Hornady FTX coefficients- makes no sense

[mickbr]

Great bullets but one thing I never understood is the ballistic coefficients listed for their pistol bullets. The FTX bullets despite being designed with the benefit of a pointed bullet are listed with markedly worse ballistic coefficient than the standard hollowpoints. Either someone go their calculations wrong or it means the concept of that pointed tip failed.

In ascending order of 'aerodynamicness'

44 Mag bullets

225 Grain FTX BC .150
200 grain XTP BC .170
240 grain XTP BC .205

So a lighter hollowpoint has significantly better BC than the FTX?

The 357, 140 grain FTX is similarly ranked lower than the 158 grain XTP hollowpoint for B.C.

[GunnyMack]

Are they using the same BC formula, the G1 or the G7?
It could be they use the old G1 for the XTPs and the G7 for the FTX and that is where the discrepancy is?
I dunno, maybe a phone call to Hornady would get the answer.

[FLINT]

The only thing I can think of is that maybe the lighter weight of the plastic is working against it. So that the density is decreased because the volume is greater due to the increased length of the plastic tip but the mass isn't proportional to the increase in volume because of the lighter weight of the plastic?

It makes sense that the BC of the 357 158gr. is better than the 140 grain though because it's heavier. Heavier for caliber bullets should have higher BC.

[44shooter]

The problem is there is such a constraint on the overall length of a handgun bullet. That’s why the pointy ones are light for caliber. Also the pointy ones have less shank to make up for the longer ogive. That probably hurts bc more than having a blunt nose. Also you have to trim the brass way back to get a functional cartridge length. I just don’t see any benefit of it in revolver type rounds or even the straight rifle rounds like 444 or 45-70. The smaller caliber Leverevolution rifle bullets like 35 and under do show a substantial increase in bc without requiring shorter cases.

[FLINT]

Here's an article that makes your same observation about the 200 xtp BC being higher than the 225 FTX

https://www.americanrifleman.org/conten ... on-magnum/

The article does have a couple pics of the two bullets side by side. I don't know if my explanation has any merit, but you can see how much longer the 225 gr. bullet is than the 200 gr. to my eye, the difference in length doesn't seem proportional to the difference in weight. 25 grains is not much and that FTX bullet is much longer. so, possibly the FTX will experience more drag than the XTP and/or is less dense due to lower weight/volume ratio.

this conversation is purely academic though as the difference in the BC of the two bullets is negligible and the BC of both bullets is so low that it's basically not worth considering.

However, it is an interesting question. I think it probably goes to show that at least for pistol bullets, the whole pointy bullet thing is just hype. a way to sell more bullets. They are fairly light for caliber anyways and I'd want to start at 240 grains in 44 cal and go up from there.

[JimT]

Our culture in the U.S. is driven by marketing ... the newest .. the best ... the latest ... and often very subtly inferring the older established things are not nearly as good. So we see generations growing up without learning or knowing what has gone before.

As for the FTX .30-30 bullets I tried them and still have a partial box somewhere because they did not work for me as well as my old time-tested loads ... in my gun.

Now I don't mean to imply that improvements have not been made over the years or that all improvements are just hype. Test them. If they work well for you, great! If not, stick with what you know works.

And if you are still searching for the best load in your gun, try some of the older bullets and loads that you can still find. You never know until you try.

[mickbr]

I agree Jim, I dont buy or use the Ftx myself, it was why I queried folks attraction to them. Being they occupy more space in the case, the COAL is more finicky , and it seems their Ballistic Coefficient is worse, or at least not accurately represented. So what exactly do they do another bullet doesnt..
My own go to in 44 is the 240 grain XTP- expands from 1150fps-1800fps impact. and a B.C of .205 which equals some 30-30 bullets.

[mickbr]

Are they using the same BC formula, the G1 or the G7?
It could be they use the old G1 for the XTPs and the G7 for the FTX and that is where the discrepancy is?
I dunno, maybe a phone call to Hornady would get the answer.

You raise a good point there, maybe its two different systems at play. I know the science of ballistic coefficients can get complicated at different velocities. I just emailed Hornady.

[Galloway]

You raise a good point there, maybe its two different systems at play. I know the science of ballistic coefficients can get complicated at different velocities

I bet they know this and thats what green lighted the whole campaign lol

[AJMD429]

.
I think that ultimately the number they publish is going to be when they measured with the bullet being fired from a gun, as opposed to anything calculated based on its shape, so I guess we have to believe the public's figures are probably accurate, despite being counterintuitive.

I remember when I was into that sort of thing in the 1990s and home computers were just starting to be a thing I wrote some programs where I could shoot and a chronograph measure at 100 yards versus 10 feet come up which enabled me to calculate a ballistic coefficient that would apply to that bullet at those velocities. If the bullet did not transition the speed of sound I figured you could reasonably use that coefficient out another couple 100 yards and get really accurate predictions. Of course the problem was the predictions were to the 100th of an inch but my shooting skills were such all the math looked good on paper but didn't really help me hit my target much better. So in the end I would figure out what distance I wanted to sight in and if possible try to shoot some rounds at the longest range I might practically shoot at, just to verify holdover.