Cast bullets in .458 Win Mag

I was waiting for someone to ask that, it took a little longer than I would have predicted.

Weatherby used the long free-bore to up his powder charges, which he could do since it lowered the initial pressure. It doesn't work when the cartridge case is already filled to powder crushing capacity.

Who feels that way? I suppose everyone who ever ran out of room in a four five eight case just about the time it was getting interesting, everyone who had compressed charges push the bullet back out of the cartridge, and most of those who have converted to the Lott.
Ok, but how does the free bore reduce velocity?
 
In the early days of the. 458 Winchester magnum following the initial advertising hype, people slowly discovered that velocity did not match published data due to unsuitable powder / case capacity issues. But now days with modern powders it is quite possible to get the advertised velocity out of these rifles.

I can match factory ammo advertised velocity with my reloads. There is still room to gain some more speed, but I don't need it. The .458 will never be a plains rifle, and at 100-150 yards the animal won't be able to tell the difference between the Lott or the Winchester version of the .458. But that's just my opinion.
 
In the early days of the. 458 Winchester magnum following the initial advertising hype, people slowly discovered that velocity did not match published data due to unsuitable powder / case capacity issues. But now days with modern powders it is quite possible to get the advertised velocity out of these rifles.

I can match factory ammo advertised velocity with my reloads. There is still room to gain some more speed, but I don't need it. The .458 will never be a plains rifle, and at 100-150 yards the animal won't be able to tell the difference between the Lott or the Winchester version of the .458. But that's just my opinion.

I beat typical factory speeds all the time, and with A2230 will take over the published reloading too. What have you shot with standard and higher velocity loadings to have a basis for comparison?
 
I beat typical factory speeds all the time, and with A2230 will take over the published reloading too. What have you shot with standard and higher velocity loadings to have a basis for comparison?

I said I don't think there is much difference in practical performance on game between 458win and Lott velocities at 150 yards and under. If you have some examples where that is not the case then it is outside my experience and I would like to hear more about it.
 
OK, I'll bite although I'll probably regret it. It might be a boring read. My experience with the .458 is mostly from zero to 200 yards. I started with loads that match factory claimed ballistics with buffalo being the main reason. At the time I didn't have all that many buffalo to my name, split between the .375 and the .416 and wasn't overly convinced that the .416 was killing anything better than the .375. I had a buffalo cull coming up when a .458 that I had ordered long before showed up out of the blue. Naturally the new gun was going to go, even if the planned conversion to .458 Lott wasn't done and since I had a favored .375 H&H that was going too. I viewed that as a perfect opportunity to decide once and for all whether it was worth while to use the big guns. Long story shortened a bit, I shot 16 buffalo on that trip and was able to conclude that the .458 did hit a lot harder, and the buffalo travelled less distance and took less shots. Still with me?

Despite being in second place the .375 did work after a fashion and since it wasn't because it was bigger or heavier it was natural to think that the only thing it had going for it was that it was faster. I got ahold of some A2230 and managed to get 450 A-Frames up to 2350 fps which is into Lott country. Things were a little slower for awhile but I shot buffalo here and there with whatever was handy. There was a borrowed .450 NE (isn't that what the .458 Win was supposed to be the replacement for?) and 30 caliber stunts before I got to try my Lottish level loads on a charging unwounded cape buffalo in Mozambique. Couldn't complain about the way those were hitting and the buffalo didn't do much more than a summersault or two. The bullets must have agreed because it was obvious that the bullets at the higher velocity were expanding quite a bit more at the new higher speed.

After that there was some lesser game leading up to more buffalo culling. It would have been a shame to not take the opportunity to learn something so a bunch of different bullets went with me, and since my favored A2230 powder wasn't going to available on the other side of the ocean that lead to having some fast loads and some with normal velocities plus 4 different softs and a couple different solids. Danged if the faster loads didn't continue to kill faster, and in the same vein the closer shots also hit harder simply because the velocity at impact was higher. I hate jumping to conclusions, so besides my own 112 buffalo on that trip I finished/recovered 20 or so that the others had hit first. Seemed like the neighbourly thing to do and I'm nothing if not neighbourly. Speaks to my upbringin'.

So anyway, where were we? Oh yeah, so after 123 buffalo with the .458 plus incidental animals to get that to say 160, plus another 20 buffalo on the good neighbour policy I'm sitting with the opinion that an A-Frame going as fast as you can push it is a force to reckoned with. The catch; 'cause there's always catch is that the Win case is filled to crimp failing capacity with the only powder that could produce those results. Add to that that the only powder that could produce those results isn't available anywhere its fun to hunt with a .458. Could it be that the .458 Lott guys were right the whole time? Just to build on that idea, there was no particular reason to stop at rod-rodded Win speeds with my new Lott chamber and the saga continues.

That's where my opinion comes from. Someone might be able to convince me otherwise, but it'll take some doing.;)
 
Interesting stuff. I guess I should pay attention to an obvious expert opinion. So you would recommend against using a 458 win for buffalo? 458 Lott would be a substantially better choice?
 
Having already done it, I sure can't say it won't work. So does the .375 for that matter. I will say that there are differences, and the differences are worthwhile. Something that you can consider, and you already know is that the .458 has come up short on factory loads for years and people have noticed the difference in performance when a couple hundred fps doesn't show up at the party. Good handloads getu it back, but pace off a hundred yards and it goes away again and you're right back where you started.

There's usually an easy way and a hard way to do something, and the Lott is the easy way. My hot .458 loads won't be found in any manual. They are compressed so heavily that they try to take themselves apart and there is no way I'd store them for any length of time confidently. The Lott has enough extra case capacity to make loading to even higher velocity levels easily and with many different powders.

I started with the idea of converting to the Lott, then resisted because it's hard to modify a rifle with so many stories hanging on it. Eventually the Lott won. Theres always an easy way and a hard way, and the Lott is the easy way. I can still use the Win Mags in it too.
 
OK, I'll bite although I'll probably regret it. It might be a boring read. My experience with the .458 is mostly from zero to 200 yards. I started with loads that match factory claimed ballistics with buffalo being the main reason. At the time I didn't have all that many buffalo to my name, split between the .375 and the .416 and wasn't overly convinced that the .416 was killing anything better than the .375. I had a buffalo cull coming up when a .458 that I had ordered long before showed up out of the blue. Naturally the new gun was going to go, even if the planned conversion to .458 Lott wasn't done and since I had a favored .375 H&H that was going too. I viewed that as a perfect opportunity to decide once and for all whether it was worth while to use the big guns. Long story shortened a bit, I shot 16 buffalo on that trip and was able to conclude that the .458 did hit a lot harder, and the buffalo travelled less distance and took less shots. Still with me?

Despite being in second place the .375 did work after a fashion and since it wasn't because it was bigger or heavier it was natural to think that the only thing it had going for it was that it was faster. I got ahold of some A2230 and managed to get 450 A-Frames up to 2350 fps which is into Lott country. Things were a little slower for awhile but I shot buffalo here and there with whatever was handy. There was a borrowed .450 NE (isn't that what the .458 Win was supposed to be the replacement for?) and 30 caliber stunts before I got to try my Lottish level loads on a charging unwounded cape buffalo in Mozambique. Couldn't complain about the way those were hitting and the buffalo didn't do much more than a summersault or two. The bullets must have agreed because it was obvious that the bullets at the higher velocity were expanding quite a bit more at the new higher speed.

After that there was some lesser game leading up to more buffalo culling. It would have been a shame to not take the opportunity to learn something so a bunch of different bullets went with me, and since my favored A2230 powder wasn't going to available on the other side of the ocean that lead to having some fast loads and some with normal velocities plus 4 different softs and a couple different solids. Danged if the faster loads didn't continue to kill faster, and in the same vein the closer shots also hit harder simply because the velocity at impact was higher. I hate jumping to conclusions, so besides my own 112 buffalo on that trip I finished/recovered 20 or so that the others had hit first. Seemed like the neighbourly thing to do and I'm nothing if not neighbourly. Speaks to my upbringin'.

So anyway, where were we? Oh yeah, so after 123 buffalo with the .458 plus incidental animals to get that to say 160, plus another 20 buffalo on the good neighbour policy I'm sitting with the opinion that an A-Frame going as fast as you can push it is a force to reckoned with. The catch; 'cause there's always catch is that the Win case is filled to crimp failing capacity with the only powder that could produce those results. Add to that that the only powder that could produce those results isn't available anywhere its fun to hunt with a .458. Could it be that the .458 Lott guys were right the whole time? Just to build on that idea, there was no particular reason to stop at rod-rodded Win speeds with my new Lott chamber and the saga continues.

That's where my opinion comes from. Someone might be able to convince me otherwise, but it'll take some doing.;)

So when does the .460 Weatherby reamer arrive, or is it a .450 Rigby? There are few client hunters with the experience you've accrued, and frankly we're fortunate to have the benefit of your observations. I suppose it follows that if big and slow is better than small and fast, then big and fast is better still, at least within the limitations of one's tolerance to recoil, combined with the structural integrity of his rifle stock.

The point of conjecture comes with the question of how light a bullet is prudent for use on heavy dangerous game if velocity is viewed as the primary consideration. Where is the tipping point where failures begin to occur because penetration suffers due to a lack of bullet mass, despite a high impact velocity? Is it prudent to use a .458/350 expanding bullet because you can achieve impact velocities approaching 3000 fps from a large capacity cartridge, or does a light weight solid with an impact velocity in excess of 3000 fps outperform a heavier expanding bullet impacting 500 fps slower? At one time an impact velocity of 2400 fps was deemed optimal, given the bullet technology of the day, and in the case of a large capacity .458 cartridge, those ballistics are available with bullets having sufficient SD to meet the toughest challenges. If higher velocities are deemed desirable, it comes at the cost of bullet weight. The question is, does it matter?
 
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Its hard to draw sweeping conclusions, partly because velocity and bullet construction are so closely intertwined. I can comment on at least one 350 expanding bullet though. I loaded up a pile of 350 grain TSXs for the dual purpose of testing and a little recoil refuge if needed. My velocities with those were in the 2600 plus range and they did a good job of killing buffalo, and penetration always seemed to be to the hide on the far side so how does more penetration benefit. They didn't quite have the hitting power of the A-Frames and CEBs at close range, but how much of that was due to the lighter weight and how much due to the difference in bullet construction? Its a hard thing to know without devising a test with two bullets of identical construction but different weights, then shooting enough animals to get a definite pattern. I can get 2800 out of those bullets in the Lott, and maybe someday will get to see what damage they can do. I do know that the TSXs expanded less as range increased, and if nothing else a higher velocity would take the same results a little farther down the road. Nothing in my life so far has suggested that going faster doesn't work better, just as long as penetration and bullet construction requirements are met. Which brings us full circle back to velocity and bullet construction being impossible to separate.

My biggest regret of the test was I wasn't able to use the 380 grain Rhinos you gave me. There was a problem with the camp .375. Hopefully there will be another chance or I may be able to find a volunteer to do it for me/us.

450 Rigby would be fun, my .416 isn't doing anything these days.
 
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