Long Range Ballistics

[leo]

I brought up a point in another thread that a bullet with a higher sectional density, Ballistic coeficient will fly flatter farther than one with a lesser . My reloading data doesn't show much beyond 500yds. But in my data , a 160gr,btsp with a much higher b/c actually drops less at and assumably beyond 500yds than say a 140 gr. There is some genuine 1000 yd. marksman and reloaders on this site who know more about long range ballistics than I do , Please tell me if I am incorrect. From my 25 + years of reloading I was always under the impression that a lighter projectile sheds energy quicker than a heavier one

[Andrzej]

Originally Posted by leo

I was always under the impression that a lighter projectile sheds energy quicker than a heavier one

30-06 factory 220 gr will deliver 1000ft/lb up to 350 yards,
150gr up to 400y.
BUT
225gr from 338 Win Mag will carry 1000 ft/lb up to 700 yards.

Leo get yourself one of the ballistic programs , I use Remington Shoot, free from Remington site it will let you see what happens up to 1000 yards /meters trajectory, energy,
I would play with this and confirm at the range.

You can play with numbers.

[lclund1946]

Originally Posted by leo

I brought up a point in another thread that a bullet with a higher sectional density, Ballistic coeficient will fly flatter farther than one with a lesser . My reloading data doesn't show much beyond 500yds. But in my data , a 160gr,btsp with a much higher b/c actually drops less at and assumably beyond 500yds than say a 140 gr. There is some genuine 1000 yd. marksman and reloaders on this site who know more about long range ballistics than I do , Please tell me if I am incorrect. From my 25 + years of reloading I was always under the impression that a lighter projectile sheds energy quicker than a heavier one

I suggest that you get yourself a ballistics program such as RCBS Load and do some comparisons. What you are suggesting is kind of like the myth that lighter bullets drift less in the wind than heavier ones. When you start doing some comparisons you will find that Ballistic Coefficient and Velocity determine Terminal Energy, bullet drop and wind drift.

Here is a comparison of a 140 grain and 168 grain bullet that will shed some light on the subject:
BERGER - 6.5mm, 140 VLD, BC .633, MV 3200fps, ME 3182.9 ft. lbs., 1000 yd energy 1052.8 ft. lbs., 1000 yd drop 216.49" and 1000 yard drift in a 10 mph wind is 53.18".
BERGER - 7mm, 168 VLD, BC .617, MV 3200fps, ME 3819.5 ft. lbs., 1000 yd energy 1223.4 ft. lbs., 1000 yd drop 219.37" and 1000 yard drift in a 10 mph wind is 54.98".

If the BC would have been the same then the 1000 yd drop and wind drift would have been exactly the same. But because the 6.5 bullet has a slightly higher BC it drops less and has less wind drift. As far as shedding energy faster the 6.5 bullet retained 33.07% of its energy while the 7mm bullet retained only 32% of its energy. If the BC would have been the same then the percentage retained energy would have been the same. As the 7mm bullet started out with more energy at the muzzle it has a corresponding higher terminal energy. Along with that comes more recoil.

[leo]

Okay what you guys suggest makes some sense. But a 139 gr 7mm hornady vs a 162 gr 7mm hornady ,at 500 yds the difference in bullet drop starts to favor the 162 . Does that not mean that at say 800 yds the actual flight arc is less pronounced in the heavier, higher bc bullet. Will the bullet drop not be less than the 139 gr,both assuming a 200 yd 0 . The 162 gr at 3000fps, the 139gr at 3200fps or max loads for the individual gun ?

[Andrzej]

Leo

go to

http://www.gsgroup.co.za/download.html

Download this presentation (it is on my Desktop all the time)

there is a lots of information and this will answer your questions + some.

Andrew

[bingo1010]

higher bc bullets will drop less/ retain more energy than lesser bc bullets. that about sums it up. you can move a lighter bullet faster and this will "mask" the difference for a short while but the farther out you go the more the diff will be....totally favoring the higher bc bullet. under 500 you won't see much diff between them.

[SHORTMAG]

Take a 300 win mag shooting two 180 gr reloaded rounds at 500 yards. Using a PSP tip in one case and a Ballistic tip in the other.....the ballistic tip will have approx 450+- Foot pounds MORE energy than the PSP at that distance. That's quite a bit more by just swapping a lowly old tip!!!

Originally Posted by bingo1010

higher bc bullets will drop less/ retain more energy than lesser bc bullets. that about sums it up. you can move a lighter bullet faster and this will "mask" the difference for a short while but the farther out you go the more the diff will be....totally favoring the higher bc bullet. under 500 you won't see much diff between them.

Exactly. It all comes down to time of flight. The higher BC bullet gets there faster because it retains velocity better. Less time in the air means gravity has less time to act upon it which means less drop. Gravity has the same effect regardless of the projectile BC, size, weight or shape, it's just the one with the higher BC gets there faster....at very long ranges of course.

It's basically the same thing with a side wind. The faster it gets there, the less it gets blown off track.

[leo]

Originally Posted by sheephunter

Exactly. It all comes down to time of flight. The higher BC bullet gets there faster because it retains velocity better. Less time in the air means gravity has less time to act upon it which means less drop. Gravity has the same effect regardless of the projectile BC, size, weight or shape, it's just the one with the higher BC gets there faster....at very long ranges of course.

It's basically the same thing with a side wind. The faster it gets there, the less it gets blown off track.

Thank you, I was sure I was right (all this grey hair should trap in some knowledge).

[elkhunter11]

Thank you, I was sure I was right (all this grey hair should trap in some knowledge)

You would have been 100% right if you had not mentioned sectional density,as sectional density is not a factor in calculating trajectory.If you compare two bullets of equal diameter and weight,they will have an identical sectional density,but they may have vastly different ballistic co-efficients,and therefore vastly different trajectories.To further prover the point,a 180gr round nose will almost always have a much lower ballistic co-efficient than a 165gr pointed boattail of the same diameter,but despite the higher sectional density of the 180gr bullet,it will shed velocity much quicker and it's flight path will fall away much quicker.

[PoppaW]

If your cheap like me try JBM calculations. Its free and more info on trajectories than you know what to do with.

[leo]

Originally Posted by elkhunter11

You would have been 100% right if you had not mentioned sectional density,as sectional density is not a factor in calculating trajectory.If you compare two bullets of equal diameter and weight,they will have an identical sectional density,but they may have vastly different ballistic co-efficients,and therefore vastly different trajectories.To further prover the point,a 180gr round nose will almost always have a much lower ballistic co-efficient than a 165gr pointed boattail of the same diameter,but despite the higher sectional density of the 180gr bullet,it will shed velocity much quicker and it's flight path will fall away much quicker.

Some day when I grow up ,I want to be as smart as you!

[ACKLEY ABE]

Originally Posted by SHORTMAG

Take a 300 win mag shooting two 180 gr reloaded rounds at 500 yards. Using a PSP tip in one case and a Ballistic tip in the other.....the ballistic tip will have approx 450+- Foot pounds MORE energy than the PSP at that distance. That's quite a bit more by just swapping a lowly old tip!!!

Somebody got a list of co-efficients, Rem 180 psp and Nosler 180 Bal tips. We'll us 3050 fps as a base just to compare apples to apples. I'm at work, no manuals handy. This math doesn't look quite right.

[SHORTMAG]

Hey Abe...I read that on some gun forum/site I was scrolling thru one sleepless nite....a few years ago..looking for "other" good loads for my 300WSM....wrote it down in my computer desk scribbler.....it actually says a 180 gr partition {{not psp...sorry...the PSP's do have a higher BC(.416) than the partitions}} . So between a 180 gr Partition (BC 361) , and a 180 gr Accubond (BC 507).......muzzle vel 3080......Muzzle Energy 3603 ft lbs..... @ 500 yds...the partition has 1313 ft lbs left...and the Accubond has 1765 ft lbs left. I can't say for certain what site it came from, so I just checked with Federals Balistic program and looked at the data for it's factory loaded stuff.........this is what they're showing for...
Federal Premium Vital Shock......180 grain loads....300Win Mag...

accubond...ME...3503 lbs...500 yds...1763 lbs
partition...ME...3503 lbs.....500 yds...1295 lbs

a difference of 468 ft lbs. I was just adding a little more proof that the higher BC bullets definately shine at the longer distances. That info was what made me stick with the BT/AccB Noslers!
***EDIT IN ***...The 180 gr Speer PSP also loaded in Fed Prem V/S Bullets has a BC of .439, and this calculates into...1570 ft lbs retained @ 500 yds...a diff of ONLY 193 ft lbs !...a wee bit closer.

[Rantastic]

I believe i am the one leo was talking with about bullets and i thought the arguement was that a heavier bullet will fly flatter due to its higher bc. I like using 140's for their flatter shooting over the 175's and I insist that they will not drop as fast as heavy bullets because u can shoot them faster.

The thing u arent considering is the smaller bullets can be fired at least 300fps faster right from the start so yes they lose velocity faster but they start with so much more that it seems to me to mroe than compensate for the lack of bc.

I hate to sound like im trying to win an argument here but Im just going by this ballistic calculator but if u use one that shows im wrong then let me know cuz im just going by what i can see here.

http://biggameinfo.com/BalCalc.aspx

And ill telll you the info i entered... my 140g bergers hunting VLD have a cal. of .284, BC of .486 and at 3000ft above sea lvl get a speed of muzzle speed of 3300fps(crono tested) from 70gr of reloader 22(hottest safe load in my manual) This is my actual hunting load.
zero range 200 intervals 100 Thats all i changed and i got
30 inches of drop at 500
51 at 600
79 at 700
115 at 800
160 at 900
216 at 1000 yards

now using the same cal, brand and type of bullet,(bergers hunting VLD) when i change only the bullet weight to 180 the bc up to .659 and the muzzle speed down to the safest hot load in my manual to get 3000 fps muzzle then i get drop of
34 inch drop at 500
57 at 600
87 at 700 yrds
124 at 800
170 at 900
226 at 1000
That to me says the lighter bullet leaving the train at the faster speed drops less over time... But with enough (over 1500ft/lbs energy) ethical hunting energy upon hitting at 600yards. Do we really need the larger bullet?
The only reason i would use the heavy bullet is the wind deflection would definitly be less and the bullet would hit with more kinetic energy. No arguments on those but the lighter bullet because it can be fired so much faster will not drop as much. At least as my findings show. Does anyone see something im missing about the drop charts facts? if i have entered something wrong please inform me as im open to admitting im wrong if it can be shown to me.

[Rantastic]

just to add i punched in a 10 mile an hour wind for both and found for my 140's
the wind deflection at 500yards to be 13.9 inches and at 20 mph winds 27.8 inches
when entering all the 180 info i get 11.3 inches and at 20mph winds 22.5 inches

so at 500 yards in 10 mph winds the diff is only 2 inchs of deflection... Thats alot less than i figured it would be. and at 20 mph wind, i would nto be shootin since 2 feet of deflection is above my shooting ability right now so i would not be taking the shot. but still only 5 inches difference at 500 yards for the high bc bullet.
The main difference i see is in the energy.
The 180 can still hit above 150 ft/lbs out just past 800 yards so u could stretch ur barrel that much more but for practical hunters. who really shoots at elk/moose at 800 yards?

Sorry again leo cuz im sure all this makes me come off like a d i ck but i promise u im just trying to do all my homework and learn this stuff right.

lclund i dont think using 2 diff cal bullets is a fair comparison but i get the point u were trying to illustrate for leo.

Originally Posted by crazy_fool1

I believe i am the one leo was talking with about bullets and i thought the arguement was that a heavier bullet will fly flatter due to its higher bc. I like using 140's for their flatter shooting over the 175's and I insist that they will not drop as fast as heavy bullets because u can shoot them faster.

The thing u arent considering is the smaller bullets can be fired at least 300fps faster right from the start so yes they lose velocity faster but they start with so much more that it seems to me to mroe than compensate for the lack of bc.

I hate to sound like im trying to win an argument here but Im just going by this ballistic calculator but if u use one that shows im wrong then let me know cuz im just going by what i can see here.

http://biggameinfo.com/BalCalc.aspx

And ill telll you the info i entered... my 140g bergers hunting VLD have a cal. of .284, BC of .486 and at 3000ft above sea lvl get a speed of muzzle speed of 3300fps(crono tested) from 70gr of reloader 22(hottest safe load in my manual) This is my actual hunting load.
zero range 200 intervals 100 Thats all i changed and i got
30 inches of drop at 500
51 at 600
79 at 700
115 at 800
160 at 900
216 at 1000 yards

now using the same cal, brand and type of bullet,(bergers hunting VLD) when i change only the bullet weight to 180 the bc up to .659 and the muzzle speed down to the safest hot load in my manual to get 3000 fps muzzle then i get drop of
34 inch drop at 500
57 at 600
87 at 700 yrds
124 at 800
170 at 900
226 at 1000
That to me says the lighter bullet leaving the train at the faster speed drops less over time... But with enough (over 1500ft/lbs energy) ethical hunting energy upon hitting at 600yards. Do we really need the larger bullet?
The only reason i would use the heavy bullet is the wind deflection would definitly be less and the bullet would hit with more kinetic energy. No arguments on those but the lighter bullet because it can be fired so much faster will not drop as much. At least as my findings show. Does anyone see something im missing about the drop charts facts? if i have entered something wrong please inform me as im open to admitting im wrong if it can be shown to me.

Yes and no. The higher BC of the heavier bullet will ultimately prevail but in the case you've highlighted, it would take more than 1,000 yards for that to happen. As you point out, it's critical to see what you are and aren't gaining with your particular load in real world hunting situations. With other bullet styles, the distance it takes for heavier, higher BC bullets to pass their lighterweight counterparts is not nearly so far.

[Bobby B.]

Don't have any manuals in front of me but I do recall the basic differences of lighter vs heavier bullets. I'll use the 140 and 160 loads out of a 7RM for comparison. As Randy stated, the lighter bullet will start off with a greater MV than the heavier bullet. Obviously, the lighter bullet has initial speed in it's favor. The heavier bullet has an advantage with a higher BC than the lighter bullet. At some point, and it's further than 500 yds, could be around 1000 but I'm not sure offhand, the higher MV of the lighter bullet trumps the higher BC of the heavier bullet and the 140 grain bullet drops less than the 160. As the distance increases, the greater BC of the heavier bullet provides greater velocity retention over the lighter bullet and the advantage of velocity is now in favor of the heavier bullet. However, the heavier bullet is always deflected less by the wind. Because bullet drop is easier to compensate for than is wind deflection, many hunters choose the heavier bullet and all long range competition shooters do.

Bobby B.

[Rantastic]

For sure, other bullets with much lower BC's say older technology bullets with round noses, the gap would be lower and maybe even less than 500 yards.

Even in lower cal bullets i could see it happeneing much sooner but in real world situations for big game, with my particular bullets and loads there isnt a reason for me to use the big ones unless i was considering hunting at 800yards. And that aint happening anytime soon

[leo]

Originally Posted by elkhunter11

You would have been 100% right if you had not mentioned sectional density,as sectional density is not a factor in calculating trajectory.If you compare two bullets of equal diameter and weight,they will have an identical sectional density,but they may have vastly different ballistic co-efficients,and therefore vastly different trajectories.To further prover the point,a 180gr round nose will almost always have a much lower ballistic co-efficient than a 165gr pointed boattail of the same diameter,but despite the higher sectional density of the 180gr bullet,it will shed velocity much quicker and it's flight path will fall away much quicker.

For the record , Ballistic coeficient is a calculation of a bullets sectional density as well as the shape of the projectile. The bullet with the higher sectional density will always have a higher ballistic coeficient than a lighter bullet of same caliber, the same design .The higher ballistic coeficient equates to trajectory. Or did I need more correcting? I don't profess to be an expert , but I'm not a $$%# for brains either!

[elkhunter11]

For the record , Ballistic coeficient is a calculation of a bullets sectional density as well as the shape of the projectile. The bullet with the higher sectional density will always have a higher ballistic coeficient than a lighter bullet of same caliber, the same design .The higher ballistic coeficient equates to trajectory.

Your original post made no mention of bullets being the exact same shape and design.As a result of the wording you used,there was an implication that just because a bullet has a higher sectional density it would have a higher ballistic co-efficient,which is not always the case.That is the point that I was making.

[Bobby B.]

Bullet weight, SD and BC are all correlated. For a given bullet design, ie Berger VLD, the greater the bullet weight, the greater the SD and the higher the BC. Therefore, comparing, for example, a 7mm 140 VLD to a 7mm 168 VLD, the heavier 168 grain bullet has a greater SD and a higher BC due to its greater weight.

Bobby B.

[elkhunter11]

Bullet weight, SD and BC are all correlated. For a given bullet design, ie Berger VLD, the greater the bullet weight, the greater the SD and the higher the BC. Therefore, comparing, for example, a 7mm 140 VLD to a 7mm 168 VLD, the heavier 168 grain bullet has a greater SD and a higher BC due to its greater weight.

Usually,but not always.Try comparing a Barnes 7mm 140gr TSX to a 7mm 160gr TSX.How about a .308" 180gr TSX,and a .308" 200gr TSX.In fact it is quite common with the Barnes TSX line.

[leo]

Originally Posted by elkhunter11

Your original post made no mention of bullets being the exact same shape and design.As a result of the wording you used,there was an implication that just because a bullet has a higher sectional density it would have a higher ballistic co-efficient,which is not always the case.That is the point that I was making.

Nor did I suggest I was comparing a round nose to a pointed boattail or conventional shank, that assumption you made on your own. All I suggested was that a 160 gr bullet from a 7mm would fly flatter farther,and retain more energy than a 139-140 gr 7mm projectile . If different bullet designs were used it would not be a fair comparison. I was fully aware that you would not see a significant difference in trajectory until past 500 yds. In fact up to that point the lighter projectile would seem to be the flatter. I believe I have made my point!

[Bobby B.]

Originally Posted by elkhunter11

Usually,but not always.Try comparing a Barnes 7mm 140gr TSX to a 7mm 160gr TSX.How about a .308" 180gr TSX,and a .308" 200gr TSX.In fact it is quite common with the Barnes TSX line.

I did the comparisons, the 7mm 140 is a boattail, the 160 a flatbase. The .308 180 a boattail and the 200 a flatbase. Obviously, these are not comparisons of bullets of the same design. My statement directed at correlation of weight, SD and BC still holds true.

Bobby B.

[leo]

Nice Kudu Bobby B.

[elkhunter11]

I did the comparisons, the 7mm 140 is a boattail, the 160 a flatbase. The .308 180 a boattail and the 200 a flatbase. Obviously, these are not comparisons of bullets of the same design.

They are all Barnes TSX bullets,not identical but of the same basic design and close enough for Barnes to give them the same name.

[Bobby B.]

I'm not sure who you're attempting to fool, but stop while you're not too far behind. You're misdirection is glaring. Try to be a bit more factual.

Bobby B.

[elkhunter11]

I'm not sure who you're attempting to fool, but stop while you're not too far behind. You're misdirection is glaring. Try to be a bit more factual.

Is it,or is it not a fact,that the Barnes bullets that I mentioned,are all members of the TSX family.All are monometal bullets,with the same nose design,and all have similar grooves on the shank,although some have more weight to the rear of the shank to reduce the overall length.That extra weight,because of it's placement,while increasing the sectional density of the bullets,also lowers the B.C. of the bullets.

Is it,or is it not a fact that if I gave you only the velocity and sectional densities of three bullets,you could not know for a fact which of the bullets will produce the flattest trajectory?

Is it,or is it not a fact,that if if I gave you only the velocity and weight of three bullets,you could not know for a fact which of the bullets will produce the flattest trajectory?

Is it,or is it not a fact,that if if I gave you only the true muzzle velocity and the true ballistic coefficients of three bullets,you could know for a fact which of the bullets will produce the flattest trajectory?

The fact is that while the mass and cross section of a bullet are two of the elements used to calculate the B.C.,you can't accurately predict B.C. or trajectory based on either one or on both.They mean nothing without knowing the bullet shape.

Why do you suppose that Barnes chooses to make the heavy for caliber TSX bullets with more weight at the rear of the shank?Could it be because if they simply make that heavy bullet longer,that it won't stabilize in most rifles?Now what do you suppose happens to the B.C. of a bullet if it begins to yaw and does not stabilize?Accuracy will usually be reduced,but the B.C. will drop considerably as well.

[Bobby B.]

Elkhunter

What is fact is you suggested comparing flat base bullets to boattail bullets. In affect, you suggested comparing apples to oranges. What I initiallly stated what quite straightforward, it goes like this "when comparing bullets of like design ( not flatbase vs boattail), there is a correlation between bullet weight, SD and BC". for some odd reason I'd prefer for you to explain, you suggested comparing bullets of one design to bullets of a different design to disprove my statement. Please go on. Be specific, demonstrate how to bullets of the same design, the heavier bullet will not provide greater SD and greater BC.

Bobby B.