Wish I had some popcorn. You guys left me so far in the dust I need something to do
Yep. Same as hydraulic brake systemssee the calcs--- lets take a set pressure to simplify--62,000 psi chamber pressure--- that same pressure is exerted on a .470 bolt face vs a .585 bolt face --- same pressure exerted over a larger area equals more force, dont care how big the lugs are if they are equal in both guns the lugs in the larger bolt face will see higher forces
think of it this way--- 62000 psi is pounds per square inch so the amount of force is dependent upon the area it exerts the force over-- a .470" bolt face is .1735 square inches -- a .585 bolt face is .2712 square inches, soooo at 62000 pounds per square inch you would take 62000 x .1735 = 10757 pounds of force for the .470" bolt face---BUT 62000x .2712 would be 16814 pounds of force for the larger .585" bolt face---make sense now?
Finally! After 4 + pages, the word "hydraulics" appears. Very simple concept, if you have a finite pressure but need to apply more force to do more work, increase the diameter (surface area) of the cylinder. In this case the bolt is the cylinder, the lugs resist the "work" the hydraulic pressure is trying to do, namely shear or move the lugs.Yep. Same as hydraulic brake systems
I was thinking the same thing about both of you arguing the same point . I had to keep scrolling back up to the posters name to see which one of yall were trying to prove the same point . I was getting dizzy !!I just checked all Cohunts math and I checked mine again and figured out we said the same thing. There is more actual force exerted on the large bolt head than the smaller one.
Its because you are not placing a 60,000 lb
weight on the bolt, you are applying 60,000lbs to every square inch on the bolt...so back to your table example you're not placing a 1000lb weight on top of the 4ft square table, instead you're placing one 1000lb weight on every square inch of the table, which would effectively transfer 2,304,000lbs to the floor, vs a 1ft table which would only be 144,000lbs transferred to the floor.
4ft x 4ftx 144sq in per sq ft= 2,304,000
1ft x 1ft x 144sq in per sq ft= 144,000
Yes, but you won't with a .223 bolt face. What is different.........I feel that the issue you and others have seen first hand are more due to being overpressure than the bolt face diameter...if you run a RUM up to 80k+ psi you would end up with bolt lug set back also.
Yes, but you won't with a .223 bolt face. What is different.........
WELLLLLL (it actually is based off the insdie of the case, not the outside)--- it is actually a very complicated equation/calculation due to manufacturing differences and specsSo if you rebate the case head on a Lapua you could safely run it up to 80k and not worry about bolt lug set back?
Possibly, I don't know of anyone that has done it. However I do know that lug setback has happened on lapua bolt faces. Do you know of any cases of lug setback on a .223?So if you rebate the case head on a Lapua you could safely run it up to 80k and not worry about bolt lug set back?
So if you rebate the case head on a Lapua you could safely run it up to 80k and not worry about bolt lug set back?
This makes more sense. So I guess a rebated case would have the same or similar bolt thrust as a non rebated case I guess, simply due to the case size itself.WELLLLLL (it actually is based off the insdie of the case, not the outside)--- it is actually a very complicated equation/calculation due to manufacturing differences and specs
what we provided was the "easy" calc methods of bolt thrust--but if you read the wikipedia page I listed earlier the measurement is actually the inside diameter of the brass case, since each brass manu is different it is very hard to actually calc the true bolt thrust using these calculation methods, also the different brass alloys and state of softness/hardness will change the "case grip" to the side walls of the chamber thus actually changing the bolt thrust numbers (this is shown with NATO proof testing where they oil the proof rounds for testing to increase the bolt thrust numbers -- see the equation below for Ainternal, is actually the INSIDE area of the cartridge case head which will vary based on the "web" design
Formula
where:
View attachment 172620
- Fbolt = the amount of bolt thrust
- Pmax = the maximum (peak) chamber pressure of the firearms cartridge
- Ainternal = the inside area (of the cartridge case head) that the propellant deflagration gas pressure acts against
hows that for a mouthful
Possibly, I don't know of anyone that has done it. However I do know that lug setback has happened on lapua bolt faces. Do you know of any cases of lug setback on a .223?