Ballistics - Add M855/M856/M855A1/M856A1 ammo and magazines

[Cplhardcore]

When merged this pull request will:

• adds common nato caliber 5.56 ammunition and magazines

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[LinkIsGrim]

Isn't B_556x45_Ball already supposed to be regular M855?

[Cplhardcore]

Isn't B_556x45_Ball already supposed to be regular M855?

Supposed to be yes, however, its so far off what it should be for actual M855, that I decided creating a new round would be better than updating the old round

[johnb432]

Supposed to be yes, however, its so far off what it should be for actual M855, that I decided creating a new round would be better than updating the old round

Imo a bad reason. If the round is wrong, it should be corrected.

Can you provide sources for your numbers? I can't find any sources suggest the G7 ballistics coefficient should be 0.305 for M855.

[Cplhardcore]

Supposed to be yes, however, its so far off what it should be for actual M855, that I decided creating a new round would be better than updating the old round

Imo a bad reason. If the round is wrong, it should be corrected.

Can you provide sources for your numbers? I can't find any sources suggest the G7 ballistics coefficient should be 0.305 for M855.

Its a vanilla round, which is why i went with the new ammo over an update
As for values, the M855A1/M856A1 values are from Ballistic Performance of Rifle Bullets by Bryan Litz, and the M855/M856 are from https://www.rws-technology.com/en/armed-forces-law-enforcement/product/556x45-nato-ball-ss109-62gr-2422469
and https://pmcammo.com/product/x-tac-5-56k/
Im waiting on a formal fact sheet from Lake City to confirm the G1 coef of M855. but from what i can tell, around .303-.309 is about what you'll get at muzzle

[johnb432]

Its a vanilla round, which is why i went with the new ammo over an update As for values, the M855A1/M856A1 values are from Ballistic Performance of Rifle Bullets by Bryan Litz, and the M855/M856 are from https://www.rws-technology.com/en/armed-forces-law-enforcement/product/556x45-nato-ball-ss109-62gr-2422469 and https://pmcammo.com/product/x-tac-5-56k/ Im waiting on a formal fact sheet from Lake City to confirm the G1 coef of M855. but from what i can tell, around .303-.309 is about what you'll get at muzzle

2nd link doesn't specify the drag model they use to determine the BC, but I'm going to assume it's G1. Why should we use the G1 drag model for a bullet that is shaped as a G7 model (see https://en.wikipedia.org/wiki/Ballistic_coefficient#Differing_mathematical_models_and_bullet_ballistic_coefficients)? G7 is more accurate for M855 and the current BC in ACE matches with the ones provided from the 1st link.