View Single Post
Old December 18, 2018, 01:39 PM   #26
44 AMP
Join Date: March 11, 2006
Location: Upper US
Posts: 25,558
You would be better off looking at choked flows and supersonic flow theory. There you would gain the understanding those who say that the form factor (bottlenecked case) does not result in a pressure increase can not grasp.

I think I grasp it pretty well, I just think it doesn't apply to cartridge cases the same way it does to a hose. Yes, I understand about fluid dynamics, gas laws, venturis, and other things. The hose nozzle analogy is accurate, for a hose, but not so much for cartridge cases, because there is no changing the "nozzle size". Also, unlike a water hose, where you are using one standard system pressure and varying the nozzle size, cartridges have different pressures, created by the type and amount of powder we put in them. Each one is different.

Why does a .357 Magnum run at 35K and a .223 at 55k (or 62k?) not because one is a straight case and the other is bottlenecked, but because of OTHER FACTORS that dictate what the safe and allowable pressures can be.

The guns they are being used in is the major factor.
All else being equal (and it almost never is) bigger bullets tend to work better.
44 AMP is offline  
Page generated in 0.01853 seconds with 8 queries