Bullets With Grooves

[asd9055]

These days I nejoy shooting cast lead in my handguns. Lot's of fun. Do those grooves in the cast lead count?

 

[FEENIX]

I find this old article (2018) about bullets with grooves https://www.americanrifleman.org/content/getting-to-the-bottom-of-grooved-bullets/#:~:text=Barnes%20named%20the%20bullet%20the%20Triple-Shock%20X%20Bullet,around%20the%20harder%20Partition%20midsection%20to%20decrease%20pressure interesting. In particular, the original Nosler partition had a groove 60 years earlier and ...

No matter the shape, depth or number of grooves bullet manufacturers place around their bullets with a solid shank, they have solved the drawbacks of fouling and excessive pressure, resulting in great all-around game bullets.

 

[RockyMtnMT]

These days I nejoy shooting cast lead in my handguns. Lot's of fun. Do those grooves in the cast lead count?

Yes

 

[Hand Skills]

I find this old article (2018) about bullets with grooves https://www.americanrifleman.org/content/getting-to-the-bottom-of-grooved-bullets/#:~:text=Barnes%20named%20the%20bullet%20the%20Triple-Shock%20X%20Bullet,around%20the%20harder%20Partition%20midsection%20to%20decrease%20pressure interesting. In particular, the original Nosler partition had a groove 60 years earlier.

Good article, @FEENIX

Thanks for the link.

I believe this quote speaks to the primary mechanism at play


"Lubrication grooves on cast lead-alloy bullets not only hold lubricant, but provide a port for material displaced by rifling."

 

[asd9055]

I just realized, cast lead have grooves and they are monos by definition. I know the big ones are a killer on bears and were on Bison

 

[asd9055]

Good article, @FEENIX

Thanks for the link.

I believe this quote speaks to the primary mechanism at play


"Lubrication grooves on cast lead-alloy bullets not only hold lubricant, but provide a port for material displaced by rifling."

I second this. And as Paul Harvey used to say signing off "....and now you know the rest of the story"

 

[RockyMtnMT]

https://agodemar.github.io/FlightMechanics4Pilots/FlightMechanics4Pilots/mypages/drag-polar/#:~:text=Aircraft%20parabolic%20drag%20polar

This is well over my head, but appears to be a drag that is induced in airplanes by the lift that is created by the wing. I could be wrong here.

I am very serious when I ask for clarification about drive band induced parabolic drag.

 

[JakeC]

I came to this thread to add more info from those links. I even attempted to add to your comment and even give you a nod.

I don't believe for a second you don't know what parabolic drag is or that you don't know what I mean. You submitted a patent and and made it a design feature for your bullets, but I'm to believe you don't know what I mean?

I'm sorry, but I'm not going to answer that.

He's literally just asking you a question in a thoughtful conversation and you pivot straight to "is this a test?" it sounded like a legit question to me. Hardness and bearing surface would effect pressure on rifling more than density, but what you were saying indirectly is that without mitigating techniques like grooves a lower density material of the same weight will have more surface area. That took me a second. And as far as parabolic drag, I thought "all drag is a parabolic function so we just say drag". Parabola refers to the shape of a drag graph, the flight of a projectile, and the shape of hammer drive bands. I wondered if you were referring to a different problem or a subset of drag types or a new BC function. Is parabolig drag just a qualifying descriptor, like saying exponential growth? Or does it refer to something specific?

 

[asd9055]

He's literally just asking you a question in a thoughtful conversation and you pivot straight to "is this a test?" it sounded like a legit question to me. Hardness and bearing surface would effect pressure on rifling more than density, but what you were saying indirectly is that without mitigating techniques like grooves a lower density material of the same weight will have more surface area. That took me a second. And as far as parabolic drag, I thought "all drag is a parabolic function so we just say drag". Parabola refers to the shape of a drag graph, the flight of a projectile, and the shape of hammer drive bands. I wondered if you were referring to a different problem or a subset of drag types or a new BC function. Is parabolig drag just a qualifying descriptor, like saying exponential growth? Or does it refer to something specific?

And the race is on....

 

[JakeC]

Yeah grooved bullets have been around since at least the crimean war. I don't know if this is true but I always assumed that the grooves in Minie balls were to actually increase drag like arrows on a feather, to compliment the rifling. Just an assumption I made as a kid. Maybe they were to lower bore friction though, anyone know?

 

[JakeC]

And the race is on....

Keep your drawers on, literally just trying to learn something.

 

[RockyMtnMT]

Yeah grooved bullets have been around since at least the crimean war. I don't know if this is true but I always assumed that the grooves in Minie balls were to actually increase drag like arrows on a feather, to compliment the rifling. Just an assumption I made as a kid. Maybe they were to lower bore friction though, anyone know?

I would assume it was an effort to increase range by increasing velocity.

 

[asd9055]

Just enjoying som guiness, I learn something everyday here

 

[asd9055]

BTW I like to know what PDR is, how is estimated/calculated, and what effect it has on bullets