Odd Long Range Shooting Question

[Deleted member 12999]

I know nothing on this subject, so excuse my ignorance. I was reading a book about an assassin who was setting up a hit with a scoped rifle. In the book he didn’t take it to a range and dial it in, but used some laser system to zero the rifle.

Is this possible or total fiction? I assume it’s BS.

Edit: in the book the shot was about 2 city blocks. 200m? (I figure)

That's not long range

 

[jaymce]

Funny story.

When in college one of my teachers was friends with Robert Parker (Spenser For Hire). Anyway he came to the class and talked about writing. One of the things that struck him was how accurate he had to be when describing details. He gave an example of "so Spencer slaps a 10 round mag of 9mm into his Wather PPK" he said a line like that will get a ton of mail.
"Wather doesn't make a 10 round mag for a PPK"
PPK dosen't come in 9mm
And on and on. He found it humorous, to him, he just wanted to describe loading a semi auto. He said he tried to be more accurate after that.

 

[40 Creedmoor fan]

I know nothing on this subject, so excuse my ignorance. I was reading a book about an assassin who was setting up a hit with a scoped rifle. In the book he didn’t take it to a range and dial it in, but used some laser system to zero the rifle.

Is this possible or total fiction? I assume it’s BS.

Edit: in the book the shot was about 2 city blocks. 200m? (I figure)

Fiction is good when it has some basis in truth. In this case, this is indeed based on actual practice. Rifles can be set up initially using laser pointers. Unfortunately, the vast majority of lasers are not powerful enough to reach 50 yards, let alone 200 yards. But let's assume that one can find a good green laser capable of reaching 50yd and zero rifle for that distance. Using a Ballistic Calculator, one can easily calculate bullet drop at 200yds for your bullet. Here's an example of perhaps the most popular cartridge: 165gr 308 Winchester.

165gr 308 Winchester Ballistic Trajectory Results
At 200 yards, the bullet drops a mere 4".

If one were to shoot a modern flat shooting cartridge like 6.5 PRC using a manually loaded "spicy" cartridge, the drop at 200yards is less than 1.5 inches!

6.5 PRC, 123gr bullet, 3350fps using Alliant RL-26 powder.

So yes, it is very close to the real thing...

 

[mac1911]

If I use the laserlite bore light calculator I can be with in a 2” or so at 200 yards.
You do need to know some details and velocity and sight height and such

 

[AHM]

I don't know if I'd trust a laser bore sight to be accurate out to 200m. I've seen tests where they mount the bore sighter to a lathe and spin it and you can see the laser on the wall making a circle as it spins.

On the one hand, I know my Bushnell muzzle bore sight laser
contains a pair of field adjustment set-screws to eliminate that error.
Although if the device actually was off-center,
I could just spin it in the muzzle four times,
and zero in on the middle of the four dots.


On the other hand, ...

I agree. I have a few, and they're hit/miss with precision and when they are off, they also aren't always off in the same direction, as it depends on how you insert it in the chamber which way is going to be off.

... last December I asked what made people believe
that a chamber bore sight laser plunked into an arbitrary chamber
would have the slightest prayer of being collinear with the barrel.

It's not as if the axis of the chamber affects the path of the boolit -
that happens at the muzzle crown.

@mac1911 confirmed that it was a failure mode for one he bought.

 

[In God We Trust]

That's not long range

I know. I can hit that all day with iron sights. I was more referring to the long range set up he was using. Bolt action, optic etc.

 

[jkelly1229]

Lasers shoot a straight trajectory. Bullets do not.

Right but gravity and wind drift don't change either.

I don't know too much about long range either

But i do know the wind drift and drop on a 180 grain sierra match king 7.62 round is consistent so as long as your sight is aligned you can then dial in your adjustments accordingly

 

[40 Creedmoor fan]

I have stopped using lasers to zero scopes. sighting through bore is far easier and faster to set 50yd zero. make a few sighting shots to get rifle to hit

At 200 meters, just about any centerfire rifle will be pretty damn close to point of impact = point of aim +/- a couple inches.

anyone using even open sights should be able to hit center of mass on a human sized target at that distance.

Ballistic trajectories are not just for 200 yards. A 308 still has decent energy at 1000 yards, and modern non-magnum cartridges can do serious damage at a mile.
200yards was used as an example, not an absolute distance. Heck, even I can shoot 1" groups at 300 yards with my 22-250 all day long and I SUCK at long distances. suuuuuuuuck.

 

[whacko]

Right but gravity and wind drift don't change either.

I don't know too much about long range either

But i do know the wind drift and drop on a 180 grain sierra match king 7.62 round is consistent so as long as your sight is aligned you can then dial in your adjustments accordingly

Your proving my point. All a laser zero will do is align your scope with where the bore is pointing. The projectile when fired travels a predictable trajectory.....for the most part.

I will, however say that wind drift is not "consistent". Drop is consistent. Wind drift isn't. On very long range shooting the wind can actually be stronger or lighter at different points along the path. For example the wind may be light or non-existent from where the shooter is located......then out farther along the flight path the wind may be stronger due to topography or vegetation changes. Or visa versa.

 

[jkelly1229]

Your proving my point. All a laser zero will do is align your scope with where the bore is pointing. The projectile when fired travels a predictable trajectory.....for the most part.

I will, however say that wind drift is not "consistent". Drop is consistent. Wind drift isn't. On very long range shooting the wind can actually be stronger or lighter at different points along the path. For example the wind may be light or non-existent from where the shooter is located......then out farther along the flight path the wind may be stronger due to topography or vegetation changes. Or visa versa.

Physics is physics though... when i say consistent i mean a 10 mph gust of wind over a thousand yard shot consistently blowing left the whole time will drift every shot the same way.

Obviously no 2 shots are the same and everything

But a bullets reaction to the wind is consistent every time

 

[Rob Boudrie]

Physics is physics though... when i say consistent i mean a 10 mph gust of wind over a thousand yard shot consistently blowing left the whole time will drift every shot the same way.

Obviously no 2 shots are the same and everything

But a bullets reaction to the wind is consistent every time

You are neglecting the glint doppler effect. Holy crap - I just googled it, and it is a real thing (in radar though)

 

[strangenh]

2 city blocks is more like 400m in many modern cities where 8 blocks is a mile; they have alleys and half-blocks and so on between.

To the OP, I have had laser boresights get me right on target at 100m before - after adjusting for drop and bore axis - like spot on. But that was a stiff, heavy barrel and a light round, and 100m. Could I extrapolate? Sure. But without testing it as I did, I wouldn't know if the barrel whip was quite on; without knowing that, at 400m it could have been a good 6-8" off.

I think it was the author writing something to sound cool and technical.

 

[Dennis in MA]

read one in a Rapp book last night. Talking about taking fire from a .223 rifle but then some guy opens up on them with a SAW with the far more deadlier 5.56x45 that will shoot well over a mile.

 

[AHM]

read one in a Rapp book last night. Talking about taking fire from a .223 rifle but then some guy opens up on them with a SAW with the far more deadlier 5.56x45 that will shoot well over a mile.

Spoiler: Bitch, please

ETA: Florbert post in 3...2...1...