What would be involved in rechambering my 458WM for 458 Lott?

Cost?

Pros?

Cons?

Who / where could I have it done?

The rifle is a Remington KS Safari.

Thanks for the help.

Mine cost about $300

Pro was that I had a Lott

Con is that I really didnt need it - the 458 wm does everything I need it to in a bolt rifle.

If hunting elephant I would want a double rifle and I don't plan to kill another elephant anyway.

Who - I used Roger Biesen but don't know if he works on Remingtons.

Is that a push feed Remington that you have?

Push feed? Yes.

Assuming the magazine box is long enough, you are probably looking at $250-$400.

Pros, you get an extra 200 fps on those 500 gr bullets.

Cons, harder on the shoulder, harder on the wallet, a little harder to find ammo.

John

I had an old Remington Model 700 action that had been re-barreled to a .458 WM, & wanted it re-chambered to .458 Lott. All that was required was to ream out the chamber to .458 Lott, which was done by the guys at Douglas Barrels close to where I live, at a very low cost, & it feeds fine and shoots great. I'm a little confused as to why it should cost a few hundred dollars.

I did a Winchester, an Interarms and a Remington. I had Lex at Barnes Bullets do them all in 1991, I heard he is not there anymore. I paid $100 to ream and modify the magazine on the Winchester, $80 on the Interarms and Remington for reaming only as lengthening the box was another $200+ each and the rifles was never going anywhere other than the range. The Winchester was/is my deer rifle.

The advantage was about 120fps in the Winchester with 500gr Hornadys which I am sure really helps me bag my deer

Matthew

Waste of your money.

For 500 grain bullets just load the .458WM to 2200, or 450 flat point solids to 2250. Easy to do and no point in loading faster. For deer or whatever load the 350TSX to 2600 or 2700.

I had my Remington 700 KS LH Safari (Left Handed) re-chambered from 458 Win to 458 Lott.
All it took was a rental chamber reamer.
The action and magazine are long enough so no changes with the box. The feed is good.
The reason for my re-chamber was very poor accuracy from the start with this rifle.
The rifle had a very long throat.
As the rifle came from the Remington Custom Shop in 458, you could drop a Hornady 500 grain FMJ into the open action and then insert a dummy 458 case loaded with a 350 grain Spear bullet (but no powder or primer)and then close the bolt with no contact between the chambered dummy round and the loose 500 grain bullet.
I wrote a letter to Remington about this “excessively long throat” and I received no reply.
Now by using the 458 Lott case the bullet is seated out forward by 0.3 inch, and the accuracy is improved.
But there is a noticeable increase in recoil.
If I was to do it all over, I would buy a Ruger 77 LH with a magnum boltface and just have it rebarreled to 458 Win by one of the better barrel makers.

For some reason a lot of .458WMs have a lot of freebore.

If your magazine will take longer-than-normal (3.44") rounds, and you shoot banded bullets like Barnes or North Fork, you can just basically load the bullets out farther and get more case capacity with the same crimp in a different groove. The result is higher velocity without higher pressure and little, if any, advantage to the Lott without rechambering.

Thanks for the guidance. For what it's worth, let me say that this rifle is only to be used for three things:

1. Buffalo
2. Elephant
3. Animals encountered on the trail of 1 and 2, above.

Shooting big uglies with 500 grain bullets is this rifle's only mission in life.

Indy, given what I'm shooting at, and given that I shoot off the shelf ammo (I'm not a reloader) do you think this is still a waste of money to rechamber to a lott.

Virginia Creeper, my rifle is the KS Custom as well. Funny that I have great accuracy out of the rifle out to 100 yards. I rather like it and have the same rifle in 375. Sorry that your experience was not as good as mine.

Finally, even with the lott convert I can still shoot 458WM ammo, right?

quote:

Originally posted by Indy:
For some reason a lot of .458WMs have a lot of freebore.

If your magazine will take longer-than-normal (3.44") rounds, and you shoot banded bullets like Barnes or North Fork, you can just basically load the bullets out farther and get more case capacity with the same crimp in a different groove. The result is higher velocity without higher pressure and little, if any, advantage to the Lott without rechambering.

Not sure of the factories reasoning for doing so, but often freebore is introduced to manage pressures. I would agree with those that say if you have a perfectly good shooting 458 win, leave it as is, if you do have problems, or are buying new, to a look at the lott.

The recoil is about 70%-80% more than the 458 win, for just another 100-200 fps more. But it is easier to load it down than to load up the 458 win.

With Hornady's heavy magnum ammo, you will have a bang up combo for Elephant and Buffalo, without handloading.

With the lott, you can shoot 458 win mag through it when needed, but you do get velocity fall off, and some reduced accuracy, and will likely need to re-sight the rifle.

John

quote:

Originally posted by safari-lawyer:
Thanks for the guidance. For what it's worth, let me say that this rifle is only to be used for three things:

1. Buffalo
2. Elephant
3. Animals encountered on the trail of 1 and 2, above.

Shooting big uglies with 500 grain bullets is this rifle's only mission in life.

Indy, given what I'm shooting at, and given that I shoot off the shelf ammo (I'm not a reloader) do you think this is still a waste of money to rechamber to a lott.

Virginia Creeper, my rifle is the KS Custom as well. Funny that I have great accuracy out of the rifle out to 100 yards. I rather like it and have the same rifle in 375. Sorry that your experience was not as good as mine.

Finally, even with the lott convert I can still shoot 458WM ammo, right?

If you can goose 458 WM's to 2200 fps then you can get so much more from a Lott too!

When I converted a 458 WM to s Lott before you could buy a CZ 550 in a Lott, I just bought a reamer and did it myself. If you get/rent one w/o a cutter for the belt you just run it into the chamber until it stops. Mine took some tweaking on the rails and ramp to get it to feed fast and slow.

I was lucky and it worked fine but of course if you screw it up too bad it could have a new career as a boat anchor.

Can always shoot 458 WM in a Lott but not vice versa. Might as well make a Lott out of it.

Should be be pretty cheap to get someone to do it nowadays.

Reply to the Safari Lawyer:
The magazine length of the Remington 700 factory made rifles in 458 Winchester Magnum is all full 3.6 inches. That is long enough for the 375 H&H or the 458 Lott without any problems.
If your 458 WM, factory made on a Remington 700 KS, now shoots accurately, why change anything to go to a Lott.
There is a difference in a Client’s Rifle from a PH’s Rifle.
A light weight and accurate 458 Winchester Magnum is an ideal Client Rifle. (All 458 WM ammos problems are historic.)
A light weight and accurate 458 Lott is an ideal PH’s Rifle.
And you are the...(pick one of the above)?
Sincerely,

quote:

Originally posted by safari-lawyer:
Thanks for the guidance. For what it's worth, let me say that this rifle is only to be used for three things:

1. Buffalo
2. Elephant
3. Animals encountered on the trail of 1 and 2, above.

Shooting big uglies with 500 grain bullets is this rifle's only mission in life.

Indy, given what I'm shooting at, and given that I shoot off the shelf ammo (I'm not a reloader) do you think this is still a waste of money to rechamber to a lott.

Virginia Creeper, my rifle is the KS Custom as well. Funny that I have great accuracy out of the rifle out to 100 yards. I rather like it and have the same rifle in 375. Sorry that your experience was not as good as mine.

Finally, even with the lott convert I can still shoot 458WM ammo, right?

If I couldn't shoot handloads, and I didn't already have a .458 WM, I would favor the .458 Lott. I'm a handloader and I don't believe I have ever killed a game animal with a factory round. I really like the 450 grain North Forks. There's evidence that they out penetrate, in solids, 500 grain Woodleighs. Recoil is less even with WM velocities. But you can't gete them in factory ammo.

You could always get Superior Ammo or someone to handload for you, though.

Pro's for the Lott: if you really need to spend some money, a 458 Lott is what you've always dreamed of having or your just bored with the 458wm.

Con's for the Lott: with the new powders for the 458wm it can get a 500 grain bullet to 2150fps out of a 22inch barrel with the same chamber pressures of the Lott doing 2250fps. IMO, no net gain with the costs involved.

I agree with most here that the .458 WM is enough gun, especially if you reload. But if you want to turn it into a Lott, I would be happy to do it for $75 plus shipping if the mag doesn't need extending. Your mag length should be 3.600" or greater. The Lott max C.O.L. is 3.600" for factory ammo. A-square ammo is 3.550". Your mag shouldn't need to be extended.......Tom

Well, there you go. Cheaper than dirt.

I did what Will did for the same reason. Did it by hand,slowly, and it worked fine.
Tom sounds like the answer.
Larry

quote:

Originally posted by Will

If you can goose 458 WM's to 2200 fps then you can get so much more from a Lott too!

I think what Indy was getting at is that if the magazine is already long enough to handle the Lott, then with Barnes Banded, TSX's or North Forks the bullets can be seated out to match the Lott anyway by simply crimping in one of the bottom grooves. There is plenty of "freebore", or leade, in the .458WM to allow that. That's what I do in my CZ550 (.458WM). Therefore there's no advantage to the Lott in such a scenario, because by doing the above you have as much room for powder as the Lott when loaded to a COL of 3.6". Actually, in my CZ, I can load the long monos to 3.75" if wanted, and still have freebore, which you can't do in a magazine that barely allows for a COL of 3.6". Even in a CZ550 Lott, it's true you could seat the bullet to 3.75" (PERHAPS NOT!- because the length of the .458WM chamber, including leade is about .17" longer than the Lott to begin with!). But that's possible ONLY in a CZ, or similar true magnum-length actions, NOT in the M700!

Bob

www.bigbores.ca

And regarding recoil:

If we take Hornady's data for both rifles, using their best loads, and giving equal weight to the rifles, the difference in recoil is 9.5%.

I mention this because I've seen figures on AR going anywhere from 40% to 80%!!!

Bob

www.bigbores.ca

Ok, now I have a question: My 458wm is a pre64 and if the freebore and magazine will allow, why can't I seat the bullet further out decreasing the chamber pressure and allowing more accuracy from the 458wm; or, am I misreading the above posts?

if it fits, there's nothing to it..

whatever you can do with a winmag (gent's that 3.34") you can do better with a lott.

at 3.65, it doesn't matter which case, its the same capacity.

some folks tend to mislead as to what and how they are loading the "winmag"

Yes, you can load a .458 win Mag out about .25 inches assuming the mag has enough room. You'll need to put a new cannalure on the bullet( Corbin sells the tool). you can use a drop tube to get more powder in the case and it works extremely well. With that said its incredibly easy to convert most .458win mags to the Lott and if you dont reload thats the best option.-Rob

Remington has long action and magazine box. Rechambering is a natural. Minimum cost. Major flexibility gains. No cons. Any competant smith.

Will,

I've been a M700 fan for many years and I like the 458WM a whole bunch. Like many have said the conversion from 458WM to Lott is a simple matter wit hyour rifle and probably will require zero tweeking but I have to agree with the other poster that essentially said "If it aint broke.....". My suggestion might be since you are not a handloader to have Superior Ammunition 1-800-677-8737 load some 450gr TSX's and Barnes Banded Solids. Out of a 24" barrel you'll get 2300 FPS. With these loads you will be set for about anything you'll encounter on the ele or buff trail.

Mark

I own one 458 Lott and if you hold it tight into your shoulder it doesn't hurt. You can ajust your hold after that first shot.

quote:

Originally posted by Robgunbuilder:
Yes, you can load a .458 win Mag out about .25 inches assuming the mag has enough room. You'll need to put a new cannalure on the bullet( Corbin sells the tool). you can use a drop tube to get more powder in the case and it works extremely well. With that said its incredibly easy to convert most .458win mags to the Lott and if you dont reload thats the best option.-Rob

Hi Rob;

You have incredible knowledge of rifles and building them. And I sincerely give you due respect.

Having said that please hear me out: I'm not trying to be smart or argumentative because I've written and published a manual on the .458 Win Mag, and I can't afford to be wrong about this.

My .458WM is in a CZ 550 with the full length 550 action and magazine. In other words, I can, and have, chambered rounds, using the 450gr Barnes X (same length as the TSX) from 3.63" to 3.8" into the chamber of my rifle and closed the bolt. 3.83" is touching the lands(no freebore), 3.63" has .20" "freebore" or "jump" to the lands. As you know, the current Barnes TSX's and solids have "bands" or grooves. If I crimp into the second from bottom groove of the 450gr TSX, I have a COL of 3.6" with .413" into the case.

Using the same procedure, I can load the 500gr TSX to 3.6" and crimp into the second groove with .559" into the case, exactly the same as the 458 Lott, with this difference only: for the Lott you must crimp into the top groove for a COL of 3.6" and .859" into the case. .859 minus .559 = .30, the difference between the two case lengths... meaning the Lott has nil advantage using that example.

In my former post, I made reference to Barnes' TSX's and Banded Solids, as well as North Forks, in which it is possible to seat bullets as long as the Lott and still have enough bullet into the case while using a crimp at the same time.

Here are some figures from Barnes showing that at least in their test barrels the .458 Winchester has a .129" advantage over the Lott when loading the 500gr Banded Solid in each:

In the .458WM with a COL of 3.310" it was .717" off the lands!

In the .458 Lott with a COL of 3.580", it was .288" off the lands!

.717 minus .288 = .429" The difference in case length as we all know is .30". Therefore the .458WM still has .129" more leade, or freebore.

That goes along with schematics I've seen, as well as in discussions with my gunsmith, who is a world class smith, and people at Hornady who finally came up with some numbers. Also, the late Finn Aagaard, in testing a number of .458WM's, gave the numbers for the freebore in each with a 500-grain Hornady RN seated. They were all over .710" except for his custom job.

What does it all mean? Well, it's fairly obvious to anyone with a modicum of math skills, that the .458 Win Mag has more "room" or volume in it's total chamber than the Lott. Therefore anyone with an action that allows a COL of 3.6" or more in the .458WM, and being a handloader, need only seat the bullets out to equal the Lott. If they're not a handloader, go with the Lott if they feel they need more than what they can get from Superior, Winchester or Hornady.

Again, with all due respect,

Bob

www.bigbores.ca

quote:

Originally posted by .458 Only:
..I've written and published a manual on the .458 Win Mag, and I can't afford to be wrong about this.

this explains everything, mostly your agenda

quote:

Originally posted by .458 Only:

My .458WM ..{loaded to}.3.63" to 3.8" into the chamber of my rifle and closed the bolt.

No, sir. SAAMI, here, page 89, as marked on the pages, , defines a 458 winmag CARTRIDGE as 3.34" long, http://www.saami.org/Publications/206.pdf goto page 89 .

the chamber, of course, is longer.

Your post explains every arguement you have made "Defending" the winmag as being the equal of the lott. You are loading a winmag case, at the length of a lott round. Of course you are having superior results.

Thank you for reinforcing the improvement of the lott over the winmag, as your own writing decry that the .458, loaded to 3.65 more or less, if far superior to one loaded at 3.34, the spec for the 458 winmag.

Of course you won't agree, but that's not relevent.

One simple reason to have the Lott intstead of the 458 is because you can't stick the Lott into a 458.

I see them as being similar to 375 H&H and 375 Wby/AckImp but with one difference. In the case of a real top end custom gun that is Mauser or M70 based there is a lot more value having 375 H&H engraved on the rifle than the 375 Wby. Not so for the 458 Winchester and in fact I suspect the 458 Lott would be a more desirable name than the 458 Winchester.

quote:

No, sir. SAAMI, here, page 89, as marked on the pages, , defines a 458 winmag CARTRIDGE as 3.34" long

So, applying the same logic, if the Lott is shortened or lengthened beyond 3.6", it's no longer a Lott?

Or, should someone load a 45-70 to 40,000 psi it's no longer a 45-70 due to the fact that SAAMI says it's maximum CUP is 28,000?

Or should someone load a Ruger No.1 in 45-70 with a 500gr Hornady to a COL of 2.93", it's no longer a 45-70? Especially if it's loaded to 50,000 CUP?

And should a 300 Win Mag be loaded to 3160 fps with a 180 NP, that disqualifies it from now to forever from being a 300WM because someone (like Nosler)is trying to mimic 300 Weatherby velocities?

Bob

www.bigbores.ca

3.6 or whatever does not comply with the standard 458. In the case of rifles lile the CZ or Wby Mark V etc you have allowed the rifle to determine the cartridge and its ballistics. But it is not true specification because a bloke with a Model 70 can't use that ammo as a repeater.

But let's say the shooter has a CZ or Mark V in 458 (picked those two because they would be the most likely with a longer than 3.6" magazine) then 458 Lott brass or ammo is of no use to him. But he rechambers to 458 Lott then he can use 458 Lott and 458 Winchester.

The only sense the 458 Winchester makes is in some rifle like the M70 African or Post 64 Supergrades where there is collector status.

Interesting thread, but I get the feeling apples and oranges are being discussed. In their SAAMI-spec, factory configuration, the Lott has more oomph--a technical term--than the Win Mag. Handloaded, all bets are off, as they are whenever one deviates from factory loadings. The Win Mag can be loaded to Lott performance levels, the Lott can be used to plink prairie dogs, etc.

To me, more case capacity equals, ultimately more performance. Angels dancing on the head of a pin.

Dave Manson

quote:

Originally posted by DManson:
Interesting thread, but I get the feeling apples and oranges are being discussed. In their SAAMI-spec, factory configuration, the Lott has more oomph--a technical term--than the Win Mag. Handloaded, all bets are off, as they are whenever one deviates from factory loadings. The Win Mag can be loaded to Lott performance levels, the Lott can be used to plink prairie dogs, etc.

To me, more case capacity equals, ultimately more performance. Angels dancing on the head of a pin.

Dave Manson

Yeah, bigger case, bigger humper. Go figger!!

Let me start by saying that NO ONE questions your results in loading the 458 winmag to utilize the cz550 magizine length. No one. Your results speak for themself .. if one seats a winmag out very long, one can achieve greater results than otherwise normally seen.

quote:

Originally posted by .458 Only:

quote:

No, sir. SAAMI, here, page 89, as marked on the pages, , defines a 458 winmag CARTRIDGE as 3.34" long

So, applying the same logic, if the Lott is shortened or lengthened beyond 3.6", it's no longer a Lott?

Then we agree that SAAMI is a respected source for deteremining what is and isn't a spec round? By using your same logic, one would have to load the load to .3 to .5 longer than 3.65, not 3.6, spec. Shorter has nothing to do with the conversationand MAX oal is a length limiter in the + direction

quote:

Originally posted by .458 Only

Or, should someone load a 45-70 to 40,000 psi it's no longer a 45-70 due to the fact that SAAMI says it's maximum CUP is 28,000?

purposely overloaded rounds are no longer spec, yes. However, when stated "marlin only" then one knows that those are NOT spec 45/70 loads. Ammo makers CLEARLY mark their ammo when its purposely over pressure. Cases say +P, or boxes say "for modern actions only" In your loading case, if you said "458 winmag, loaded to lott length" you would have an honest comparison.

quote:

Originally posted by .458 Only

Or should someone load a Ruger No.1 in 45-70 with a 500gr Hornady to a COL of 2.93", it's no longer a 45-70? Especially if it's loaded to 50,000 CUP?

sir, we are talking about your loading of the winmag, not hot rodding the 45/70. Though, yes, loading a 45/70 with RUGER or BOLT ACTION ONLY loads no longer makes is a saami or cip 45/70 - no more than 257+P or 9MM+p+ or 38 spec +p are spec loads.

quote:

Originally posted by .458 Only

And should a 300 Win Mag be loaded to 3160 fps with a 180 NP, that disqualifies it from now to forever from being a 300WM because someone (like Nosler)is trying to mimic 300 Weatherby velocities?

ah, now you are stepping into a THIRD arguementative technique of again, a disgtractor. but you make my point, which i'll share in a moment. Thank you for making these perfectly clear to discuss

quote:

Originally posted by .458 Only
Bob

www.bigbores.ca

Bob,
(your combined second point first) a 45/70 at 50K cup (or 40K psi ... these are GROSSLY different pressures, you know that right? PSI and cup are only nearly the same at 28k) in a specific ruger/bolt gun ONLY loading is no longer a saamo 45/70, and the ammo makers are quick and clear to mark the boxes and/or ammo as such. It, at least, damage a good deal of all the guns its designed for.

This raises a CRITICAL issue, that of safety ... a 500gr ruger only load would get someone killed in a trapdoor. This is not safe. I don't know about you, but i am a safety first kinda guy.

Your third point - otherwise spec ammo that goes faster, a al Nosler and hornady light/heavy mags. If SAAMI calls for max 3.34" oal and 62.4K PSI/55K CUP, and these rounds are loaded within those ranges, then the only difference is powder .. One can get 62.4k psi with bluedot and with rl22 ... which one is going to go faster in that 300 win? the rel22, of course. Everyone knows that powder choice makes all the difference, within the same pressure, for performance.

First point last - is a lott loaded to shorter still spec? Sir, that's NOT your position. Your position is that a 458 winmag can (near) equal a lott. The caveats being that first you must load it as along as a lott, and second that it must fit into your rifle.

which, of course, are all obviated if one used a lott case in the first place.

Bob, you have affirmed, at least to some of us, that the correct length for a high performance HH case based .458 DGR is between 3.6 and 3.8 inches OAL. The shortest factory route to that solution is... the 458 Lott .

quote:

Originally posted by Will:

quote:

Originally posted by DManson:
Interesting thread, but I get the feeling apples and oranges are being discussed. In their SAAMI-spec, factory configuration, the Lott has more oomph--a technical term--than the Win Mag. Handloaded, all bets are off, as they are whenever one deviates from factory loadings. The Win Mag can be loaded to Lott performance levels, the Lott can be used to plink prairie dogs, etc.

To me, more case capacity equals, ultimately more performance. Angels dancing on the head of a pin.

Dave Manson

Yeah, bigger case, bigger humper. Go figger!!

Thanks Dave and Will ..

and Bob even actually agrees, which is why he loads the winmag to lott length!

quote:

and Bob even actually agrees, which is why he loads the winmag to lott length!

Thanks Jeffe... and have a nice day.

My point has NEVER been to show (or prove) that the .458WM based on SAAMI is equal to or better than a .458 Lott based on SAAMI. If someone is trying to imply that I've said or implied that, then they have not read my various comments on AR, and elsewhere, or they have not paid attention to what I've said, or they have their own agenda.

What I have written here, and elsewhere, including my manual is this:

1) In the CZ (and the BRNO 602) it IS possible to load it like a Lott if needed or wanted; and,

2) I doubt that it's NEEDED because with todays powders one can achieve 2200 fps anyway, within SAAMI specs in a 24" tube. I'll not argue this last point because I feel, from evidence, that it has been well established (Hornady 7th Edition and Accurate Arms Web site, as examples, though not the only).

Indy has gone on record several times clearly stating he can, and has gotten 2200 fps from BOTH 500gr softs and solids using AA2230. Phil Shoemaker has made a similar claim. And I know what I can get from my 22" Ruger No.1 in 45-70 (long throated), which was tested for me. JPK has gone on record in declaring his double is capable of 2145 fps using 500 softs and solids with pressure well below SAAMI. He keeps it there for regulation purposes. And,

3) I have stated here, and elsewhere, that I believe the difference between the two cartridges, keeping everything equal (ideal, but not realistic as there are too many variables)that the real difference is 100 fps (max)in favor of the Lott, employing 500-grainers. No doubt there are those who will argue that point but Shoemaker's article on the Lott provides strong evidence for that point of view, as well as Hornady's manual and my own experience.

So, I'm happy to leave it there and will no longer discuss it here.

I'm certain, based on evidence, that the "right" 500-grain at 2200 fps or 2300 fps will get the job done on anything with fir, horns, sharp teeth, thick skin, hooves or claws, providing the bullet gets to the right place!

I failed to mention birds, reptiles and fish, but I'm sure it would even work for those as well in good hands!

Best regards to all!

Bob

www.bigbores.ca

Thanks to all of you for the many comments and advice on this topic.