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Bore Diameter relative to Recoil in SAME WEIGHT bullets

98s1lightning

Well-Known Member
Joined
Feb 24, 2024
Messages
275
Location
RI
If you take Surface Area of bullet
Multiply
π • radius squared (can't write it on my keyboard)

Then apply Force
Use a constant of whatever it may be to launch said bullet to 2800fps is it something like 50,000psi (I could be way off here I'm attempting to communicate)

Will bullets of SAME WEIGHT recoil more in larger diameter caliber if rifles weighed the same and applied force was the same? (or maybe this is where I don't understand it may take different amounts of force since surface area is different?)

I don't know how to word it exactly, but I think a 100gr 22cal, and 100gr 30 cal at same speeds will recoil differently if rifles weigh the same.

At the risk of sounding like a dummy, I've wondered about this. There's some incredibly smart people on here that will set me straight!
 
Recoil energy is a function of the weight of the rifle on the one hand (full weight includes everything attached to it) versus the weight of what you're forcing down the barrel (weight of bullet plus weight of powder) and how fast you're pushing it (velocity).

The caliber of the bore doesn't come into it directly. Though as mentioned above, like weight bullets will be longer in a smaller caliber, requiring more pressure to get it to the same velocity.

Not sure if this gets to what you were asking.
 
Seems like once engraving starts the force isn't as much? I'll state this, having 2 guns with 2 different bores 458 and 30cal creating the same muzzle energy, the 458 (45-70) has less recoil felt or not than my 300wm.
 
I would think it may pertain more to the amount of powder in said cartridges maybe? Say for instance a120-125 grain bullet out of a 25-06 your max powder charge is gonna be around 50 grains depending on the powder. Same grain bullet in say a 300 RUM is gonna be closer to 110 grains max load. The more powder the bigger the boom?🤷🏼‍♂️
 
Recoil energy is a function of the weight of the rifle on the one hand (full weight includes everything attached to it) versus the weight of what you're forcing down the barrel (weight of bullet plus weight of powder) and how fast you're pushing it (velocity).

The caliber of the bore doesn't come into it directly. Though as mentioned above, like weight bullets will be longer in a smaller caliber, requiring more pressure to get it to the same velocity.

Not sure if this gets to what you were asking.
No where in the equation for calculating recoil will you find "bore diameter"
This! @98s1lightning, you are complicating things unnecessarily if you have all the attributes; there are plenty of (felt) recoil calculators out there, such as:

https://shooterscalculator.com/recoil-calculator.php
 
He's onto something though, because one thing a bigger bore provides is larger EXPANSION RATIO

Meaning a faster powder can be used..

Same quantity of a faster powder will give more pressure

More pressure = more velocity


More velocity = more recoil
 
He's onto something though, because one thing a bigger bore provides is larger EXPANSION RATIO

Meaning a faster powder can be used..

Same quantity of a faster powder will give more pressure

More pressure = more velocity


More velocity = more recoil
Except that he specified equal bullet weight and equal velocity. If everything else is equal, there would be no difference in actual recoil of the two calibers, but that is actually impossible. If different powders or different charge weights of the same powder are used to get equal velocity, then the difference in mass of the powder charges will result in different recoil. As mentioned already, a smaller bullet is going to create more friction, so it will be impossible to use the same weight of the same powder and get equal velocity.
 
My thought on the bore diameter/surface area of the back of the bullet

If you apply 50,000psi to a 22cal surface area versus a 30cal area

The 30 gets more energy because its 50,000 times the larger surface area is a bigger number.

Just another way to say it

Yes I'm confused!
😆

Thanks for replies its interesting to hear what you guys think
 
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