.358 umt ???

I've read a little about the .358 UMT {Ultra Mag Towsley} and this is all I known about it does anybody have one that can tell me more.

.358 UMT wildcat will push a 250-grain bullet to 3,100 ft/s and a 225-grain to 3,200 ft/s. That means it has more energy than a .416 Remington and shoots flatter than a .300 Winchester 180-grain.
It's a simple wildcat cartridge made by necking the .300 RUM up to 35-caliber with no other changes. The cartridge likes Swift A-Frame and Barnes TSX bullets best, most others are too soft. IMR 7828 is the best powder.
 
sounds like an interesting caliber. I have never herd of it so i cant help you out however i can tell you if its that hard to find information for then you might want to look elsewhere. It is very difficult to load something that you have no information for. There are so many great cartrages out there that have tons of information. Im not saying the 358 would not be great but just think about the difficulty of getting any help with it. Would be great if you could find someone and hope you do to help you out. If it comes through let us know and make sure you post some pics. Who knows you might start a new trend. :D
 
It talks about it in the new Hunter magazine. I went over to my fathers today and it was laying on the coffee table. The thing that caught my eye was that it's falter than a 7mm mag. and faster than a 300 win. mag.
 
It talks about it in the new Hunter magazine. I went over to my fathers today and it was laying on the coffee table. The thing that caught my eye was that it's falter than a 7mm mag. and faster than a 300 win. mag.

That does sound very intriguing and might possibly catch on as a long range calliber of choice for some. I say the best thing you could do to get more info is to get ahold of the editor of the magazine that wrote the article and see if they can give you some more info or point in the direction of someone who has one. Thats what i would do. Good luck
 
This would be a good cartridge but that caliber is severely lacking bullets compared to 338 and 375. The 338 Edge and 375 RUM are exactly the same case but in calibers with a better bullet selection. All three cases are identical, same shoulder, same length, just a different hole in front. With the lighter bullets the Edge will shoot flatter and faster than 358 UMT and with heavier bullets the 375 RUM will hit harder.

So this is just another good cartridge for which there is zero need.
 
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Yeah I read the article in the NRA mag that they talked about the 358.

There is no way you can consider that its flatter than a 7mm mag. The 358 bullets have bad bc under .4 and aren't much faster or even as fast.

On the flip side up close they sure would be a hammer! Over 5000lbs of energy would put a hurtin on about what ever you wanted.
 
If you want a real hammer get a 375 RUM!! Shoot the 350 SMK for long range or the 270 or 300 TSX for short range and dangerous game. Highly suitable, with proper bullet choice, for any big game anywhere other than elephant. And capable on elephant with a flat nose Barnes or North Fork solid.

If you want flatter and faster shoot the 7mm RUM or 300 RUM, same case again as 358 UMT. Higher BC bullets than the 358 and more speed.

Even the 338 RUM would be a better choice than the 358. The 338 RUM is a shorter case than 7mm RUM, 300 RUM, 338 Edge, or 375 RUM but not enough to make any real difference
 
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I sure do like mine, performs well with 200 gr ttsx or 225 tsx. Recoil is stiff but my rifle isn't one of the heavyweights either. Stainless 700 Bdl in a Rem stock. A friend of mine has the only other one known to be in Alaska, both were made by a professional barrel maker in AZ with a reamer I ordered out of OR. In 2009 a grown Alaskan Moose received 1 TTSX from a lasered 325 yds and promptly expired. He was good eating too! I have a 3-9 X 40 Pentax Lightseeker which has served me well. I don't shoot .338 and my 7MM is a SAUM (good for sheep or caribou), therefore I'm not sure about the comparison. I also have some cronygrapgh data at home tho I won't be there until 18 Jan. The fine folks in Nebraska made my dies from 3 fired cases. I'd be glad to share any more information I can about this rompin-stompin round.
 
When and if you get one let me know, we can compare notes, mine should be finished July or August. Bryce loaded it with 225 TSX, I'm gonna do the same. I'm also looking at getting a ULD from Corbin and making my own heavy BC Bullets for it.
 
Knowing that this post is ~4yrs old, I can't help but comment as the .358UMT has intrigued me since Bryce wrote about it all those years ago.

Is it a niche cartridge? Yep. But one has to admit it is still pretty bad ***. Why would one build it? Probably for the same reason anyone uses to build a wildcat, because they want to & they can. I built a .358STA some years ago, 225 Barnes @ 3000 fps... why not!?

The greater cross sectional area of the .358 should make a noticable difference in impact on big critter, especially at RUM velocities (most noticable <1k yds). Why isn't the .358 caliber more popular? Just as stated before, there are no viable long range bullets in said caliber. Would the UMT still kill elk @ 1kyds? Dern tootin'. Not to mention it should offer greater bore life than the 7mm, 300 & 338 RUMs respectively.

I think it would be a lot of fun personally, I've always tried to have the oddball cartridge in camp. That's why I chose the 7.82 Partriot over the 300WSM, that's why I chose the 6.5WSM, or the 22-243 over the 22-250 & the 6-284 over the .243 win.

In the end the question most often posed is: "Why?". The most simple answer is: "Because I can".


t
 
Knowing that this post is ~4yrs old, I can't help but comment as the .358UMT has intrigued me since Bryce wrote about it all those years ago.

Is it a niche cartridge? Yep. But one has to admit it is still pretty bad ***. Why would one build it? Probably for the same reason anyone uses to build a wildcat, because they want to & they can. I built a .358STA some years ago, 225 Barnes @ 3000 fps... why not!?

In the end the question most often posed is: "Why?". The most simple answer is: "Because I can".


t

Outlaw, I'm stealing your idea, I'm now calling my .358 Ultra Mag imp. a "Because I can" Ultra Mag. Hope that's okay
 
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