The Official 2nd Amendment Appreciation Thread

[ACvol3]

This was a long while back, but I don't remember anything other than that bear.

We still hike when we're up there, but with age, knees, and in need of surgery for that hip, we're limited to relatively modest day hikes. Still, I think I'll drag Diana up to LeConte next year to watch the llamas eat lunch.

We had some hogs about run us off the trail on the way up,and then they camped out beside us all night. Those red eyes just glowing in the dark

 

[txbo]

Makes sense, it’s all trigonometry and with known points I see it.

It appears that all branches of our military have completely abandoned MOA as a unit of angular measure for snipers.

What is the current unit of measure for navigation, map reading and such?

Thanks to all that respond. This is interesting stuff.

 

[GreyWolf1129]

Was he the one that was so hungry he was eating caulk or plastic or something?

Milo was the Cub / Yearling that they had so much trouble getting out of ABR. He didn't want to leave. He would stay up in a tree so that they couldn't trap him. It was funny as all get out. The Facebook posts they did on the "Milo Update" were legendary.

 

[GreyWolf1129]

It appears that all branches of our military have completely abandoned MOA as a unit of angular measure for snipers.

What is the current unit of measure for navigation, map reading and such?

Thanks to all that respond. This is interesting stuff.

I don't think MOA is gone, but I'm not a sniper type.

Navy uses Lat / Long for navigation. Everything we (oops, they) do in navigation is using nautical units of measure. Targeting (Tomahawks, NGFS, etc.) uses another method. And the SEALS use MGRS for land nav and some other stuff that shan't be mentioned here.

I think the Coast Guard just pulls up to the beach and asks a swimmer/surfer where they are.....

 

[txbo]

I don't think MOA is gone, but I'm not a sniper type.

Navy uses Lat / Long for navigation. Everything we (oops, they) do in navigation is using nautical units of measure. Targeting (Tomahawks, NGFS, etc.) uses another method. And the SEALS use MGRS for land nav and some other stuff that shan't be mentioned here.

I think the Coast Guard just pulls up to the beach and asks a swimmer/surfer where they are.....

The sextant I have appears to use degrees.

 

[txbo]

I don't think MOA is gone, but I'm not a sniper.....

For years they used MOA turrets w MIL reticle. Most have simplified to mil/mil. Makes much more sense. Much faster and simpler.

Going MOA/MOA would accomplish the same.

 

[GreyWolf1129]

The sextant I have appears to use degrees.

Right. You are measuring the angle between the horizon, and the star / planet you are sighting. This angular measurement is expressed in degrees, which is then reduced mathematically to a "Circle of Equal Altitude", upon which you are located. Two or more sightings (three minimum, five preferred) will result in a fix within 1nm of your actual position.

EDIT: Your sextant should have degrees on the limb (curve thingy), and then a dial that is marked in minutes and seconds. All three...degrees, minutes, and seconds, are arc.

 

[GreyWolf1129]

It's been awhile, and I'm too lazy to look it up, but I think the limb goes to 60 degrees, hence the term "sextant" (sixth of a circle). I'm also thinking that the preferred altitudes for sightings were in the 35-55 degree range. Not always possible. There are (scratching my head now) 57 navigable stars, 4 planets, and then you can use the sun and the moon (upper or lower limb) for certain observations. Your sextant should have a series of "flip filters" that will allow you to look at the sun for observations (e.g. - Azimuth of the Sun, Local Apparent Noon).

Man....you're making me think now.

 

[txbo]

Right. You are measuring the angle between the horizon, and the star / planet you are sighting. This angular measurement is expressed in degrees, which is then reduced mathematically to a "Circle of Equal Altitude", upon which you are located. Two or more sightings (three minimum, five preferred) will result in a fix within 1nm of your actual position.

EDIT: Your sextant should have degrees on the limb (curve thingy), and then a dial that is marked in minutes and seconds. All three...degrees, minutes, and seconds, are arc.

When you get down to seconds, aren’t you getting pretty darn precise at the distances you are measuring?

 

[txbo]

It's been awhile, and I'm too lazy to look it up, but I think the limb goes to 60 degrees, hence the term "sextant" (sixth of a circle). I'm also thinking that the preferred altitudes for sightings were in the 35-55 degree range. Not always possible. There are (scratching my head now) 57 navigable stars, 4 planets, and then you can use the sun and the moon (upper or lower limb) for certain observations. Your sextant should have a series of "flip filters" that will allow you to look at the sun for observations (e.g. - Azimuth of the Sun, Local Apparent Noon).

Man....you're making me think now.

Interesting that it goes to 60 degrees.... that’s just slightly larger than a radian.

 

[GreyWolf1129]

When you get down to seconds, aren’t you getting pretty darn precise at the distances you are measuring?

Okay, now you've got me strip-mining my memory...trying to go back eons to remember some things.

Yes. I don't remember the exact numbers, but yes.

Oh...old navigator's trick. It can be a real b**ch trying to hold the star in the index mirror and pull it down to the horizon, so a trick an old Vietnam-era navigator taught me was to invert the sextant; find your star; then stay on it and pull the horizon (much easier to see) UP to the star.

We had a bubble sextant (bubble attachment to the scope for a false horizon in any condition of light or dark), but it still worked upside down.

Remember, there was a narrow window for star sightings. You have civil, nautical, and astronomical twilight (Sun is 6, 12, and 18 degrees below the horizon). Again, if memory serves, we had about a 10-15 minute window to get our sightings done, which sounds easy, but is another thing entirely when doing it on the bridge of a ship or sub at sea.

Okay, you're making my head hurt. Enough for one day.

 

[WallyBalls]

Milo was the Cub / Yearling that they had so much trouble getting out of ABR. He didn't want to leave. He would stay up in a tree so that they couldn't trap him. It was funny as all get out. The Facebook posts they did on the "Milo Update" were legendary.

She knew exactly which one he was. Their personalities are so great.

Her favorite thing now is the arrows they put in the FB posts. I feel like I hear “nubbin” in my house more than my own name.

 

[txbo]

Okay, now you've got me strip-mining my memory...trying to go back eons to remember some things.

Yes. I don't remember the exact numbers, but yes.

Oh...old navigator's trick. It can be a real b**ch trying to hold the star in the index mirror and pull it down to the horizon, so a trick an old Vietnam-era navigator taught me was to invert the sextant; find your star; then stay on it and pull the horizon (much easier to see) UP to the star.

We had a bubble sextant (bubble attachment to the scope for a false horizon in any condition of light or dark), but it still worked upside down.

Remember, there was a narrow window for star sightings. You have civil, nautical, and astronomical twilight (Sun is 6, 12, and 18 degrees below the horizon). Again, if memory serves, we had about a 10-15 minute window to get our sightings done, which sounds easy, but is another thing entirely when doing it on the bridge of a ship or sub at sea.

Okay, you're making my head hurt. Enough for one day.

Lol! Thanks for the education.

 

[GreyWolf1129]

Lol! Thanks for the education.

No worries. All this "radian, degrees, azimuth, reverse azimuth" stuff reminds me of a funny tale I was part of...

I'm at one of those wine, hors-doeuvre's, rub elbows, and brag about stuff that would put a spastic leopard to sleep things I used to have to go to with my wife when she was a local government bigwig. Not my thing, but I'm the mandatory elbow-guard, so I go. I'm chatting it up with a local attorney who knows me, and he's blathering on about some celestial software program he uses on his 50-something ft sailboat him and the wife go "Carib-hopping" in. He's playing with me, asking some technical questions, but I'm holding my own until he trips me up on "loxodrome", which I know, but at the moment it escaped my grasp. So he starts in on me about how I know arc to time, time to arc, sight reduction tables, sines, cosines, Pythagorean theorem for ENAV calculations, and "you don't even know something as basic as a loxodrome?"

He was really having fun boxing me in, so here was my response:

"Mr. _____, you remember the ___shooting?"

"Yes, why?"

"Are you aware that the ME said I made a one-in-a-thousand shot?"

He looks at me...keeps looking....and then a smile creeps across his face. "Here, let me go get you a beer."

Priceless. He and I remain friends to this day.

 

[txbo]

No worries. All this "radian, degrees, azimuth, reverse azimuth" stuff reminds me of a funny tale I was part of...

I'm at one of those wine, hors-doeuvre's, rub elbows, and brag about stuff that would put a spastic leopard to sleep things I used to have to go to with my wife when she was a local government bigwig. Not my thing, but I'm the mandatory elbow-guard, so I go. I'm chatting it up with a local attorney who knows me, and he's blathering on about some celestial software program he uses on his 50-something ft sailboat him and the wife go "Carib-hopping" in. He's playing with me, asking some technical questions, but I'm holding my own until he trips me up on "loxodrome", which I know, but at the moment it escaped my grasp. So he starts in on me about how I know arc to time, time to arc, sight reduction tables, sines, cosines, Pythagorean theorem for ENAV calculations, and "you don't even know something as basic as a loxodrome?"

He was really having fun boxing me in, so here was my response:

"Mr. _____, you remember the ___shooting?"

"Yes, why?"

"Are you aware that the ME said I made a one-in-a-thousand shot?"

He looks at me...keeps looking....and then a smile creeps across his face. "Here, let me go get you a beer."

Priceless. He and I remain friends to this day.

Lol! I love those stories.

Today’s technology makes it easier for many people to do many things...... until the batteries run out.

 

[GreyWolf1129]

Back to guns. GV is ignoring my barrel question 'cause I unintentionally hijacked his thread.

 

[Grand Vol]

Heyyyyyyyy GV! I had no idea Daniel Defense was so close to me. So it got me to thinking.....

Suppose I was thinking about a 16" heavy barrel in 1/7 twist for my 6721. Does anyone make them, and if so would you perhaps have a recommendation? I'm just asking for a friend.

I'll have to reply way later...

 

[Grand Vol]

Back to guns. GV is ignoring my barrel question 'cause I unintentionally hijacked his thread.

GV has been way busy dealing with Tay-Tay in Pasadena and corporate meetings in Wisconsin.

 

[GreyWolf1129]

GV has been way busy dealing with Tay-Tay in Pasadena and corporate meetings in Wisconsin.

No worries.

 

[NorthDallas40]

It appears that all branches of our military have completely abandoned MOA as a unit of angular measure for snipers.

What is the current unit of measure for navigation, map reading and such?

Thanks to all that respond. This is interesting stuff.

Over long distances I think lat/long makes sense.

One time zone is 15 degrees of longitude.

One nautical mile is basically one minute of arc so there are 60 nautical miles in a degree of longitude. 15 x 60 = 900 nautical miles roughly in a time zone.

One second of arc is a 60th of a nautical mile, around 100 ft.

Simple rules easy to remember.

 

[NorthDallas40]

For years they used MOA turrets w MIL reticle. Most have simplified to mil/mil. Makes much more sense. Much faster and simpler.

Going MOA/MOA would accomplish the same.

My ‘06 has a Mildot reticle. It actually means milliradian. One milliradian = 3.43 minutes of arc or MOA.

Without getting two carried away to know your spread for a small angle the sine of the angle is roughly equal to the angle if the angle units are “radians”. This is part of a simple rule set we call the “small angle approximation”. So for a Mildot take your distance and multiply by 0.001 and that will tell you the linear distance between the “milliradian dots” at range. Super quick range estimator too if you know roughly the size of what’s under the reticle.

 

[txbo]

My ‘06 has a Mildot reticle. It actually means milliradian. One milliradian = 3.43 minutes of arc or MOA.

Without getting two carried away to know your spread for a small angle the sine of the angle is roughly equal to the angle if the angle units are “radians”. This is part of a simple rule set we call the “small angle approximation”. So for a Mildot take your distance and multiply by 0.001 and that will tell you the linear distance between the “milliradian dots” at range. Super quick range estimator too if you know roughly the size of what’s under the reticle.

Oh I’m very familiar with both MRAD and MOA. My point was that having turret adjustments and reticle both using the same unit avoids the need for conversion. It’s only common sense that took way too long to implement.

And yes, I do find mrad as very easy for range estimation. Considering the average male human is 6 feet tall, at 1000 yard he would be 2 mils. At 500 yards...4 mil. At 250 yards...8 mils. ETC.

 

[DEFENDTHISHOUSE]

American Rifleman | The CMP M1911s: The Inside Story

 

[txbo]

Over long distances I think lat/long makes sense.

One time zone is 15 degrees of longitude.

One nautical mile is basically one minute of arc so there are 60 nautical miles in a degree of longitude. 15 x 60 = 900 nautical miles roughly in a time zone.

One second of arc is a 60th of a nautical mile, around 100 ft.

Simple rules easy to remember.

Makes sense. Thanks.

 

[txbo]

American Rifleman | The CMP M1911s: The Inside Story

What do you think the Remington will bring at auction?