.458 Lott to .450 Ackley magnum conversion?

Jarrah

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Anyone have experience with this round or conversion?

I have a Ruger no.1 in .458 Lott and read that it can be 'improved' by having a gunsmith straighten the chamber to create a small shoulder and slightly increase powder capacity.

Apparently velocity gain is somewhat nominal (50-100fps) and as far as I know factory ammo isn't available for this calibre but I handload so ammo isn't so much of a problem. Ultimately velocity increase is still velocity increase.

I should add that I predominantly use this rifle domestically with most satisfactory results in scrub at close range for feral animals and small vermin using light frangible rounds loaded as fast as I can reasonably get them.
 
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The 458 Lott is already an Improved 458WM.....

My question is...What can you do with a 450 Ackley that you can't do with a 458 Lott + / - 50 fps???

That said, all it takes is a competent gunsmith with the proper reamer...

Some brass, components, and range time and you will have a real big bore wildcat!!!
 
I would rather go with the 458 express 3" length case vs 2.8" all you have to do is ream out the chamber a tad longer.

Less fuss and more space for more powder.
 
Before you do anything have a gunsmith measure your chamber and then measure your mag also. The mag may be limited to 3.8 in. and it’s possible your chamber may exceed Lott dimensions. Go from there.
 
Before you do anything have a gunsmith measure your chamber and then measure your mag also. The mag may be limited to 3.8 in. and it’s possible your chamber may exceed Lott dimensions. Go from there.

Errrr it's a ruger no1 he is talking about converting...... :E Big Grin:
 
“I should add that I predominantly use this rifle domestically with most satisfactory results in scrub at close range for feral animals and small vermin using light frangible rounds “

You have a rifle that gives you “most satisfactory” results for your use case and you want to change it?!

If it ain’t broke, fix it until it is…
 
I should add that I predominantly use this rifle domestically with most satisfactory results in scrub at close range for feral animals and small vermin using light frangible rounds loaded as fast as I can reasonably get them.
Gains for DG loads would be minimal, and no real world as applied distinction. I have no idea what feral animals you are shooting, but small vermin certainly will not detect the difference. Not worth the investment for me, but have at it if you want.
 
JD Jones.... 50x3 1/4 Sharps 750. It's a beast, and he can build it on a No. 1 :)
Funny you posted this as I'm thinking the same thing. My No1 is a 50-90 so really an easy conversion to a 50-140. I think (read "I don't know") that I can still shoot 50-90's out of the thing without damaging the barrel.

There's really no reason to do this other that the whole mine is bigger than yours thing.
 
Funny you posted this as I'm thinking the same thing. My No1 is a 50-90 so really an easy conversion to a 50-140. I think (read "I don't know") that I can still shoot 50-90's out of the thing without damaging the barrel.

There's really no reason to do this other that the whole mine is bigger than yours thing.
My No. 1 is a .45-70. It's got a shorter throat than my Marlin 1895 Cowboy .45-70. It also goes off about 1/3 the time when you close the lever (the Ruger does), so I really need to get it fixed. Haven't shot it in probably 20 years. I'd like to do something with it. Thought about rebarreling to a .450 Nitro or at least a longer barrel (for some reason Ruger put a really short barrel on the .45-70 No. 1) and doing a .45-120 that I could do black powder or smokeless and basically have a .450 Nitro. My understanding is that the Nitro Express cartridges are larger in diameter than the old "Sharps" cartridges and it can mean reaming out the receiver too much on the Ruger. The old Sharps cartridges are skinnier, and length doesn't really matter. Maybe a .450 #2 :) I think they're about 4" long overall....ha ha. A .45-90 smokeless would do about all you'd need to do. A .45-120 smokeless, I think, would drop about anything. But I'm building a .458 Lott/.450 Watts Enfield A-Square Hannibal clone right now. So that will be my "Big and Ugly" gun. I need to quit building guns and get my tail over to Africa! :)
 
As John Wayne said in Hondo, “a Man oughta do what he thinks is best.” Here’s my opinion.

Converting your Ruger #1 from 458 Lott to 450 Ackley may be possible, but I can’t think of a single reason to do so.
 
My No. 1 is a .45-70. It's got a shorter throat than my Marlin 1895 Cowboy .45-70. It also goes off about 1/3 the time when you close the lever (the Ruger does), so I really need to get it fixed. Haven't shot it in probably 20 years. I'd like to do something with it. Thought about rebarreling to a .450 Nitro or at least a longer barrel (for some reason Ruger put a really short barrel on the .45-70 No. 1) and doing a .45-120 that I could do black powder or smokeless and basically have a .450 Nitro. My understanding is that the Nitro Express cartridges are larger in diameter than the old "Sharps" cartridges and it can mean reaming out the receiver too much on the Ruger. The old Sharps cartridges are skinnier, and length doesn't really matter. Maybe a .450 #2 :) I think they're about 4" long overall....ha ha. A .45-90 smokeless would do about all you'd need to do. A .45-120 smokeless, I think, would drop about anything. But I'm building a .458 Lott/.450 Watts Enfield A-Square Hannibal clone right now. So that will be my "Big and Ugly" gun. I need to quit building guns and get my tail over to Africa! :)
I have a no3 that loves 500gr Hard cast, I'm making it I to a no1 1/2, so it fits me better. That thing has no lop for me.
 
“I should add that I predominantly use this rifle domestically with most satisfactory results in scrub at close range for feral animals and small vermin using light frangible rounds “

You have a rifle that gives you “most satisfactory” results for your use case and you want to change it?!

If it ain’t broke, fix it until it is…
This is a hobby not a job. Changing and modifying guns is part of the fun, at least to me
 
My understanding is that the Nitro Express cartridges are larger in diameter than the old "Sharps" cartridges and it can mean reaming out the receiver too much on the Ruger. The old Sharps cartridges are skinnier, and length
The difference in case body geometry of a 50-90 Sharps and a 500 NE, other than length, is negligible however the rim is quite different, the Sharps being more robust .... but that is not the focus of this thread and I apologize for that.

I happen to have a 45-90 Rolling Block. That is that longest 45cal I could fit in that rifle because of the large hammer inline with the chamber; obviously the Ruger No 1 doesn't have that problem. On my first bison hunt I mistakenly handloaded it to 458WM equivalent and shot through the bison 4-times before it realized it was dead. On my next bison hunt I loaded it with a black powder substitute tipped with a 500gr paper patch bullet with much, much better results.

That is certainly a serious issue with your No 1, never heard of that before. I'm a bit surprised that you haven't had that addressed in 20-years.

Back to 458 Lott' 450 Ackley thing. I personally don't see the point of doing it but each to their own. By Jarrah's own admission he's just aren't gaining that much.
 
Sometimes being different doesn't gain you a lot in fps, but it sure is neat to do. Most of us gun cranks have done this. Like building a 308 Norma instead of 300 win or a 35 brown instead of a 35 Whelen. About the same, but enough for someone to say " it's a what????". I say do it and have fun with it. I personally have several Ackley's, some are better then others, but in the end, it's all in what turns your crank. On another note, I wonder if the Ackley will give you less high pressure spikes at or near max loads in the heat of Africa?
 

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