Looking for credible articles/papers/research references for the below

[Justice1327]

1. How does a sharper shoulder angle on a rifle case help with combustion?

2. How might the surface of the chamber affect ballistic performance?

Currently reading Ammunition Demystified for the second time.

Thank you

 

[Mikecr]

I won't do a bunch of research for you, but higher shoulder angles increase powder burn in the chamber -instead of further down a bore. It holds the powder back.
A grippy chamber helps with consistent brass stretch, which affects volume of containment and bolt thrust. It holds brass forward.

 

[OG10]

Here let me google that for you…

 

[Justice1327]

I won't do a bunch of research for you, but higher shoulder angles increase powder burn in the chamber -instead of further down a bore. It holds the powder back.
A grippy chamber helps with consistent brass stretch, which affects volume of containment and bolt thrust. It holds brass forward.

I believe I know these things too, but looking for more "high level" ballistic papers/ lab results/ that have references to their criteria. for example, expand upon how a chamber impacts internal and possible external ballistics.

 

[Zen Archery]

1. How does a sharper shoulder angle on a rifle case help with combustion?


2. How might the surface of the chamber affect ballistic performance?

Currently reading Ammunition Demystified for the second time.

Thank you

Bryan Litz, John Harrison, and RG Hagel will keep you busy for a while.

 

[wilehunting]

P. O. Ackley could be a good reference. He liked a 40 degree shoulder, his improved cartridges have more capacity over standard base cartridge, more power burned in case, more efficient, less extreme velocity spread, less throat erosion, less bolt thrust, less case stretch.

 

[Koda_]

1. How does a sharper shoulder angle on a rifle case help with combustion?

2. How might the surface of the chamber affect ballistic performance?

Currently reading Ammunition Demystified for the second time.

Thank you

1. helps improve keeping the cartridge centered in the bore over shallower shoulders.
2. smoother throat less pressure. (Im not certain about the chamber surface itself but this is as close as I know of...)

1: https://www.outdoorlife.com/guns/modern-cartridge-design/
2: