belted magnum question

Elevendysixty

Well-Known Member
Joined
Sep 4, 2012
Messages
94
Location
Pittsburgh-ish
i have a limited amount of reloading experience and have recently purchased a belted magnum chambered rifle and have zero experience with a belted case. i understand (i think) that not actually full length sizing with a full length sizing die is important for case life. I've done a fair amount of reading and I'm still unsure of the process of sizing off the shoulder. i was hoping it wouldn't be too time intensive of a task for someone to type/link a beginner's how to guide. thanks for the assistance.
 
i have a limited amount of reloading experience and have recently purchased a belted magnum chambered rifle and have zero experience with a belted case. i understand (i think) that not actually full length sizing with a full length sizing die is important for case life. I've done a fair amount of reading and I'm still unsure of the process of sizing off the shoulder. i was hoping it wouldn't be too time intensive of a task for someone to type/link a beginner's how to guide. thanks for the assistance.

It's easy. The first firing will headspace of the belt no matter what. On the subsequent loads, the brass will completely fireform to the chamber. To headspace off the shoulder adjust the die to where it neck sizes only, or bumps the shoulder .001 to ease chambering the round if it gets tight.

For neck sizing with a standard die, twist the die down where there is a space about the thickness of a penny between the shellholder and the bottom of the die, run a piece of brass through and check to see if the neck is sized down to the shoulder. If it's not completely sized, twist the die down in small increments until the the entire neck is sized.
 
Check this place out:
reloadingindex
Check out the sizing page and the following sizing for rimmed and belted cases. That may explain a little bit.
As already stated, when you chamber this round, it will stop in the chamber when the belt hits its little indent in the chamber; whereas other rounds stop once the shoulder hits the chamber.
Just use the "feel" method of sizing your cases... Put a fired case back in the chamber and close the bolt (remove the firing pin from the bolt so you can feel the movements better). Remember how that feels. Now, back the die off a bit, size a case, put it back in the chamber. Note how that feels in comparison. Keep sizing till you get a "snug" fit that allows the bolt to close without excess pressure - a little pressure is fine - no pressure at all is bad. You want the case to be almost the exact same size as your chamber. Be sure you have adequate neck tension when you find the best "sweet spot".

Hopefully you have a headspace measuring tool of some sort. If so, take several fired cases and measure them, using the largest one as a reference point. Size the cases and measure in the tool until you get around .001" - .002" shorter.

If you don't have a tool, get one. Some, like the Hornady LnL Case Headspace Gauge kit, which comes with bushings for various calibers, measures off the "datum line" of the shoulder. So does my favorite, the RCBS Case Mic. The best available, that I'm aware of, although I haven't had the priveledge of using one, the Sinclar Should Bump Gauge, measures off the shoulder, not the datum line. Both versions measure to give the same target task - however I feel the Sinclair does it with a bit more precision. I own the Hornady LnL kit, and one RCBS Case Mic, and recommend both.
 
It's easy. The first firing will headspace of the belt no matter what. On the subsequent loads, the brass will completely fireform to the chamber. To headspace off the shoulder adjust the die to where it neck sizes only, or bumps the shoulder .001 to ease chambering the round if it gets tight.

For neck sizing with a standard die, twist the die down where there is a space about the thickness of a penny between the shellholder and the bottom of the die, run a piece of brass through and check to see if the neck is sized down to the shoulder. If it's not completely sized, twist the die down in small increments until the the entire neck is sized.

I know this thread is old, but can you give me some help with a belt magnum? It is our first. We have been reloading for years. However, I bought a bunch of brass for it and they won't allow the bolt to lock down. It appears as if the belt section in the rifle is too shallow or these brass the belt is too wide. We bought some factory loads (Federal) and they went through the gun perfectly. I actually filed down a couple of the other brass until they fit in the gun. What is up with this? Do I need to take it to a gunsmith and have the belt chamber deepened? Tks.
 
I know this thread is old, but can you give me some help with a belt magnum? It is our first. We have been reloading for years. However, I bought a bunch of brass for it and they won't allow the bolt to lock down. It appears as if the belt section in the rifle is too shallow or these brass the belt is too wide. We bought some factory loads (Federal) and they went through the gun perfectly. I actually filed down a couple of the other brass until they fit in the gun. What is up with this? Do I need to take it to a gunsmith and have the belt chamber deepened? Tks.

Your headspace is too tight at the belt. Is it a factory rifle?
 
Just buy some neck-sizer dies and be done with it. By the time you will need to bump the shoulder back, the cases will probably need to be trashed for some new ones anyway.

Lots of people spread this BS that belted cartridges are some nightmare to load for, which is completely false. I've been loading for belted cases as long as non-belted, and no issues. Don't fall for the internet bullcrap.
 
Just buy some neck-sizer dies and be done with it. By the time you will need to bump the shoulder back, the cases will probably need to be trashed for some new ones anyway.

Lots of people spread this BS that belted cartridges are some nightmare to load for, which is completely false. I've been loading for belted cases as long as non-belted, and no issues. Don't fall for the internet bullcrap.
I never understood the belt issue. I've never had a problem with 7mm rem mag. My die is set for a .002 bump(its my hunting rifle so I want it to chamber freely) and my primer pockets go long before the get case head separation.
 
Yes, it is a factory rifle. How is that adjusted?

Is the brass that you bought new or used in another rifle. If it's new, you have two options. Either use brass with a belt that fits, or take it to gunsmith to see if he will adjust the headspace. It should only take a .001" more clearance to get the belt to fit.
 
Just buy some neck-sizer dies and be done with it. By the time you will need to bump the shoulder back, the cases will probably need to be trashed for some new ones anyway.

Lots of people spread this BS that belted cartridges are some nightmare to load for, which is completely false. I've been loading for belted cases as long as non-belted, and no issues. Don't fall for the internet bullcrap.
How the heck is a neck sizing die going to work when the brass does not fit back in the chamber?
Issues with belted mags are common and all you have to do is own a caliper to understand what's going on. Saying it's never an issue is pure ignorance!!
 
How the heck is a neck sizing die going to work when the brass does not fit back in the chamber?
Issues with belted mags are common and all you have to do is own a caliper to understand what's going on. Saying it's never an issue is pure ignorance!!
Starting with fresh brass in your rifle, neck-sizing should not be an issue after they've fire-formed, as long as your rifle's chamber and dies are properly setup. None of mine have been an issue in thousands of rounds.

I know what you're referring to, I own a caliper, I know what's going on. You're talking about measuring the web for expansion. A properly cut chamber won't have that issue. With a lack of knowledge, anything has the potential to be a f*** up.

Saying anything is never an issue is ignorance, but so is claiming something is, when it's most-likely operator error.
 
Starting with fresh brass in your rifle, neck-sizing should not be an issue after they've fire-formed, as long as your rifle's chamber and dies are properly setup. None of mine have been an issue in thousands of rounds.

I know what you're referring to, I own a caliper, I know what's going on. You're talking about measuring the web for expansion. A properly cut chamber won't have that issue. With a lack of knowledge, anything has the potential to be a f*** up.

Saying anything is never an issue is ignorance, but so is claiming something is, when it's most-likely operator error.

Not all belted magnum brass is created equal. Belts between brass makes have dimensional variance. As I understand the issue, the problem here is caused by new brass that has a thicker belt than the current headspace will allow to fit in the chamber. It has nothing to do with the web or shoulder.
 
Something is obviously wrong with the brass you bought. You haven't mentioned what caliber this is. I know this is a dumbA-- question. but here goes anyway... You did buy the correct caliber brass? If new factory loads are going in fine brand new brass should also. Run a few through a full resizing die and check brass length.
 
Warning! This thread is more than 6 years ago old.
It's likely that no further discussion is required, in which case we recommend starting a new thread. If however you feel your response is required you can still do so.

Recent Posts

Top