Shooting bullet backwards.....

[Tim Singleton]

A lot of slow and subsonic shooters load big heavy bullets backward

 

[tuttlefarm]

being a former rocketeer i learned about stabilizing a projectile in flight. arrows and rockets are "fin stabilized", and bullets are "spin stabilized". the difference has to do with the center of gravity(mass) and the center of pressure relationship. in a rocket/arrow the center of gravity(balance point, center of mass) has to be forward of the center of pressure (the definition of this factor is complex) (one caliber plus is safe). if this is reversed, the rocket/arrow will tumble...the rocket will fly in circles until propellant weight is reduced to the point that the center of gravity moves forward of the center of pressure, THEN the rocket will fly straight. this latter occurance can be very scary as some of these rockets were horizontal. a spin stabilized bullet must have its center of gravity BEHIND its center of pressure.i.e. the bullet's mass is in its rear. this center of weight and center of pressure separation in a rocket/arrow is usually quite large, but in a bullet the separation is very small. this might explain the bullet "going to sleep" describe by benchrest shooters as they feel bullets have a little "wobble" just as they exit the barrel, then stabilize. firing a bullet backwards puts the center of gravity in front of the center of pressure and results in unstable flight. the bullet will start to "wobble" shortly after barrel exit and subsequently lose energy and its trajectory will be poor as far as accuracy is concerned. long boat tail bullets have their center of gravity/mass far enough behind their center of pressure as to produce superior flight characteristics...large BCs and superb long range accuracy. short stubby bullets have these two factors so close that their long range accuracy suffers, albeit short range accuracy predominates. an interesting note: fin stabilized projectiles will not fly in a vacuum but spin stabilized projectiles will. rockets flying straight in space are stabilized by internal gyroscopes...spin stabilization.

In 10 words or less, what the heck did you just say.

 

[1lnbrdg]

Years ago, I was playing with light loads / cast bullets in a 30.06. Had a pretty decent load. Off the wall thinking one day, tried some of the 147gr FMJBT military pull-down bullets, they wouldn't shoot worth a flip with any load I tried but with the reduced load, they shot a little better. Further off the wall thinking and I loaded a few up reversed. Finally found a way that those bullets were accurate.

Squirrel hunted with that load for a couple of years, would shoot sub-minute at 100yds. Haven't ever purchased any more of those bullets though.

 

[Eddie Harren]

In 10 words or less, what the heck did you just say.

+1

 

[jonbearman]

after WW1 AND WW2 GUYS BOUGHT ALOT OF SURPLUS FULL METAL JACKET AND PULLED THE BULLETS AND LOADED THEM BACK IN AND IT WAS CALLED THE POOR MANS HOLLOW POINT. tHE BASE OF FMJ BULLETS WERE SLIGHTLY CUPPED EXPOSED LEAD AND THEY WORKED ON MEDIUM SIZED GAME LIKE DEER OK. Sorry caps was on.

 

[sbhooper]

Many years ago, I knew a guy that used to do that with his .243 for reduced loads for called coyotes at close range.

 

[lpreddick]

+1

Bullets stability is a complex situation and is not easy to understand . Fin stabilized projectiles are a bit easier to understand. I have spent many hours reading about spin stabilized projectiles. I would strongly suggest reading Bryan Litz book Applied Ballistics for Long Range Shooting, esp the chapter on Bullet Stability, chafter 10 in the first edition. I have read and reread this chapter and am starting to partially understand this subject. Reversed bullets will shoot and their flatter than tip base will indeed kill game and being unstable they will dump their energy quicker than if hitting tip first. Don't expect small groups at long range.

 

[snert]

Bullets stability is a complex situation and is not easy to understand . Fin stabilized projectiles are a bit easier to understand. I have spent many hours reading about spin stabilized projectiles. I would strongly suggest reading Bryan Litz book Applied Ballistics for Long Range Shooting, esp the chapter on Bullet Stability, chafter 10 in the first edition. I have read and reread this chapter and am starting to partially understand this subject. Reversed bullets will shoot and their flatter than tip base will indeed kill game and being unstable they will dump their energy quicker than if hitting tip first. Don't expect small groups at long range.

I THOUGHT he said if you take a little toy bottle rocket and pop the cap off, fill it with black powder and caps, left over powder from lady finger firecrackers, then set it on the mound in a baseball field and light it, it will launch, turn directly at your 12 year old nuts and explode just after you leapt in the air to get out of the way....

Not that I would know.

 

[joshb]

I THOUGHT he said if you take a little toy bottle rocket and pop the cap off, fill it with black powder and caps, left over powder from lady finger firecrackers, then set it on the mound in a baseball field and light it, it will launch, turn directly at your 12 year old nuts and explode just after you leapt in the air to get out of the way....

Not that I would know.

Dang!! I thought I was the only one to do that!!! Ever shot an arrow straight up?..............and then lose sight of it...........and run like hell

 

[snert]

Dang!! I thought I was the only one to do that!!! Ever shot an arrow straight up?..............and then lose sight of it...........and run like hell

Shooting at bats at night with a bow...proof there is a God. Arrows shot straight up never come down on your head. They come down next to your little sister and that makes her mess her shorts, which results in a trip to the woodshed....ask me how I know.
Not learning anything except to shoot at an angle, I learned that bats, when hit after about ten million tries, skitter downward and that results in shrieks...from a mother who was sitting on the porch reading as the bat flopped onto the porch...ask me how I know...

 

[joshb]

Oh yeah. Those were the days. Making friends with the son of the owner of the cabin our family rented near lake Sebago, Maine.....and setting off firecrackers at the quarry. Then he tells me he knows where his Daddy keeps the dynamite he uses to clear channels in the creek............ Musta been 12 or 13

 

[snert]

Oh yeah. Those were the days. Making friends with the son of the owner of the cabin our family rented near lake Sebago, Maine.....and setting off firecrackers at the quarry. Then he tells me he knows where his Daddy keeps the dynamite he uses to clear channels in the creek............ Musta been 12 or 13

I happen to know that a bread bag full of acetlyn and oxygen set off with a ten foot piece of floor molding and a burning rag will remove all the gravel off a one lane road, put most of it in the skin of a not so bright cousins backside, will break shoddy windows and bring the local constable....oh those certainly were the days...glad I lived through my teens.

 

[joshb]

I can't stop laughing. We used 30 gallon garbage bags.

 

[mikecr]

a spin stabilized bullet must have its center of gravity BEHIND its center of pressure.i.e. the bullet's mass is in its rear.

No.
The reason bullets are spin stabilized is because center of gravity is normally behind center of pressure. So normal bullets tumble with insufficient spin, given that they are in this dynamically unstable form for tip first flight. Otherwise they would fly well enough without rifling.
Flipping the bullet around to base first flight, may or may not improve stability(depends on the bullet form).
But where you get center of gravity ahead of pressure, the bullet would fly in this mode even without spin(no longer needed).
Think yard dart with or without it's fins. It's gravity ahead of pressure even if you remove the fins. In fact it's so much gravity ahead of pressure that it will dynamically reset itself this way no matter how you throw it.
I think many bullets would do this, landing base first, if shot from a smooth bore, and pointed either direction to begin.

 

[Tim Singleton]

Speaking of bow and arrows, teenagers and their cousins
Dads prize bull shot in his big ol bag with an arrow
Just about didn't live through that one!

 

[savagedasher]

Why not shoot round ball and it wouldn't know

 

[AndyA]

Cutting Edge Bullets advertises some of their bullets as being tipped, hollow point and solid. They have a plastic insert that goes into the hollow point to make it a tipped bullet. No tip and it is a hollow point. Turn it around and shoot it as a solid.

 

[M14AMU]

I did that in 1950 with some Herter's .30 caliber bullets!

 

[chkunz]

In 10 words or less, what the heck did you just say.

I also have a background in rockets in another life and I understood all that he says. If you do not understand it, no big deal, but there are reasons we do not load bullets backwards, specifically the laws of physics.

 

[snert]

Speaking of bow and arrows, teenagers and their cousins
Dads prize bull shot in his big ol bag with an arrow
Just about didn't live through that one!

I am fairly certain that you and Josh and I lived in parallel universes! OMG...I spit my soda!

And I aint never loaded a bullet backwwards...yet...but give me some time, an audience....