Quick Question: why is there a belt on Belted magnum

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it worked back then for head space…. so why fix not broken???

I personally never seen a rim case I didn’t like[/QUOTE

Headspace on the shoulder is more precise. In fact, you can adjust your die to make any belted mag headspace that way.
 
The thread centers around belt vs shoulder fit. So there is an unasked question of why isn't the belt "performing" as intended?

Has anyone who owns a belted rifle checked a new unfired round (headspaced on the shoulder) against the head clearance (space between head and bolt face) AND the fit of the belt to chamber?

I have no magnum firearms, but this is a good conversation.
 
The belt works as intended but if your don't watch and setup your dies on the shoulder you will have short brass life due to case head failure. It's been decades since I've had any factory ammo for my Rem 7mm Mag. But if I recall if you set your dies down to contact the shell plate you've over shot the shoulder position by quite a bit. I load for several 7mm Mags and use the RCBS Precision Mic to setup and adj my dies. One gun is way tighter than the other. I know how much shim to install under the die's lock ring when I load for it. I setup my dies like I would any std rifle cartridge, 0.001" shoulder clearance.
 
As an aside, I find it somewhat upsetting that Hornady/Marlin designed the 450 Marlin with an extra wide belt. They could have based it on the 458 magnum, so shooters would have the opportunity to make brass from other magnum cases in times of need. Instead, you have to get brass from Hornady, or not at all as is the case right now.

As it stands now, I find no reason to purchase a 450 Marlin rifle over a standard 45-70.
 
The belt works as intended but if your don't watch and setup your dies on the shoulder you will have short brass life due to case head failure. It's been decades since I've had any factory ammo for my Rem 7mm Mag. But if I recall if you set your dies down to contact the shell plate you've over shot the shoulder position by quite a bit. I load for several 7mm Mags and use the RCBS Precision Mic to setup and adj my dies. One gun is way tighter than the other. I know how much shim to install under the die's lock ring when I load for it. I setup my dies like I would any std rifle cartridge, 0.001" shoulder clearance.
dang, I don’t load alot of rifle ammo, I might pull my 7mm and start over, I was necking down 8mm rem mag to get 7stw cases
 
As an aside, I find it somewhat upsetting that Hornady/Marlin designed the 450 Marlin with an extra wide belt. They could have based it on the 458 magnum, so shooters would have the opportunity to make brass from other magnum cases in times of need.

I understand that their reason was to not give shooters the opportunity to put a .458 cartridge in a 7mm rifle.
Also, why let them make brass instead of buying it? I doubt they anticipated the current shortages.
 
I understand that their reason was to not give shooters the opportunity to put a .458 cartridge in a 7mm rifle.
Also, why let them make brass instead of buying it? I doubt they anticipated the current shortages.

I believe their actual a reason was the second one. Force them to buy brass from the one supplier.

I do not know which 7mm rifle you could actually chamber a 450 in even without the belt. The 450 is certainly too long to chamber in a 7mm Remington Magnum.
View attachment 1055416
 
No, it won't. 300 black and a 223 have the same overall length. That 30 caliber bullet would not fit in a chamber with a 22 caliber neck.
you sure about that, everyone warn me to label my 300blk mags because it would chamber in 5.56
 
you sure about that, everyone warn me to label my 300blk mags because it would chamber in 5.56

Look up the dimensions yourself. I suppose an empty 300 black case would chamber, but empty won't fire. I guess if you tried force feed a round, it would shove the bullet back into the case and then there would be a problem. In that case, I would say the Darwin Award would be warranted. You can't fix stupid.

Anyway, there are plenty of short action cartridges that would chamber in a long action rifle if you are dim or drunk enough to do so.

The only case of wrong ammo in the wrong gun I am personally familiar with lately is a 270 in a 30-06 and all that did was turn the 270 case into a 30-06.
 
Part of the reason that the belt has clung to the bottom of our shoes for so long is just due to how cartridges cases are made.

The forming dies for cartridge brass is very expensive equipment and brass manufactures like being able to make brass in production runs without having to change over a lot of equipment.

Here is the general forming process for brass. The part I'm getting at here is that the 2nd to last forming here which has the case head formed and straight walls is sometimes called a basic case. Since 90% of cartriges sold are based on just a handful of case head sizes, that means that the same basic brass can then be processed into a dozen or more other cartridges by just adding the appropriate shoulder and neck. So if you want to introduce a brand new cartridge, it will be much more efficient to produce it if you can keep the majority of dimensions the same as some other cartridge case that you are already making in large volume.

The belt was originally used on the .400/375 Nitro and it was a very good idea for giving something to head space off of on highly tapered or straight wall cartridges that have to feed from a magazine without a rim. Then it got carried onto the 375 H&H, and then the 375 H&H brass was used to spawn about 50 other cartridges that don't need a belt, but it was a production expedient to just use the H&H basic case and nobody ever bothered to get rid of it.

drawset20mmx300.jpg
 
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Ooooh no, that’s one internet lure that I take pretty seriously and believe.

I see your point. I wonder if that illustration was with an empty cartridge case. I also wonder if a normal powder charge would compress and stop the process. I guess I will never find out since I don't have an AR15 223, nor do I have one in 300 Black.

We had a saying in my line of work. "Beat to fit, and paint to match." Meaning you could always force fit something if you had a big enough hammer. It looks to me like the AR15 provides it's own hammer at the push of a button.

I have been trying to visualize how that situation could arise. The only way I can see it is if you grabbed a magazine preloaded with 300 Blk, and then grabbed a 223 AR15 by mistake. Without noticing that you grabbed the wrong gun because your 223 AR15 and your 300 Blk AR15 are exactly the same right? After all I have a bunch of identical guns in my safe? Then, not notice that the hole at the end of the barrel is grossly smaller than the bullet in your ammo? Like I said, oblivious.

It would have to be an AR, because you would have to force things pretty good in a bolt action to force it to fit.
 
I see your point. I wonder if that illustration was with an empty cartridge case. I also wonder if a normal powder charge would compress and stop the process. I guess I will never find out since I don't have an AR15 223, nor do I have one in 300 Black.

We had a saying in my line of work. "Beat to fit, and paint to match." Meaning you could always force fit something if you had a big enough hammer. It looks to me like the AR15 provides it's own hammer at the push of a button.

I have been trying to visualize how that situation could arise. The only way I can see it is if you grabbed a magazine preloaded with 300 Blk, and then grabbed a 223 AR15 by mistake. Without noticing that you grabbed the wrong gun because your 223 AR15 and your 300 Blk AR15 are exactly the same right? After all I have a bunch of identical guns in my safe? Then, not notice that the hole at the end of the barrel is grossly smaller than the bullet in your ammo? Like I said, oblivious.

It would have to be an AR, because you would have to force things pretty good in a bolt action to force it to fit.
I seen to many video of people putting 300blk in .223 chamber and firing, it loaded smoothly without force because the case is the same, just shorter and necked up
 
I see your point. I wonder if that illustration was with an empty cartridge case. I also wonder if a normal powder charge would compress and stop the process. I guess I will never find out since I don't have an AR15 223, nor do I have one in 300 Black.

We had a saying in my line of work. "Beat to fit, and paint to match." Meaning you could always force fit something if you had a big enough hammer. It looks to me like the AR15 provides it's own hammer at the push of a button.

I have been trying to visualize how that situation could arise. The only way I can see it is if you grabbed a magazine preloaded with 300 Blk, and then grabbed a 223 AR15 by mistake. Without noticing that you grabbed the wrong gun because your 223 AR15 and your 300 Blk AR15 are exactly the same right? After all I have a bunch of identical guns in my safe? Then, not notice that the hole at the end of the barrel is grossly smaller than the bullet in your ammo? Like I said, oblivious.

It would have to be an AR, because you would have to force things pretty good in a bolt action to force it to fit.

I have tried it myself just out of curiosity with a dummy loaded 300 blackout cartridge, and the closing bolt is indeed enough force to push the bullet back into the case far enough for the bolt to go into battery with a 300 blackout round in a 223 chamber. Some bullets profiles are more likely than others to be able to push far enough back, but I have tried it and it can happen.

The instances where I have heard of it happening in real life have been just as you guessed, someone picked up a mag full of 300 blackout and shoved it home in a 223. For this reason I never leave a magazine loaded with 300 blackout. I only load the mag at the time I am going to go shoot it.
 
I have tried it myself just out of curiosity with a dummy loaded 300 blackout cartridge, and the closing bolt is indeed enough force to push the bullet back into the case far enough for the bolt to go into battery with a 300 blackout round in a 223 chamber. Some bullets profiles are more likely than others to be able to push far enough back, but I have tried it and it can happen.

The instances where I have heard of it happening in real life have been just as you guessed, someone picked up a mag full of 300 blackout and shoved it home in a 223. For this reason I never leave a magazine loaded with 300 blackout. I only load the mag at the time I am going to go shoot it.

Alright now, that is certainly good enough for me. I will put that one in my "learned something" box. Thanks for the report on your actual test. I don't think I could set the bullet back in my single shot 223. My thumb isn't strong enough.:)
 
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