New Life for an Older 458 B&M..............

[Tanks]

Lol! I guess I'll have to start looking for a used short mag Winchester model 70 action!

If you are serious about it @michael458 might have some to spare unless people have finished it all. He was scouring the internet for WSM actions a while back to help out people that needed them. I got one lefty action from him, another from a Gunbroker lefty .270 WSM donor.

 

[rosenberger stephen]

Have read about the B&M story, don't understand why it works or the mechanics behind it.

 

[hoytcanon]

Just stick with a .458 Win Mag. Good to go.

 

[Grumpy gumpy]

Just stick with a .458 Win Mag. Good to go.

You may have opened a can of worms with that one……..
Gumpy

 

[TOBY458]

You may have opened a can of worms with that one……..
Gumpy

The 458 long throaters and Lottites will be along soon. LOL!

 

[Altitude sickness]

Instead of carrying multiple scopes. For one rifle with different loads. It’s much easier and cheaper to have custom turrets made for the additional load.

You need a scope that tracks reliably so you can return to zero for each custom turret.

That would seem to be the best of both worlds for sure. If you can get both of those loads to print that closely, it would be the answer to most any questions you might run across. I suppose if your rifle didn't group the different loads that closely, the next best thing would be a different scope for each load in QD mounts. I don't like adjusting scopes in the field, so I would prefer to swap the scope with the load.

 

[John J]

Just stick with a .458 Win Mag. Good to go.

Yes, but not as cool

 

[hoytcanon]

View attachment 651030
Yes, but not as cool

Disagree...

You may have opened a can of worms with that one……..
Gumpy

Yeah, I know... but winter is coming on, three months before I hunt again, might as well poke a sleeping bear, and see what sort of fun ensues.

 

[hoytcanon]

View attachment 651030
Yes, but not as cool

Disagree... history makes something "cool." There is a difference between "interesting" and "cool." I have a little of both and don't begrudge anyone their little indulgences.

 

[RLL]

What’s not to love about the B&M line?

 

[John J]

Disagree... history makes something "cool." There is a difference between "interesting" and "cool." I have a little of both and don't begrudge anyone their little indulgences.

Yes, it was a wise ass remark.

 

[AZDAVE]

Well after I purchased my 458 B&M I sold my 458 WM. Totally redundant in that power level. In addition was able to find ultra MAG cases much easier than WM cases.

To each his own. Both are good rounds.

 

[michael458]

Just stick with a .458 Win Mag. Good to go.

Well, if one can ONLY choose ONE Rifle/Cartridge, then I would not really disagree with that statement, you can come out very well with a good ole 458 Winchester and never need for more, or even less....... Did not expect that eh?................. Well, let me tell you a little story............

I did not come up with the B&M Cartridges by trying to improve on any existing cartridges! My goal was not "Cartridge" Oriented. I did not set out to make a bigger, better, faster .458 caliber cartridge, that had little or nothing to do with it.

It had everything to do with the "Platform" that the Cartridge is based upon!

I late 2005 all the stars, Sun and Moon were in alignment............

October 2005 found me and my lovely Wife in Tanzania. I was after Buffalo mostly and then whatever else came within sights........... I was carrying a Winchester M70 458 Lott African Edition #50. They only made 50 of these, I had #50 and #13 of the series. This 458 Lott still had a Musket barrel of 24 inches, came in with scope probably around 10-10.5 lbs. For my small caliber gun I had a Winchester M70 416 Remington, was mostly shooting the 340 Woodleighs that year, I would have to look at the exact load and velocity, but it proved to do a decent job on zebra and such, one and only leopard I had ever taken and a charging Roan. I liked the bullet, so good that for a conventional bullet I used my leftovers not so long ago for shelf ammo for my own 416 B&Ms........

Now, back to a real rifle and cartridge, 458 Lott........... That year I was using a combination 500 Swift A Frame and 500 Barnes FN Solids........ Proved to be an excellent combination on several buffalo, and I was astounded at just how hard the 500 Barnes Solids hit up front, a vast difference from the old RN versions........ You could see buffalo react to taking that FN Solid.......

We got involved in an Altercation between two bull hippos one day. We just happened to be there in the right/wrong place to witness the after effects. The looser of the ordeal was not very happy, and spotted us up above him and here he came. Now the bank we were standing on was too steep for him to come direct, so in a round about way he made his way up to us. This seemed to take a long time in my mind. Now I was ready, up in arms you might say, with a very very very LONG Musket size gun, that now felt like it weighed in at 25 ++++ Lbs, I was getting weak in the arms holding this thing, this fat, long, overweight 458 Lott! In this time I was thinking to myself "God there has to be something better than this to fight the beasts of the Earth?"............. just as the hippo was about to turn head on to us I busted a 500 FN Solid through his neck and the show was over immediately. What a great shot you say? Yeah, HEH HEH....... especially since I was aiming just below his ear... LOL........... Oh well, it worked out just fine at 6 steps.............

I was pretty pleased with everything none the less. But I kept thinking what would have been a better handling fighting rifle? No, I don't do double anything, so don't go there...........

Upon my return a few weeks later one of my life long close friends and I were on the phone one night. He wanted a 500 S&W on a lever gun! I told him, not going to happen, Marlin and 1886 receivers for 45/70 were too big. M94 receivers were too small. Needed a receiver in between (Later Big Horn did just that), but this was late 2005. At that time I had been playing with a 338 WSM, had a WSM rifle on hand, I looked at the cartridge, did some quick measurements on it, and got the hacksaw out and cut a case down and trimmed it to 1.65 inches........ and it would hold a .500 caliber bullet just fine! And on top of that, seemed to work just fine in a WSM Action! I told him, can't give you a lever gun, but I can give you a bolt gun!

Later that night, I could not get something out of my head, sure, the 1.65 inch WSM case fit the WSM magazine, bolt face, and seemed to feed fine, but I had a LOT Of Magazine Space there..... What other Case or Cartridge would be close to the same........ "Light Bulb" time........ RUM!!!!! Next morning, first thing, I had RUM cases for something, I think maybe 300 or 338.... But I cut one of those down to 2.250 and like magic it was the right length and size for the WSM magazine, bolt face, the works............ Now what capacity is this, would this be effective in a much shorter smaller rifle? Case capacity was about equal with 458 Winchester, so I had enough capacity. But there was a major problem, I did not have bullets that would work at the velocities this cartridge could churn up. So I split the difference and shortened the case to 1.950.... just short of 2 inches, I was not very smart at the time, I should have just stayed at 2 inches, but in the long run it worked out for something else down the road............

I touched base with SSK and got JD and Brian to work on this .500 caliber cartridge. At the same time I had them go to work on a 2.25 inch 458 Version as well....... with 458 being dear to my heart.

I had the first prototype .500, 50 B&M at 1.95 inch RUM case rifle, with 18 inch barrel around February of 2006. Of course, Win M70 WSM Control feed action. I started work with all the available bullets at the time, all designed for 500 S&W velocities. The 1.95 inch .500 case was about equal to 45/70 velocities, running 500 Hornady at 1850 fps, 400 Sierras at 2100 fps, and some various lighter bullets around 2000-2100 fps as well...... April of 2006 I found myself on a whirlwind shooting spree in South Africa.... I had already tested all bullets for Terminals, now field work to confirm. I love 45/70, but have had 45/70 in the field many times prior, and I expected these bullets at near 45/70 velocity to perform like 45/70s..... a little short of fantastic. I was wrong, .500 caliber made a difference, a big difference.

Could this be the Platform I was looking for? Shorter, lighter, faster, and far more handy, a dandy Beast Fighting rifle! Hmmm...............But bullets available were not up to "Speed" so to speak, not for buffalo/hippo or elephant......... Not Yet!

It was May of 2007 before the first 458 B&M finally arrived, dies and reamer had taken longer than expected........... First rifle had 20 inch barrel, since we were still trying to figure out what the cartridges could do, I went with 20.......... Which equaled and in some cases went slightly beyond 458 Win. We had pretty decent bullets back then, I favored 450s in the rifles and they did great with that weight.

By 2007 JD had helped me discover CNC Machined bullets, this solved the .500 caliber issues completely. Later in 2007 I found myself in Zimbabwe testing many of these bullets, made by Lehigh at the time. I had a pretty decent solid in the 50 B&M, which had now graduated to full length at 2.250 inches, because I now had bullets that would handle those velocities. I was shooting a 510 gr Solid in the 50, with its 18 inch barrel at 2125 fps. This bullet proved itself on a couple of elephants that year and several buffalo.

The Platform was now mated with a Cartridge and Bullets that indeed could be that very short, very fast handling rifle needed to Take on the Mighty Beasts of the Earth. Not only that, but it was light enough and short enough to not be such a damn burden on those long long days in the field.

The various .500 caliber B&Ms and of course the 458 B&M were used for this purpose for the rest of my hunting days, I never went to the field again with a 24 inch 10 lb musket........ all of them were retired, later many sold...... I still have one Custom Shop Win M70 458 Lott that I took 4 elephants with and several buffalo, I sitll have the #13 African Edition 458 Lott, although I whacked that barrel to 22 inches and added NECG Barrel Band front.......... I still have my Lion Rifle, Win M709 458 Winchester 22 inch gun, and a newer Win M70 458 Winchester that I cut to 20 inches and put NECG Barrel band on as well...........

My favorite 458 is my Bastogne 18 inch Gun Kote finish 458 B&M........ It served up everything needed, from impala to elephant and all in between, hippo and buffalo........ in a 7.5 lb package 38 inches overall length and pleasure to work with all day in the field...........

No it has nothing to do with the Cartridge, but the combination of the Platform, Cartridge, and most important the Bullet! It takes all three to be successful...........

But, without doubt, Building a new rifle can be a pain in the ass, you also have to consider you have to Hand Load for this as well........ If you do not hand load, and you don't care for a custom build, then by all means get yourself a Winchester M70 458 Winchester and call it a day, you won't come up short, literally....... but you would benefit from whacking it down a little to gain some handling ability, and a bit easier to work with all day in the field...........

My 20 inch 458 Winchester.............Shorter, but it is a little heavy still, but I won't be taking it out anyway...........

 

[hoytcanon]

Well, if one can ONLY choose ONE Rifle/Cartridge, then I would not really disagree with that statement, you can come out very well with a good ole 458 Winchester and never need for more, or even less....... Did not expect that eh?
My 20 inch 458 Winchester.............Shorter, but it is a little heavy still, but I won't be taking it out anyway.....

View attachment 651206

Well... that was a mouth full... when it comes to posting, I am more Dr.Seuss than Shakespeare...

I 100% get messing around to make things work for you, and the reasons for doing so are your own. I have been going the Carbine route with funky cartridges for decades, they just work for the way I hunt in the areas I hunt and for the game I hunt.

I just made one of your "RAT Guns" in a .375 WSM to take for PG in March. My Ruger M77 Mark II Stainless Carbine .458 WM is an all around carry when guiding for bears, light, quick and handy, with a heavy payload. They make sense to me.

Continue building and experimenting, it advances the whole data base available to the shooting community.

 

[Altitude sickness]

Win M70 458 Winchester that I cut to 20 inches and put NECG Barrel band

Michael, how does the factory Model 70 perform with the 20” barrel. Is there a bullet you like with the factory rifling ratio.

 

[michael458]

Win M70 458 Winchester that I cut to 20 inches and put NECG Barrel band

Michael, how does the factory Model 70 perform with the 20” barrel. Is there a bullet you like with the factory rifling ratio.

First my main mission here was to see if I could get the rifle/cartridge at 20 inches viable for the heavies, buffalo, elephant and hippo. This needed to be a 450 Gr #13 CEB Solid at MY minimum of 2150 to 2200 fps. I did that without issue at all.......... I was busy with some other things we wanted to investigate, so I never really tested the Matching 420 Raptors, which I am sure I would have been over 2300 fps with those, which would have been just dandy for buffalo ++...............

Ron and I both were very interested in the 404 Hammers, he and LDMay375 both sent plenty of samples for me to test both load data and Terminals....... From the Terminal work done, we declared the 404 Hammer very Buffalo Capable. I think someone here did use it with great success after this for buffalo.

Another primary interest for me was the 250 CEB Socom Raptors, which I have used many times on plains game and found deadly on everything shot with it, many zebra, wildebeest+++++...........

458 Winchester is very capable at 20 inches, especially if you combine proper Bullet Tech. I can't fathom why shooters are still insisting on various 500 gr bullets in .458 caliber...........

8/7/22	450 #13 Solid	76/IMR 8208	Fed 215	2272	2270	2	2271	62100 PSI—Oehler—COL 3.282
			Match	63500	60600	2900	62100	LabRadar Velocity
8/7/22	450 #13 Solid	74/IMR 8208	Fed 215	2237	2226	12	2231	60000 PSI—Oehler—COL 3.282
			Match	61600	58400	3200	60000	LabRadar Velocity
8/13/22	450 #13 Solid	75/X Terminator	Fed 215	2246	2234	11	2240	59900 PSI
		102021 Blend		60100	59600	500	59900	COL 3.285
8/10/22	404Hammer	80/AA 2230	Fed 215	2388	2364	24	2376	61400 PSI—COL 3.280—@25yds 2324 fps
		2022 Blend	Match	62500	60300	2200	61400	Norma Brass—PACT15ft 2359 fps
11/3/22	400 #13 Solid	86/TAC	Fed 215	2421	2414	7	2418	58700 PSI —- COL 3.290”
				59200	58200	1000	58700	Loaded Carefully for No Bulge
8/11/2022	250 Socom	78/H-4198	Fed 215	2857	2839	18	2848	53800 PSI—COL 3.325—WW Brass
				54600	52900	1700	53800	Seat 2cd Groove Down

 

[Altitude sickness]

It’s hard to go back to “musket length” as you say

Here is my .416 Taylor with 21” barrel. It likes the 400 gr CEB solid and 370 Raptor. Shown is 3 shots from each (with a scope installed)

 

[rosenberger stephen]

Well, if one can ONLY choose ONE Rifle/Cartridge, then I would not really disagree with that statement, you can come out very well with a good ole 458 Winchester and never need for more, or even less....... Did not expect that eh?................. Well, let me tell you a little story............

I did not come up with the B&M Cartridges by trying to improve on any existing cartridges! My goal was not "Cartridge" Oriented. I did not set out to make a bigger, better, faster .458 caliber cartridge, that had little or nothing to do with it.

It had everything to do with the "Platform" that the Cartridge is based upon!

I late 2005 all the stars, Sun and Moon were in alignment............

October 2005 found me and my lovely Wife in Tanzania. I was after Buffalo mostly and then whatever else came within sights........... I was carrying a Winchester M70 458 Lott African Edition #50. They only made 50 of these, I had #50 and #13 of the series. This 458 Lott still had a Musket barrel of 24 inches, came in with scope probably around 10-10.5 lbs. For my small caliber gun I had a Winchester M70 416 Remington, was mostly shooting the 340 Woodleighs that year, I would have to look at the exact load and velocity, but it proved to do a decent job on zebra and such, one and only leopard I had ever taken and a charging Roan. I liked the bullet, so good that for a conventional bullet I used my leftovers not so long ago for shelf ammo for my own 416 B&Ms........

Now, back to a real rifle and cartridge, 458 Lott........... That year I was using a combination 500 Swift A Frame and 500 Barnes FN Solids........ Proved to be an excellent combination on several buffalo, and I was astounded at just how hard the 500 Barnes Solids hit up front, a vast difference from the old RN versions........ You could see buffalo react to taking that FN Solid.......

We got involved in an Altercation between two bull hippos one day. We just happened to be there in the right/wrong place to witness the after effects. The looser of the ordeal was not very happy, and spotted us up above him and here he came. Now the bank we were standing on was too steep for him to come direct, so in a round about way he made his way up to us. This seemed to take a long time in my mind. Now I was ready, up in arms you might say, with a very very very LONG Musket size gun, that now felt like it weighed in at 25 ++++ Lbs, I was getting weak in the arms holding this thing, this fat, long, overweight 458 Lott! In this time I was thinking to myself "God there has to be something better than this to fight the beasts of the Earth?"............. just as the hippo was about to turn head on to us I busted a 500 FN Solid through his neck and the show was over immediately. What a great shot you say? Yeah, HEH HEH....... especially since I was aiming just below his ear... LOL........... Oh well, it worked out just fine at 6 steps.............

I was pretty pleased with everything none the less. But I kept thinking what would have been a better handling fighting rifle? No, I don't do double anything, so don't go there...........

Upon my return a few weeks later one of my life long close friends and I were on the phone one night. He wanted a 500 S&W on a lever gun! I told him, not going to happen, Marlin and 1886 receivers for 45/70 were too big. M94 receivers were too small. Needed a receiver in between (Later Big Horn did just that), but this was late 2005. At that time I had been playing with a 338 WSM, had a WSM rifle on hand, I looked at the cartridge, did some quick measurements on it, and got the hacksaw out and cut a case down and trimmed it to 1.65 inches........ and it would hold a .500 caliber bullet just fine! And on top of that, seemed to work just fine in a WSM Action! I told him, can't give you a lever gun, but I can give you a bolt gun!

Later that night, I could not get something out of my head, sure, the 1.65 inch WSM case fit the WSM magazine, bolt face, and seemed to feed fine, but I had a LOT Of Magazine Space there..... What other Case or Cartridge would be close to the same........ "Light Bulb" time........ RUM!!!!! Next morning, first thing, I had RUM cases for something, I think maybe 300 or 338.... But I cut one of those down to 2.250 and like magic it was the right length and size for the WSM magazine, bolt face, the works............ Now what capacity is this, would this be effective in a much shorter smaller rifle? Case capacity was about equal with 458 Winchester, so I had enough capacity. But there was a major problem, I did not have bullets that would work at the velocities this cartridge could churn up. So I split the difference and shortened the case to 1.950.... just short of 2 inches, I was not very smart at the time, I should have just stayed at 2 inches, but in the long run it worked out for something else down the road............

I touched base with SSK and got JD and Brian to work on this .500 caliber cartridge. At the same time I had them go to work on a 2.25 inch 458 Version as well....... with 458 being dear to my heart.

I had the first prototype .500, 50 B&M at 1.95 inch RUM case rifle, with 18 inch barrel around February of 2006. Of course, Win M70 WSM Control feed action. I started work with all the available bullets at the time, all designed for 500 S&W velocities. The 1.95 inch .500 case was about equal to 45/70 velocities, running 500 Hornady at 1850 fps, 400 Sierras at 2100 fps, and some various lighter bullets around 2000-2100 fps as well...... April of 2006 I found myself on a whirlwind shooting spree in South Africa.... I had already tested all bullets for Terminals, now field work to confirm. I love 45/70, but have had 45/70 in the field many times prior, and I expected these bullets at near 45/70 velocity to perform like 45/70s..... a little short of fantastic. I was wrong, .500 caliber made a difference, a big difference.

Could this be the Platform I was looking for? Shorter, lighter, faster, and far more handy, a dandy Beast Fighting rifle! Hmmm...............But bullets available were not up to "Speed" so to speak, not for buffalo/hippo or elephant......... Not Yet!

It was May of 2007 before the first 458 B&M finally arrived, dies and reamer had taken longer than expected........... First rifle had 20 inch barrel, since we were still trying to figure out what the cartridges could do, I went with 20.......... Which equaled and in some cases went slightly beyond 458 Win. We had pretty decent bullets back then, I favored 450s in the rifles and they did great with that weight.

By 2007 JD had helped me discover CNC Machined bullets, this solved the .500 caliber issues completely. Later in 2007 I found myself in Zimbabwe testing many of these bullets, made by Lehigh at the time. I had a pretty decent solid in the 50 B&M, which had now graduated to full length at 2.250 inches, because I now had bullets that would handle those velocities. I was shooting a 510 gr Solid in the 50, with its 18 inch barrel at 2125 fps. This bullet proved itself on a couple of elephants that year and several buffalo.

The Platform was now mated with a Cartridge and Bullets that indeed could be that very short, very fast handling rifle needed to Take on the Mighty Beasts of the Earth. Not only that, but it was light enough and short enough to not be such a damn burden on those long long days in the field.

The various .500 caliber B&Ms and of course the 458 B&M were used for this purpose for the rest of my hunting days, I never went to the field again with a 24 inch 10 lb musket........ all of them were retired, later many sold...... I still have one Custom Shop Win M70 458 Lott that I took 4 elephants with and several buffalo, I sitll have the #13 African Edition 458 Lott, although I whacked that barrel to 22 inches and added NECG Barrel Band front.......... I still have my Lion Rifle, Win M709 458 Winchester 22 inch gun, and a newer Win M70 458 Winchester that I cut to 20 inches and put NECG Barrel band on as well...........

My favorite 458 is my Bastogne 18 inch Gun Kote finish 458 B&M........ It served up everything needed, from impala to elephant and all in between, hippo and buffalo........ in a 7.5 lb package 38 inches overall length and pleasure to work with all day in the field...........

No it has nothing to do with the Cartridge, but the combination of the Platform, Cartridge, and most important the Bullet! It takes all three to be successful...........

But, without doubt, Building a new rifle can be a pain in the ass, you also have to consider you have to Hand Load for this as well........ If you do not hand load, and you don't care for a custom build, then by all means get yourself a Winchester M70 458 Winchester and call it a day, you won't come up short, literally....... but you would benefit from whacking it down a little to gain some handling ability, and a bit easier to work with all day in the field...........

My 20 inch 458 Winchester.............Shorter, but it is a little heavy still, but I won't be taking it out anyway...........

 

[rosenberger stephen]

Thank You for the detailed summary of the origin. Makes sense to me now. I imagine the recoil in a 7.5 lb. rifle is quite stiff but probably not much more than an 8 lb. Browning with 510 grain factory ammo, plus you are apparently used to such recoil.

 

[ldmay375]

First my main mission here was to see if I could get the rifle/cartridge at 20 inches viable for the heavies, buffalo, elephant and hippo. This needed to be a 450 Gr #13 CEB Solid at MY minimum of 2150 to 2200 fps. I did that without issue at all.......... I was busy with some other things we wanted to investigate, so I never really tested the Matching 420 Raptors, which I am sure I would have been over 2300 fps with those, which would have been just dandy for buffalo ++...............

Ron and I both were very interested in the 404 Hammers, he and LDMay375 both sent plenty of samples for me to test both load data and Terminals....... From the Terminal work done, we declared the 404 Hammer very Buffalo Capable. I think someone here did use it with great success after this for buffalo.

Another primary interest for me was the 250 CEB Socom Raptors, which I have used many times on plains game and found deadly on everything shot with it, many zebra, wildebeest+++++...........

458 Winchester is very capable at 20 inches, especially if you combine proper Bullet Tech. I can't fathom why shooters are still insisting on various 500 gr bullets in .458 caliber...........

8/7/22	450 #13 Solid	76/IMR 8208	Fed 215	2272	2270	2	2271	62100 PSI—Oehler—COL 3.282
			Match	63500	60600	2900	62100	LabRadar Velocity
8/7/22	450 #13 Solid	74/IMR 8208	Fed 215	2237	2226	12	2231	60000 PSI—Oehler—COL 3.282
			Match	61600	58400	3200	60000	LabRadar Velocity
8/13/22	450 #13 Solid	75/X Terminator	Fed 215	2246	2234	11	2240	59900 PSI
		102021 Blend		60100	59600	500	59900	COL 3.285
8/10/22	404Hammer	80/AA 2230	Fed 215	2388	2364	24	2376	61400 PSI—COL 3.280—@25yds 2324 fps
		2022 Blend	Match	62500	60300	2200	61400	Norma Brass—PACT15ft 2359 fps
11/3/22	400 #13 Solid	86/TAC	Fed 215	2421	2414	7	2418	58700 PSI —- COL 3.290”
				59200	58200	1000	58700	Loaded Carefully for No Bulge
8/11/2022	250 Socom	78/H-4198	Fed 215	2857	2839	18	2848	53800 PSI—COL 3.325—WW Brass
				54600	52900	1700	53800	Seat 2cd Groove Down

That is only a small snapshot of the bullet combinations that you tested for me in the different.458 cartridges.

I think the 458 B&M at its case length, and the 500 B&M at its longer case length make for fine cartridge platforms for compact rifles with some diameter and horsepower.

This I do know about Michael458, he is not trying to sell shat. Nor convert or convince people to B&M cartridges. I do not own one. But, if not already overrun with mainstream .416's & .458's before I was really aware of them, I would. Specifically the 458 and 500 B&M versions.

I think this needs to be re-said, for those that are not already aware. Michael458 is not in the rifle nor bullet business, makes Zero funds from rifles made with B&M cartridges or any cartridges or bullets. He shares his acquired experience freely, even with those of us that may still continue to fire a round or two of .375 bullets. He was a gigantic help to me, for developing 458 Winchester and 458 Lott loads to use on North American type animals. That opened another dimension of use, other than Buffalo Busters, for those of us that like shooting .458 cartridges.