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Discussion Starter · #1 ·
STARTED at an even MORE pathetic 1500 fps, it's got less of a chance of hitting anything at 600 yds than does the 10" 223. At least, the 10" 223 can start a .300 BC bullet at 2450 fps. the .45-70 drifts in the wind like a balloon. :) Anyhitting it does on a man torso beyond 300m requires IDEAL conditions, and LUCK.
 

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And your point????? Please provide proof with your point!
 

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Go away, you've already has your ass handed to you on this. Just because it's no longer ont eh front page doesn't mean it went away.

Perhaps you should talk to these guys that shoot their .45-70s at 1000+ yards, and let them know they can hit anything at 600.

BTW, the .45-70 DROPS what it hits. The .223 from any barrel, much less a short-dick 10" pistol barrel, isn't good for drilling anything but paper at that range. But then, you never did have a clue on terminal ballistics.
 

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Ho hum, another recycled post. ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ
 

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wouldn't the heavier bullet be less prone to wind drift because of its greater inertia?
 

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krept,

The wind drift is a function of bullet shape, frontal area, velocity and mass, as well as wind speed.

If you would like, I will address wind drift at GBullet's Place.
 

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either way, it's all good.

I can see what you're getting at because I somewhat understand the effects of sectional density and in this case, for a perpindicular force like a crosswind, you have to measure the sectional density of the bullet using it's footprint 90 degrees from the norm (like the profile of a keyholing bullet). Mass and volume are factors as you stated, I just said "inertia" when I guess I meant momentum or technically resistance to a change in motion.

In my simplification (which is all I'm really capable of ;) ) I thought that out of all the possible factors involved, the .45-70 bullet andy is talking about would be less apt to be deflected by wind than a .223 bullet.

I mean, just in straight numbers if you say p=400gr x 1500fps the .45-70 has a momentum of 600,000 grFPS (or whatever the units are) and the 55gr [email protected] has a momentum of 134,750. So I guessed that even though the crosswind would have a larger surface area to apply force on with the .45-70, it's greater momentum would result in less drift, especially at greater ranges where the momentum of the .223 is decreasing at a greater rate... I think... :D

cheers
 

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Discussion Starter · #8 ·
nope. The greater profile of the .45 bullet gives the wind more surface to push against, and the longer a bullet is in flight, the longer that the wind has to push against it. Start such a blunt, no boattail bullet at 1500 fps, and it will need almost a full second to cover 300 yds. Start the .300 BC 223 at 2450 fps in a 10" 223, and it will cover 900 ft in about .40 second. So the wind will have TWICE as long to work on the .45 bullet, and it will have TWICE as big a surface to push-against, too. Which would you use to pull your sailboat across a lake, 1 mainsail, or two, hmm?\

There were NO rangefinders in the day of the 45-70, and the bullet drops SO badly that if you missjudge the range by 100 yds, you will shoot 6ft high or low at 1/4 mile or so. :)
 

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And yet people did (and do) hit consistantly at long range with the .45-70.
It's because they're RIFLEMEN, not pistol-range hoser cowards.
 

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krept said:
... I can see what you're getting at because I somewhat understand the effects of sectional density and in this case, for a perpindicular force like a crosswind, you have to measure the sectional density of the bullet using it's footprint 90 degrees from the norm (like the profile of a keyholing bullet). ...cheers
krept, the "keyhole" profile has nothing to do with it. The area that's important is the area as viewed from the front or rear. The SD does help the bullet resist change.

The greater the drag of the bullet, the more the wind will blow it.

The greater the mass of the bullet, the less the wind will blow it.

How can this be? Because the velocity of the bullet is so much greater than the wind velocity that the air flows from front to rear over the bullet, even in a strong crosswind.
 

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YES and that's what I'm asking. I didn't think about the flight times, btw... but... I clearly agree that the sum of forces vector wise work out so that the crosswind is much less significant overall. I think of it kinda like two vehicles going 2000MPH and 2005MPH. The latter is moving away from the former at 5mph; even though they're haulin ass, from the driver the separation occurs slowly. It might as well be as if one vehicle were parked and the other were moving with a v=5mph (assuming all else is equal).

Similar to the bullet, let's say that for every 100M that the bullet travels, it's moved 1mm because of the crosswind. For the overall 100M you use a sectional density as if it were a normal bullet to calculate the drag. But for the 1mm deviation due to the crosswind... the way I see it (could be totally wrong) you should be using the sectional density of the bullet as calculated from the perpindidular or "keyhole" position. I don't know what to call it otherwise.

It's like taking a paper plate and throwing it like a frisbee. cuts through the air fine, but if you hit a downdraft, it feels significant forces because yeah, it's a larger surface area the new force is acting upon. Therefore, doesn't the sectional density change? Much like it would if you shot the original bullet sideways out of the gun (surely it would penetrate a LOT less)?

Shit man, I'm getting lost in descriptions here. The way I see it is that there are two different sectional densities at play (longitudinal cross section vs. the "normal" cross section if you will of the .45 vs. the .223). Plus whatever odd Z vector the rotational (centripetal?) force that each bullet uses in addition to the momentum.

See, I'm gone now, I don't know what to say... but it sure as hell was fun pretending that I made sense :D

cheers
 

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please don't try to confuse GK iwth a concept like being a rifleman. It will just irritate the few brain cells he has left.

If you have ever seen some of the BPCR guys shoot at 5000 and beyon dyou know those cartridges can do some pretty impressive things.
 
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