we use the NDRC dispersion equation to find the 99.65% radius the standard deviation is 1.02. As (1.02*(sqrt(8*ln(100/(100-99.65))= 6.86 Da0 All DCS 50 Cals Dao * 8000 =mils 100% DCS 50 Cal Std Dev(Sigma) DCS 100%Radius NDRC Method 0.00085 6.8 1.02 6.8605 On to the sources and pics The Standard Deviation (sigma) of 1.2 mils agrees with data on the M8 API as fired from aircraft. This was figure was published in the NDRC report Analytic Studies in Aerial War on page 105 https://www.loc.gov/resource/gdcmassbookdig.analyticalstudie02bush/?sp=123&st=image&r=-0.299,0.05,1.611,1.294,0 The Small Arms Development Report also contains a table, which gives the mean radius of dispersion of various 50 caliber ammunition in inches at 600 yards. At 600 yards 1 mil is = to 7.2 inches. Thus, the mean radius of dispersion can be computed for each of the bullets. As the mean radius of dispersion Inches / 7.2 = Mean Radius of Dispersion mils. https://archive.smallarmsreview.com/archive/detail.arc.entry.cfm?arcid=13265 Bullet Name Mean Radius of Dispersion at 600 yards in Inches Mean Radius of Dispersion Mils M8 API 12 1.666666667 M2 AP 50 Cal 10 1.388888889 M1 Incendiary 50 cal 12 1.666666667 M20 APIT Std Core 12 1.666666667 M23 Incendiary 50 12 1.666666667 M21 Headlight Tracer 20 2.777777778 Ball M2 50 Cal 9 1.25 M10 Tracer 50 Cal 20 2.777777778 The first edition of the “Fighter Gunner Manual” the dispersion is given. As has the dispersion listed as 100% 8 mil and 4 mil 75% This same graphic appears in the later manual. Air Force Manual 64 Fighter Gunnery https://archive.org/details/air-forces-manual-no.-64-fighter-gunnery-firing-rockets-dive-bombing-1-may-1945/page/66/mode/1up Boresight and alignment charts at the back of this manual confirm that almost every aircraft used by the Air Force during the war had a dispersion rating of 4 mil 75% eg 1.2 sigma. Meaning the 100% value was 8 mils. The P-51b shows the 75% dispersion is 4 mils as do all most all the fighter aircraft used by The Army Air Force at this time. 4 mil 75% / 8 mil 100% was still the standard in the 1950’s https://www.google.com/books/edition/AF_Manual/81krAQAAMAAJ?hl=en&gbpv=1&pg=PA155&printsec=frontcover All of this information seems to indicate the 100% dispersion circle for the 50 caliber is around 8 mils and therefore the value Da0 should be set closer to 0.001. If you made it this far, thanks for taking the time to read all this. In the next few posts I’ll be adding some more information and building some ballistic tables for various aircraft weapons.

Is there a mod for a missile with a conventional warhead ⁓5t or bigger like the South Korean ballistic missile Hyunmoo-V? I know there is because Ive seen videos of it but I was unsuccessful finding one. like this one: Also is there is a SSM nuclear missile that wont destroy the whole planet like 4Mt max? Or any other crazy mods like this hypersonic cruise missile: