Reloader question for .458 Win Mag.

[Foxi]

Hello reloader.

Your collective wisdom is needed.
I use a double rifle, o/u, in .458 caliber and reload my own cartridges. Now I'm being told I should only resize belt cases up to the belt, not beyond.
Apparently, that weakens the case.
How do you resize your cases?
If I don't resize all the way down, only to the beginning of the belt, I can't close the rifle. So I have to resize it full.
Twice, the case broke off at the belt after firing.
Has anyone else experienced this?
How often do you reload these cases?
Do you consider Hornady cases (I always fire original ammunition to get the cases) to be of good quality?
My Ferlach shoots quite well.
Here's the result at 50 meters with a red dot sight.
The first shot on the right went off a bit too early for my liking.
It can sometimes be a men problem
Thanks for your answers.
Foxi

 

[deewayne2003]

Looks like you have excellent accuracy.

Being a belted magnum, have you considered the Larry Willis sizing die? It removes the slight bulge that develops in front of the belt.

Innovative Technologies - Reloading Equipment

Our patented resizing die can reload Winchester, Remington and Weatherby belted magnums up to 20 times, instead of just 2 or 3 times and the top of the die is a chamber width gauge.

www.larrywillis.com

It works on any belted cartridge with the same base as .458Win… .300Win, .375H&H, ect

 

[AJ Peacock]

I have zero .458 experience, but a lot of experience in reloading belted cartridges. I only push the shoulder back a couple thousandths and do not size the body. But this is with Bolt rifles, it is likely that a double may behave differently from an insertion/extraction perspective.
Can you post a picture of the case failures?

AJ

 

[Mark A Ouellette]

Hey @Foxi

I load .458 WIn for my trusty Heym double rifle.
In almost 800 shots I've experianced thinning of the case wall just above the belt as my only case problem.
I full length size.
I've never had a neck crack even without anealling. This is porbably because I can load perhape 5 times without case wall thinning.

Shown are 500/416 cases which for me had the same case wall thinning problem as my .458 Win cases.
One can see a lighter ring start to be visable with case wall thinning. The gage just allows me to determine how much life remains in a case.

PS: I use a Larry Willis sizing die but that process does nothing to reduce case wall thinning on my .458 Win cases.

PSS: Hornady brass is okay but is never my first choice. It is however usually more available than other brands.

 

[Foxi]

I have zero .458 experience, but a lot of experience in reloading belted cartridges. I only push the shoulder back a couple thousandths and do not size the body. But this is with Bolt rifles, it is likely that a double may behave differently from an insertion/extraction perspective.
Can you post a picture of the case failures?

AJ

@deewayne .
never heared of this.
Don't know so it is avaliable in Europe.
Thank you

 

[AJ Peacock]

Thanks for the pictures, classic case separation.
Do a google for "belted case separation" and you'll find a ton of information regarding causes/fixes.

Since the 458 is tapered and not 'shouldered', I don't know what I'd do.

AJ

 

[Foxi]

Hey @Foxi

I load .458 WIn for my trusty Heym double rifle.
In almost 800 shots I've experianced thinning of the case wall just above the belt as my only case problem.
I full length size.
I've never had a neck crack even without anealling. This is porbably because I can load perhape 5 times without case wall thinning.

Shown are 500/416 cases which for me had the same case wall thinning problem as my .458 Win cases.
One can see a lighter ring start to be visable with case wall thinning. The gage just allows me to determine how much life remains in a case.

View attachment 761259

PS: I use a Larry Willis sizing die but that process does nothing to reduce case wall thinning on my .458 Win cases.

PSS: Hornady brass is okay but is never my first choice. It is however usually more available than other brands.

That makes sense. I'm afraid I've downloaded it too many times. I won't do that anymore. Four or five times, and that's it.

Thanks

 

[C.W. Richter]

Larry above is RIP. Innovative Technologies was backlogged on orders, but that's a great idea for any HH based cartridges with issues. Handloaded many cartridges in the HH case (incl. 458, Wbys, A-Sq, but exceedingly 300 WM.) 'Have had the bulge in 300 WM on occasion (or NK sized for one gun and then getting caught up in another (son's) chamber. In that case, I ran the loaded ammo through an open 458 WM FL die and corrected the issue (standardized case ODs). There are other mfrs of "collet" re-sizing dies, that should take care of the problem. IF cases are resized too many times in particular cartridges, there will be thin spots and issues (cracks/blowouts). Also, excess headspace causes what your photos show as well! With bolts, as a quick test, we take a piece of scotch tape on the case head-does the gun lock up as normal, or is there resistance/or does it simply not close? Can you put several pieces in and close the action?? {Too much headspace >0.003" (0.001"-0.003" for 458 with 0.002 being ideal) can lead to problems.} You also need to re-size the entire case down to the belt. You don't want to crush the case/damage from the belt down, but you also don't want to leave brass hanging out in the breeze to bulge during reloading. One final comment-I've seen issues caused by people not trimming brass (necks) to the appropriate (reloading) dimension of 2.490" (for 458 WM). This can do funny things to cases/loads upon closing the action, if too tight (case is too long for the chamber). The HH case is one for stretching in many calibers, so trimming is a must! Again, have had issues with the bulge, but never case head separation (even with the hottest handloads.) I find Win brass best for most applications (happy medium-as there are cheaper and then super hard like Norma-which is great, but can cause overpressure situations in certain cartridges if preparing your same pet loads used in another (softer, more apt to stretch/soak up some P) mfrs. Again, never blew a Norma case head off (split necks, blown primers occasionally in extremely HOT climates.) GL and report back when you've taken care of the issue! Chamber casts might be a good idea, too. I've never seen an O/U or S/S .458 Win Mag (as it was made to match straight-walled, Rimless NE cartridge velocities in newer, shorter bolt actions.)

 

[C.W. Richter]

And you never thought your wife had a head-spacing checker kit! Std. Scotch Tape 0.0025" (perfect for 458!) HD Packaging Tape 0.003". Some are as little as 0.15, so it's best to measure. 0.001"=1 MIL

 

[C.W. Richter]

Sry I meant Rimmed in the above commentary. The only rimmed ever owned were .30-30 as a kid, a few old hunting pistols I gave up on (as they became so heavy and expensive and some one-lungged game ran away-a rifle just made ideal sense) and .22 WMR which i so love to this day! You'll correct this issue, I'm sure.

 

[Schüler Jumbo]

A belted case stretches above the belt towards the case mouth. Full length resizing leads to work hardening the body and thus fatigue fracturing in front of the belt. I recommend you measure the length of a fired case because slight trimming may be all that is needed for your double to close. Measure fired cases of both the upper and lower barrels.