Artillery rear sight question

Bill Jensen · 10-02-2008, 08:52 PM

Hi there enthusiasts!

Concerning the rear sight of the artillery luger, why is the sight increasingly off axis to the left as it is raised to different heights?

Is it that the gun twists in your hand because of the rifling twist (does this really happen before the bullet has left the barrel)?

Or is it that for some reason the bullet flies a bit to the right in flight?

Sincerely,
Bill Jensen

Ron Wood · 10-02-2008, 09:07 PM

Bill,
You basically have the concept. The camming of the rear sight to the left is intended to compensate for the drift of the bullet at long ranges due to the right hand spiral imparted by the rifling. It does not happen before the bullet has left the barrel but is, as you suspect, designed to overcome the tendency for the flight of the bullet to drift during flight.

Bill Jensen · 10-02-2008, 09:18 PM

Hi Ron,

Is this drift due to a spiralling bullet mass from the Coriolis effect from the rotation of the earth? If so, does the bullet fly the other way in the southern hemisphere? And straight at the equator?

Sincerely,
Bill Jensen

lugerholsterrepair · 10-02-2008, 09:42 PM

Is this drift due to a spiralling bullet mass from the Coriolis effect from the rotation of the earth? If so, does the bullet fly the other way in the southern hemisphere? And straight at the equator?

Man! That WOULD be something the Germans would do!

the drift of the bullet at long ranges due to the right hand spiral IMPARTED BY THE RIFILING.

Jerry Burney

Ron Wood · 10-03-2008, 12:28 AM

Interesting question. The drift of the bullet has nothing to do with the Coriolis effect. The Coriolis effect deals primarily with fluid dynamics, i.e. atmospheric movement and sink drains, not the solid and aerodynamics of ballistic flight.

RalphH · 10-04-2008, 04:58 PM

Greetings, Gentlemen,

Let me add my two cents. The bullet has a right hand twist. It is constantly falling, so the air friction is greater on the bottom. The bullet has a tendency to roll to the right, using the air cushion as a platform.

I think.

MikeP · 10-05-2008, 12:02 AM

I'm glad Ron cleared up the Coriolis issue.
I was wondering if I should hold right if shooting below the equator.

raygun · 10-05-2008, 12:39 AM

Quote:

Originally posted by MikeP
I'm glad Ron cleared up the Coriolis issue.
I was wondering if I should hold right if shooting below the equator.

I think you will find that unless your an Artilleryman and actually firing a serious piece of artillery, several miles with pin point accuracy, you will not have to worry too much about the earths rotation .

Are there any Navy Gunners on board ? they can probably tell us a thing or two about this also ?

lugerholsterrepair · 10-05-2008, 11:17 AM

You guys can't be serious....

Jerry Burney

10-02-2008, 08:52 PM	#1
Bill Jensen User Join Date: Dec 2004 Location: Kirkland, WA Posts: 28 Thanks: 0 Thanked 0 Times in 0 Posts	Artillery rear sight question Hi there enthusiasts! Concerning the rear sight of the artillery luger, why is the sight increasingly off axis to the left as it is raised to different heights? Is it that the gun twists in your hand because of the rifling twist (does this really happen before the bullet has left the barrel)? Or is it that for some reason the bullet flies a bit to the right in flight? Sincerely, Bill Jensen

10-02-2008, 09:07 PM	#2
Ron Wood Moderator 2010 LugerForum Patron Join Date: Jun 2002 Location: Santa Teresa New Mexico just outside of the West Texas town of El Paso Posts: 6,988 Thanks: 1,067 Thanked 5,099 Times in 1,676 Posts	Bill, You basically have the concept. The camming of the rear sight to the left is intended to compensate for the drift of the bullet at long ranges due to the right hand spiral imparted by the rifling. It does not happen before the bullet has left the barrel but is, as you suspect, designed to overcome the tendency for the flight of the bullet to drift during flight. __________________ If it's made after 1918...it's a reproduction

10-02-2008, 09:42 PM	#4
lugerholsterrepair Moderator Lifetime Forum Patron Join Date: Jun 2002 Location: Arizona/Colorado Posts: 7,763 Thanks: 4,866 Thanked 3,105 Times in 1,429 Posts	Is this drift due to a spiralling bullet mass from the Coriolis effect from the rotation of the earth? If so, does the bullet fly the other way in the southern hemisphere? And straight at the equator? Man! That WOULD be something the Germans would do! the drift of the bullet at long ranges due to the right hand spiral IMPARTED BY THE RIFILING. Jerry Burney __________________ Jerry Burney 11491 S. Guadalupe Drive Yuma AZ 85367-6182 lugerholsterrepair@earthlink.net 928 342-7583 (CO & AZ) Year Round 719 207-3331 (cell) "For those who Fight For It, Life has a flavor the protected will never know."

10-03-2008, 12:28 AM	#5
Ron Wood Moderator 2010 LugerForum Patron Join Date: Jun 2002 Location: Santa Teresa New Mexico just outside of the West Texas town of El Paso Posts: 6,988 Thanks: 1,067 Thanked 5,099 Times in 1,676 Posts	Interesting question. The drift of the bullet has nothing to do with the Coriolis effect. The Coriolis effect deals primarily with fluid dynamics, i.e. atmospheric movement and sink drains, not the solid and aerodynamics of ballistic flight. __________________ If it's made after 1918...it's a reproduction

10-04-2008, 04:58 PM	#6
RalphH User Join Date: Nov 2006 Location: North central Ohio Posts: 41 Thanks: 0 Thanked 0 Times in 0 Posts	Greetings, Gentlemen, Let me add my two cents. The bullet has a right hand twist. It is constantly falling, so the air friction is greater on the bottom. The bullet has a tendency to roll to the right, using the air cushion as a platform. I think. __________________ Regards, Ralph Boy, I love these old guns.....

10-02-2008, 09:18 PM	#3
Bill Jensen User Join Date: Dec 2004 Location: Kirkland, WA Posts: 28 Thanks: 0 Thanked 0 Times in 0 Posts	Hi Ron, Is this drift due to a spiralling bullet mass from the Coriolis effect from the rotation of the earth? If so, does the bullet fly the other way in the southern hemisphere? And straight at the equator? Sincerely, Bill Jensen

10-05-2008, 12:02 AM	#7
MikeP User Join Date: Jun 2002 Location: ILL Posts: 686 Thanks: 36 Thanked 452 Times in 198 Posts	I'm glad Ron cleared up the Coriolis issue. I was wondering if I should hold right if shooting below the equator.

10-05-2008, 11:17 AM	#9
lugerholsterrepair Moderator Lifetime Forum Patron Join Date: Jun 2002 Location: Arizona/Colorado Posts: 7,763 Thanks: 4,866 Thanked 3,105 Times in 1,429 Posts	You guys can't be serious.... Jerry Burney __________________ Jerry Burney 11491 S. Guadalupe Drive Yuma AZ 85367-6182 lugerholsterrepair@earthlink.net 928 342-7583 (CO & AZ) Year Round 719 207-3331 (cell) "For those who Fight For It, Life has a flavor the protected will never know."