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.340 Wby Ammo

.340 Wby Ammo
« on: March 13, 2009, 08:32:12 AM »
As I stated in the New Bullet Choices thread, I would really like to see Weatherby replace the 225gr TSX with a 225gr TTSX if possible. That leads me to a few questions I would appreciate any answers to:

All bullet types by a given bullet manufacturer for a particular caliber seem, as is logical, to increase in ballistic coefficient as they increase in weight (and thus length). One exception I can find in the Barnes .338 TSX bullets:

185gr = 0.352 BC
210gr = 0.404 BC
225gr = 0.386 BC
250gr = 0.425 BC
http://www.barnesbullets.com/products/rifle/tsx-bullet/

For the .338 TTSX bullets:

160gr = 0.342 BC
210gr = 0.482 BC
225gr = 0.514 BC
http://www.barnesbullets.com/products/rifle/tipped-tsx-bullet/

It is odd to me that the BC drops off for the 225gr TSX over the shorter 210gr bullet. Do you experts think it's a misprint or something else? If it's a misprint, I would like to know, so I could calculate (http://www.handloads.com/calc/) the actual downrange ballistics of the Weatherby 2,970 fps MV loading. If it is not a misprint, I hope Weatherby decides to load, instead, the 225 TTSX bullet. Using the calculator linked above, the difference between a 0.386 BC and a 0.514 BC 225gr bullet leaving the muzzle at 2,970 fps sighted in at 300 yards is that the TTSX would hit four inches higher and with FIVE HUNDRED more foot-pounds of energy at 500yds (2,239 fpe for the TTSX vs. only 1,749 fpe for the TSX at 500yds). That's a big difference.

Also, the Weatherby "Ballistics Specifications" pdf states that the .338-.378 225gr loading uses the same 225gr Barnes TSX, but lists a BC of 0.482. Is that a misprint? I know of no 0.482 BC 225gr Barnes TSX in .338 caliber. The only 225gr Barnes TSX in .338 caliber listed on Barnes' website is the 0.386 BC. I am hoping for answers to the above so that I can decide whether or not to use the Wby 225gr load in my .340, and if I do, I need to know how fast it will be going and how far it will drop at longer ranges.

Thanks in advance for any comments.
« Last Edit: March 13, 2009, 08:35:40 AM by MarineHawk »

James

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Re: .340 Wby Ammo
« Reply #1 on: April 06, 2009, 04:02:05 AM »
While I truly admire your eye for detail and your desire for accuracy, my OPINION is that you are much too concerned with the theoretical part of shooting. Ballistics tables and ballistic coefficients are guidelines, and they cannot tell you all you need to know for your long range shooting. One reason is that there are different ways to calculate the bc of a bullet, and all of the manufacturers have their own calculations with their own numbers, so as you noticed, even the bullet makers may use different numbers in their calculations for the same bullets.

I love my .340, and like you I wanted to know exactly what my bullet was going to do so that I could calculate my long range ballistics accurately. I shoot the 225 grain Nosler Accubond bullets and like to shoot to a thousand yards or a bit more from time to time, and I found that using the manufacturers numbers did not deliver the accurate calculations I expected, especially at longer distances. The figures were close, but just not close enough. I became a tad frustrated, but soon decided that since my bullet would not do what my calculations predicted, the only way that I would ever get the accuracy from my calculations I wanted was to adjust the figures so that my calculations matched my bullet flight.

I zeroed my rifle at 100 yards, and then began shooting at much longer ranges, making notes of the necessary adjustments (dope) to zero my scope at those ranges, and using the factory listed bc and making minor adjustments in my estimated bullet velocity, I began to run the numbers again in the ballistics calculator until my calculations closely matched my actual ballistics.

In the end I determined that I had to make a 20 fps reduction in the predicted bullet velocity (predicted from reloading tables) to make my calculations fit my actual ballistics, but now my charts are very accurate for my gun. I use 88 gr. of Reloader 22 powder, and it was predicted that I would get 3035 fps from that load, but the velocity that worked best in my calculator turned out to be just 3015 fps.

Now my ballistics charts are accurate farther than I care to shoot, and I like shooting long distances.

Good shooting to you! If you have any questions I would be more than happy to share what I know, and I'd be happy to send you my ballistics chart if you will send me e-mail at jlbox@msn.com.

 





« Last Edit: April 06, 2009, 04:06:53 AM by James »
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Re: .340 Wby Ammo
« Reply #2 on: April 06, 2009, 11:39:50 AM »
Oregon Jim:

Thanks for your comments. Thanks for the offer for the charts and other info. I will send you an e-mail.

I don't deny that I am a little obsessed with the numerical aspects of shooting trajectories, but let me give you my basic context. I bought the .340 because it has the capability to deliver a big punch both up close and at great range. I think that the Wby factory 250gr loads certainly accomplish this nicely, as do various other loadings. I just like the Barnes TSX bullets, and was hoping for more down-range energy from that bullet. (The answer, FWIW [I posted this on another forum and got the answer almost immediately] is that the 225gr .338 TSX is not a BT bullet, like the 210gr .338 one is, for some reason). The .225gr .340 Wby in the TSX puts out the exact same energy (+1 fpe) at 400yds as does the factory .300 Win. Mag. loading in 180gr MRX (Federal), which has a much flatter trajectory. I know all the theory that bullet-placement is the ONLY thing that ever matters, but, I'm going to go on an Alaskan bear hun in the fall possibly involving long-range shots, and I will just bring the .300 Mag if I'm only getting 300 Mag energies at 400 yds. As it is, I would use the 250gr NP loads in .340. I just would like to see something better in a 225gr loading in a Barnes bullet--I personally would like to see the 225gr TTSX, but I may be in a minority. The .340 is inherently capable of hitting down range with well-over a ton of energy. I just don't want to take away that capability with a non-aerodynamic bullet.

I notice that Nosler loads the same 225gr Accubond bullet you use, and that that loading (on paper, I know) exceeds the ballistics of all of the Wby factory loads in .340 Wby at extended ranges. Do you know if that Nosler loading is good ammo? It's certainly expensive enough. Also, is the Accubond a very good option for big 3/4-ton mammals that might want to eat you? Or should I stick with the .250gr Nosler Partition or possibly even the 210gr NP?

Thanks again for the info and comments.
« Last Edit: April 06, 2009, 11:45:37 AM by MarineHawk »

James

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Re: .340 Wby Ammo
« Reply #3 on: April 06, 2009, 07:38:14 PM »
I am very confident in the 225 grain Accubond bullets and would have no hesitation about using them on elk, even at extended range. I have only killed two blacktail deer with them, both at ranges around 300 yards, give or take a few. Both deer were medium size, nothing to brag about, but the bullet performance was nothing short of stunning. Just don't put one into the "eating parts" of your game. However, one of these planted in the chest cavity of any large north-American game would be devestating. I do not believe any animal on the continent could take it, nor do I believe they will notice much difference in energy between any of the bullets you mentioned. They all deliver massive energy when fired from a .340 Weatherby.

You asked if I believe Nosler ammunition is good. I haven't fired their ammunition, so I can't give you a good answer, but I do trust that Nosler bullets and ammunition are good. I would of course work up my own charts rather than trusting published data, but I believe in the end their ammunition would be as good or better than mine.

I have to be honest here when I tell you I am uncertain whether I would choose the 225 grain Nosler Accubond, or the 250 grain Nosler partition for big bears. Both are excellent bullets. The partition would guarantee excellent penetration and I would feel very confident in its performance. The Accubond bullet would also give excellent penetration, but in addition it will provide a massive trauma and a far superior wound channel. If I planned to smash a big bear's spine or put a bullet through its heavy thick skull I suppose I'd select the partition, but the safer and more certain shot would probably be through the vitals, so I think I'd select the Accubonds.

Just keep in mind that my 225 grain Accubond is still packing just under 1200 ft/lbs of energy at 1,000 yards. That is substantially more than an average .44 magnum energy at the barrel.




« Last Edit: April 06, 2009, 07:50:46 PM by James »
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Re: .340 Wby Ammo
« Reply #4 on: May 05, 2009, 10:31:42 PM »
As I said above: "... I would really like to see Weatherby replace the 225gr TSX with a 225gr TTSX if possible ..."

WEATHERBY PEOPLE PLEASE LISTEN:

I was intrigued a couple of months ago when I saw that Cor-Bon was coming out with a new 225gr TSX loading in 340 Wby with a little more umpf than the Wby loading (3100 fps vs. 2970 fps). But it still did'nt not solve the ballistic inefficiency of the 225gr TSX round with it's low (0.386) ballistic coeficient (because it's a non-boattail). Thus, the TSX was great coming out of the muzzle of a 340, but by the time it sailed about 300 yds, it was about the same as a Nosler Partition coming out of a .338 Win. Mag. Who wants a 340 Wby that hits down range like a .338 Win Mag? Not me.

So, minutes ago, looking at the Midway and Cor-Bon website, I just learned that the new CB 225gr Barnes loading is a TTSX, not a TSX. That bullet has a great BC of 0.514. With the starting velocity/energy of 3,100 fps/4,801 ft-lbs it still delivers 3,244 ft-lbs at 300 yds and 2,467 ft-lbs at 500 yds!

Using my ballistic calculator, at long ranges, it delivers more energy, drifts less in the wind, and drops less than any round loaded by Wby (in Wby's own cartridge). And it does it with a better bullet than the Nosler Partition or Accubond. At least in that the monometal T-TSX will consistently perform better on tough game at variable ranges. In any event, it out performs all of Weatherby's loadings at all ranges in so many important characteristics. If I were a handloader, and had the time, I would load something exactly like that--a 3,100 fps 225gr TTSX.

I already sighted in my Accumark with the Wby factory 250gr NPs and was about to order more, but I just ordered five boxes of the Cor-Bon ammo and will re-sight-in for my fall Alaskan bear hunt. It's exactly what a high-end round like the 340 Wby should do--deliver 30-06 muzzle energy but at 400 yds and with a subperb premium bullet.

I would gladly order something this awesome from Weatherby if they loaded it. But, for now, I'm limited to Cor-Bon for this kind of performance. Please Weatherby, load up with some high-velocity premium bullet made for really tough game--maybe a 250gr MRX or something. Compete for my business!
« Last Edit: May 05, 2009, 10:37:07 PM by MarineHawk »

James

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Re: .340 Wby Ammo
« Reply #5 on: May 06, 2009, 03:47:57 PM »
The only detail left is to find whether that bullet at that velocity will provide the accuracy that I know you desire. I wish you the best of luck, and I hope you will post your results.
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Re: .340 Wby Ammo
« Reply #6 on: May 07, 2009, 08:01:24 PM »
Thanks Jim.  I will let you know when I get my ammo in the mail.

If I don't get good accurcay though, do you think it will be due to velocity? 

FWIW, I have already shot serveral 300 Win Mag, 340 Wby (200gr Wby load), and .223 rounds accurately that travel more than 100 fps faster than the 225gr .340 bullets I purchased, and many of the Wby factory loads in a variety of calibers are 200-400 fps faster.

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Re: .340 Wby Ammo
« Reply #7 on: May 08, 2009, 03:33:07 PM »
"If I don't get good accurcay though, do you think it will be due to velocity?"

I couldn't really say one way or the other. As everyone says, every rifle is a bit different. That is all I meant. I suppose there is some perfect speed/rotation for each bullet shot from your rifle that provides the best accuracy, so let's just hope that this bullet is that perfect match for your rifle!

This is just my opinion, but I believe a dirty barrel is the single greatest cause of poor accuracy in a rifle. Dirty lands and grooves won't provide the proper spin to your bullet, and may even deform the bullet enough to affect its flight. Without proper spin,or with damage your bullet will wobble in flight and your accuracy will be poor.
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Re: .340 Wby Ammo
« Reply #8 on: June 27, 2009, 06:40:33 PM »
MarineHawk Curious to hear how the Core Bons worked out.

Re: .340 Wby Ammo
« Reply #9 on: July 02, 2009, 08:58:02 PM »
Ridge Runner:

I just belatedly answered your PM. For the benefit of any other interest parties:

I have not fired the Cor Bon loads yet. I previously sighted in my new 340 with the 250gr Wby NP loads. I ordered six five boxes of the CorBon 225gr TTSX loads from Midway. I loved the combination of the high BC and monometal construction of the bullets in that cartridge. I got three boxes almost immediately and the other three were on backorder. I checked, and the main Midway site immediately said the rounds were on backorder (I must have gotten the only three boxes available?). I haven't shot them yet because, if I don't get at least one more box of them, I may just stick with the NP loads and leave my point of aim as is, because I want to practice/sight-in with at least two boxes and bring at least two more boxes to my September Alaskan hunt. Unfortunately, 2+2 is greater than the three boxes of CorBon ammo I have been able to get.

Sorry for my delay in responding.
« Last Edit: July 02, 2009, 08:59:33 PM by MarineHawk »

Re: .340 Wby Ammo
« Reply #10 on: July 16, 2009, 02:53:57 PM »
MarineHawk:

Getting back to your original post and the seemingly inexplicable decrease in the B.C. of the 225 of the same bullet, I am also intrigued.  Have you by any chance contacted Barnes about this?  I don't dispute that there are different methods of calculating the B.C. (with each coming up with different values), but one would think that the same manufacturer would be using the same method when performing calculations for the same bullet.  And, using the same bullet, with it's own intrinsic design, one would expect a higher B.C as the bullet got longer/heavier, while retaining it's diameter.

On the other hand, and forgive me, I am working from memory here, I believe I saw this same thing with the TTSX when I was doing some research on a different topic.  It was in either the .257, .270 or .300, since that's what I was researching.  Either way, I suspected a misprint on the B.C. but never followed up with Barnes.

Re: .340 Wby Ammo
« Reply #11 on: July 16, 2009, 09:41:37 PM »
daboyce67, One bullet was A Boat tail, the other one wasn't, is the difference in B.C.
 WBY MAG MAN

dubyam

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Re: .340 Wby Ammo
« Reply #12 on: July 16, 2009, 10:28:04 PM »
Jerry is right on - the 225 TTSX is a tipped boat-tail, while the 225 TSX is a Flat-based, untipped bullet.  Thus the difference.

On a side note, all the X-bullets were calculated differently than the TSX, and were secant ogive (more wedged or pointed) versus tangent ogive (more parabolic in tip shape), and thus the drop in BC from Barnes across the board.  As an aside, I believe a part of the drop is a larger hollow tip in the TSX versus the X, in an effort to correct the expansion issues the X was reporting at the time.  The TTSX was brought about to correct that same problem, I suspect.  The issue becomes whether or not it is wise to try to use heavily constructed bullets on thin skinned game such as deer.  Other than areas where lead core bullets are banned, the TSX, TTSX, and other such bullets are gross overkill for all but the most hyper-velocity rounds.
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Re: .340 Wby Ammo
« Reply #13 on: July 17, 2009, 08:01:46 AM »
I agree, a boat tail certainly would be expected to have a higher B.C. than a flat base and that is likely the explanation in this instance, something I should have noticed.

On the other hand, using the .270 as an example, the 130 grain has a listed B.C. of .431 and the 140 grain is listed at .404, both boat tails.  So it would seem, in that instance, that there is something else going on.  Afraid I'm gonna have to contact Barnes for clarification on this one.  Stay tuned.


Re: .340 Wby Ammo
« Reply #14 on: January 23, 2010, 09:41:37 AM »
Aren't you going to ask us to take you to our leader, marrydavidson34? Or should I call you ms. space alien?