200 grain verse 180 grain bullets
OK, this is going to sound like a really dumb question. I always figured when comparing bullets in the same caliber that the heaver grain bullets would have more foots pounds of energy "knock down power".
Last night I was looking at Federals ammo page and read the following.
When comparing the 300 win mag 200 grain Premium Trophy Bond Bear-Claw and the 300 win mag 180 grain Premium Trophy Bonded Bear-Claw the 180 grain was faster from muzzle to 500 yards, had more foot pounds of energy from muzzle to 500 yards, dropped less from muzzle to 500 yards and so on.
So what is the advantage of the 200 grain bullet over the 180 grain?
Speed retention at range is going to depend on both weight and bullet shape (ballistic coefficient). Obviously that particular 200 is not as well shaped for reducing drag and holding velocity. Potentially a 200 will penetrate better than a 180 depnding on bullet construction (sectional density). In my limited comparisons of 180s and 200s of the same construction (Nosler partitions), the weights are so close that there seemed to be little difference in penetration. It was the old "semi-pointed" 200 grainers rather than the newer variety, and they didn't shoot nearly as flat as the newer pointed version. I bet with the new ones the 200 would definitely shoot flatter at long range, but would still only offer a slight advantage in penetration.
When you start comparing different brands, shapes and construction of bullets it's kind of like comparing politicians' promises before an election. Make your best call, but the "spin" put on by corporations and supporters gets awfully deep.
The term "knock down power" is one of the most spun terms in the ballistic field. Some folks even use a different formula (Taylor Knockout Index or TKO) to try to calculate it separately from traditional energy calculations.
[quote=lovefishing] I always figured when comparing bullets in the same caliber that the heaver grain bullets would have more foots pounds of energy "knock down power".
Usually, in similar constucted bullets the heavier or longer bullet will have slightly less foot pounds of energy because the bullet has to be seated a little deeper into the case (ie. less powder). However, the longer bullet usually has a significant increase in aerodynamics (ballistic coeficeint) to actually catch up and be travelling faster at longer ranges and therefore, more energy at say 200 or 300 yards.
The reason I tend to like heavier bullets, is because it slows the bullets starting velocity to what I (and many others) consider to be a safer velocity to avoid bullet failure in case of a very close shot ( which is what I like, the closer the better). Just as BrownBear said that particular 200 is not as well shaped.
I'm not sure that starting velocity will be that big of an issue with the Trophy Bonded bullet.
Energy = Mass X (Velocity Squared)
Energy will be affected much more by velocity than bullet weight. Therefore just because a bullet is heavier, does not mean it will have more energy unless it is also traveling at the same or faster speed than the lighter bullet. Bullet contruction and velocity have much more to do with "knock down" than the weight.
The only difference between the two bullets is one is a 180 grain and one is a 200 grain. Both made by the same company, same type of bullets etc. But the 180 is faster, more foot pounds of energy, drop less at longer distance ect. So my questions would be...what is the advantage of using the 200 grain over the 180 grain?
It doesn't sound like the 200 has any advantage in flight ballistics, but the question is what are you going to do with it? The 200 may have better wound ballistics, which you can't tell from any charts.
[quote=lovefishing]The only difference between the two bullets is one is a 180 grain and one is a 200 grain. Both made by the same company, same type of bullets etc. But the 180 is faster, more foot pounds of energy, drop less at longer distance ect. So my questions would be...what is the advantage of using the 200 grain over the 180 grain?
Probably not much. Hunting deer, caribou, sheep, Elk, I would say definitely not much, or none. However, myself being somewhat hyperanalytical, if I might run into a grizzly, or I wanted to be able to shoot at a moose straight on, or from a hard quartering shot, I would opt for the 200 gr. Troghy Bonded with the expectation of a little bit more penetration. How?, you say. Even though the 180 has more speed and energy, the 200 will probably open up less (lower velocity) and therefore penetrate more (ie. deeper). Good bullet traits when shooting at tough game.
Factory ammo ballistics:
Originally Posted by lovefishing1965
Factory Norma 180-grain A-Frame, rifle sighted +1.7" at 100 yards
Muzzle = 2920 fps, 3409 foot-pound
100 yd = 2687 fps, 2887 foot-pound
200 yd = 2466 fps, 2432 foot pound. Bullet drop = 0.0"
300 yd = 2266 fps, 2035 foot-pound. Bullet drop = -7.4"
400 yd = 2056 fps, 1690 foot-pound. Bullet drop = -21.6"
500 yd = 1867 fps, 1393 foot-pound. Bullet drop = -44.1"
Remington 200-grain A-Frame, rifle sighted +1.8" at 100 yards
Muzzle = 2825 fps, 3544 foot-pound
100 yd = 2595 fps, 2889 foot-pound.
200 yd = 2376 fps, 2506 foot-pound. Bullet drop = 0.0"
300 yd = 2167 fps, 2086 foot pound. Bullet drop = -8.0"
400 yd = 1970 fps, 1722 foot-pound. Bullet drop = -23.5"
500 yd = 1783 fps, 1412 foot-pound. Bullet drop = -47.9"
If you handload HOT and can drive the lighter bullet faster, maybe then you can offset the energy level the 200 grainer has over the lighter one, but with similarly constructed bullets loaded within the safe reloading parameters such as those two factory ones above, the heavier one will always have more energy downrange. However, within 200 yards I would prefer the heavier one of the two, because it has greater SD than the lighter one, and the potential for deeper penetration. At much closer range, since the lighter one is traveling faster, it has the potential for faster expansion than the heavier one, and therefore shallower penetration than the heavier one. With solids it probably makes no difference, however.
What some folks fail to realize is that of two similarly constructed bullets (same caliber, too), the heavier one keeps its momentum a little longer than the lighter one out to perhaps 250-300 yards, even though the lighter one is more aerodynamic. That's why they strike the target within a couple of inches from each other. A long range the lighter one travels through the air flatter by a few inches, but a shooter who knows his bullet's trajectory can simply hold-over a little to compensate for bullet drop, and still hit the target with the heavier bullet with a force that is very similar to that of the lighter bullet.
180 verse 200
Thanks for the information on the remington. On the Remington information your provided it shows the 200 grain with more foot pounds of energy. However, if you look at Federals 180grain Prem Trophy and the 200 grain Prem Trophy is shows the 180 grains with "more" foots pounds of energy from muzzle all the way out to 500 yards. So it is kind backwards from what Remington showed in your post. I guess that is what I am confussed about.
Are you sure you are not looking at a Federal 180-grain TB HE against a standard load with 200-grain TB bullet?
Originally Posted by lovefishing1965
The ballistics, one with 180-grain TB HE, and the 200 TB are very different. While the 180 High Energy load produces 3100 fps, and 3840 foot-pound at the muzzle, the standard load with a 200-grain TB only produces 2800 fps, and 3480 foot-pound at the muzzle. That gives the 180 grainer TB 200 fps over the 200-grain TB. In this case the speed of the lighter one has been boosted to the point that it offsets the energy advantage of the similarly constructed but heavier bullet. But if the 200 grainer is loaded by the factory to HE velocity, then it would produce somewhere around 2930 fps at the muzzle, coupled to higher energy than the 180-grain TB HE.
I haven't looked at the loads you have mentioned, but keep in mind that Federal and Hornady create certain loads with high energy powders to boost velocity. Maybe that's the case for the 180-grain load you have mentioned. Take a look at the difference in velocities at the muzzle: if the 180 grainer is somewhere over 200+ fps faster than the 200 grainer, then the 180 grainer is a fast load compared to a 200-grain standard load. In this case the 180 grainer's speed can offset the energy advantage of the heavier one.
Please post the velocities from the charts you are looking at.
Note that in the example provided by Ray, the 180 is going slower relative to the 200 (based on weights). In order for the two to be equal in energy, the 180 would have to be pushing 3,139 fps.
Federals web site
Reference to the 180 grain and the 200 grain Prem Trophy Bonded Bear Claw in the 300 win mag:
Velocity in feet per second:
100 yards= 2706
200 yards= 2465
300 yards= 2237
400 yards= 2022
500 yards= 1819
180 grain "Energy in foot pounds"
100 yards= 2927
200 yards= 2430
300 yards= 2001
400 yards= 1634
500 yards= 1323
180 grain "Trajectory"
300 yards= -7.4
400 yards= - 21.7
500 yards= -44.6
Same bullet in the 200 grain
100 yards= 2476
200 yards= 2263
300 yards= 2060
400 yards= 1868
500 yards= 1689
200 grain " Foot pounds"
100 yards= 2723
200 yards= 2274
300 yards= 1885
400 yards= 1551
500 yards= 1267
200 grain "Trajectory"
100 yards= + 1.6
200 yards= zero
300 yards= - 7.4
400 yards= - 21.7
500 yards= 44.6
To me it just does not make any sence
Look at it this way: If the 180 and 200 were both started at the same MV, the 200 would win hands down. In this particular case the velocity loss in moving to the 200 negates that.
In reality, the weight difference between the two is too small to be significant. If anyone claimes a REAL difference in actual killing power on game, they need to spend more time shooting game and less time typing. Pick whichever shoots best in your gun and be happy that you have a great load. Now all you have to do is shoot it lots so you can land it in exactly the right spot when the chips are down.
For a pure academic exercize, compare that 200 with a much lighter bullet than 180. Though the faster bullet starts much faster, it will lose velocity much faster than the 200 and not shoot as flat as range stretches. Comparing the 180 and 200, eventually the same will happen but due to the similarity in weights it will be a long ways out there before it does- way beyond hunting ranges anyway. With a 200 compared to a 110, on the other hand, you are likely to see significant differences well within hunting range.
I see what you are talking about now. It seems to me that the 200-grain bullet was loaded very mild at 2700 fps. That's why you see the greater energy on the 180-grain bullet's table. A standard factory load with a 200-grain bullet for the .300WM is from 2800 to 2830 fps fps at the muzzle, although Nosler loads their 200 grainer SP at a mild 2,789 fps. The factory standard velocity for the 180 grainer is just a tad faster than that of the 200 grainer, except for special loads. For example, Remington is producing reduced load ammo for close range hunting.
It makes perfect sense, but you have to think mathematically.
Originally Posted by lovefishing1965
Note the 180 is traveling 260 fps faster at the muzzle. The weight difference is only 20 gr. When you do the math (E=m*v*v), the energy of the 180 is higher within the first 300-yards due to the greater speed. If you then compare the relative speeds throughout your trajectory, you'll also notice that the 180 loses speed faster than the 200 with the difference between the two cut in half at 500-yards.
Also, the energy of the 200 is greater beyond 300-yards. You're reading the chart wrong as the energy of the 2 bullets is practically equal at 300-yards where the 200 then takes over. The heavier bullet will retain energy longer, as everyone has been saying. If the two started at the same muzzle velocity, then the heavier bullet would win all the way out.
After your PM, I went and looked at the Federal web data myself. There are a few typos in the info you listed vs. the website and the energy of the 200 does in fact remain less than the 180 out to 500 yards, but not by much (I must also have misread your data while scrolling up and down to compare the figures). Also, you listed the same trajectory data for both rounds, but the drop figures for the 200 grain should be "2.1, 0, -8.9, -25.9, -53.3" per the federal chart. I've attached the graphical charts for visual comparison of velocity and energy.
The short answer to all of this is that the lighter bullet shows more energy simply because it is loaded hotter and traveling much faster. Speed has more affect on energy than the weight. The heavier bullet is starting out slower, but retains more energy for a longer period of time. This is because the larger mass resists losing speed to air resistance more so than the lighter bullet of the same frontal profile. That's all there is to it.
velocity and ftpnds aside the heavier bullet may be more accurate and reliable. Im thinking wind deflectionn here. my 300 wnmag shoots 200grns better than 180 but i use the 180 anyways just cuz it suits me.