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Discussion Starter · #1 ·



Both are 8X57mm loaded 1 time with a heavy charge. My next loading is going to me much milder then theses ones. Are these beyond use?
 

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That expansion is above the web portion of the case, and is really more indicative of a loose rear-end of the chamber, not the heavy load. A litghter load would likely have resulted in the same thing.

My amatuer recommendation: Size them and load.

-Nate
 

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I'm looking to see the condition of fired cases at their mouth and with the primers still in them. Any signature of overpressure will be visible there.
 

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Klopinger said:
So would that mean my overal length is too short? Or the bolt face is loose?
Neither, it would mean that the overall diameter of the back end of the case is apprecialbly larger than your casing. Thus, at ignition, the case swells to meet those chamber walls. The webbing of the case is to thick, and the brass too hard to expand to that degree, so the thinner softer brass ahead of it creates the ring you see.

Chambers like this are usually cut so for reasons of reliability, but it is often a tradeoff for case life. Sorry 'bout that...

-Nate
 

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In a case like this, would this be considered appropriate fireforming of the case, or does this shell need to be full length sized everytime?
 

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htran said:
In a case like this, would this be considered appropriate fireforming of the case, or does this shell need to be full length sized everytime?
I think Nate is right on the money, I get the same marks (maybe not as severe) on my .338LM with mild or heavy loads without any primer issues or ejector marks. Be carfull when you bump the shoulder not to exceed .002" Max. I suggest F/L sizing each time. I am on my 6th cycle of my .338 Lapua brass without issues. The softer the brass to more prevalent this becomes Federal,Norma,Nosler for example.
Sully
 

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I cannot tell from the camera-work whether the chamber diameter is excessive, but all of the cases comming out of my Remmy have that characteristic.

There is no overriding need to FLresize the cases. Indeed, I leave mine the way they are (neck only) until the shoulder needs bumped and I'm getting 30+ reload cycles on my brass.

Might be fun to measure the point of maximal expansion with a 4 digit micrometer!
 

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Discussion Starter · #12 ·
First! Sorry for the long delay, I had to go out and shoot another 3. These were out of my Yugo M76, while the orginal post was out of a Yugo M48 Mauser. On the vertically aligned trio, the top cartridge has such a loose primer it will fall out if turned bottom down. I measured a case from the M48 which would represent the highere end of what I didn't toss out for the the size of the ring. It's diameter was .4705"; is this the correct measurement? The load was 49.5gr of Varget, which worked fine in my remington brass, so i didn't think it would be a problem with the Winchester. Woops.. :/ I also was wondering do you guys scrub out the chamber with solvent so it's dry before you shoot? I don't and was wondering if it had any effect.
Lastly: Almost all of the cases that i deemed acceptable from that fired batch were unable to snuggly hold a bullet after full length resizing. Am i gonna have to buy a crimp dye or did the cases just expand beyond their reloading capabilities?


 

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These cases look like too much pressure: ejector wipe, blown primer pockets.

Tell us about the load. And tell us about the condition of the two guns.
 

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I'll not mince words: Good GOD almighty! You are WAY too far into the powder can dumping!

Back OFF no less than 10%!

MitchAlsup said:
These cases look like too much pressure: ejector wipe, blown primer pockets.
And craters, and anvil popping, and primer migration, and...

-Nate
 

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WOW, Stop! Just Stop and pull all that you have loaded (do you have a bullet puller?). If you keep that up you won't be posting much longer!! Go get you a book on reloading and read it! Then read it again.
Sully
 

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natdscott said:
Back OFF no less than 10%!
To add to what Nate just said, unless this is a Mauser action manufactured in the last 2 decades, you are currently lucky to be alive. The metalurgy used in the WWII stuff won't take modern pressure levels.
 

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Discussion Starter · #17 ·
(MitchAlsun)
M76- Brand new green mountain chrome lined barrel. Seems sturdy, all the parts look new and the only wear marks are the ones that i gave it. Whenever I shoot it; it has a nice harmonic buzz that lasts a second or two. Almost all my load development has been geared toward this rifle.


Yugo M48- My first rifle :) I bought this from Mitchell's Mausers about 5 years ago. It was the grade below mint condition. The bore and barrel are prestine and the rifling is sharp and ungrazed. I refinished the stock a few weeks ago so it wasn't orginally this glossy. Forgive me; i'm young and I like them shiny. From the research that I have done for this rifle. The Yugoslavian M48 Mausers are some of the best and most sturdly built. The M48 was the post WW2, forged from all new parts in Yugoslavia. Unlike the M24/47's which are captured and frankensteined with miss matched parts. But still fine pieces in my opinion.


That last pic took alot of camera and light blocking to work.

My load compilation for the 8mm so far has been (ALL YUGOM76 except where noted)
45gr Varget, 180gr Nosler ETip,Remington Brass and Primers: 2527,2538,2512
The above load wasn't stout enough to fully cycle the action in the M76.
47.5gr Varget- Cartridge OAL was too long for the action to fully close.
48.0gr Varget, 180gr Nosler Etip, RBrass,Rprimer: 2565,2555,2577,2594,2605,2593,2583,2603,2606,2606. Listed in sequence of being fired, and worked reliably.
48.6gr Varget 200gr SMK, remy brass and primers: 2605
49.0gr Varget 200gr SMK rbrass,rprimer: 2579,2579,2586,2581-
This setup worked excelletly.
(YugoM48-bolt action) 50.0gr Varget 200grSMK, rbrass,rprimer, 2647
52gr Varget, 180grNoslerEtip, winchester brass, cci large rifle primers. 2871,2815,2854
base of brass was fine, but the buldgy ring around the case was pretty big.
~49.6gr Varget, 200grSMK, winchester brass, cci primers. No velocity but the above pics should serve well.
I would like to point out that all these velocity numbers were taken with the chrony 10 feet away on a 3 foot tall shotgun trap. I was fireing upright, unsupported, and in an akward semi crouch.

No worries! I don't have any of those lying around. I loaded up 10 round with IMR4350 and started at 48gr which is the starting load in my nosler table.
Thanks guys! I really appreciate your help.
No i don't have a bullet puller :(
 

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natdscott said:
I'll not mince words: Good GOD almighty! You are WAY too far into the powder can dumping!

Back OFF no less than 10%!

MitchAlsup said:
These cases look like too much pressure: ejector wipe, blown primer pockets.
And craters, and anvil popping, and primer migration, and...

-Nate
Haha I just love that entire post Nate! Good luck klopinger, be safe.
 

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WOW, Stop! Just Stop and pull all that you have loaded (do you have a bullet puller?). If you keep that up you won't be posting much longer!! Go get you a book on reloading and read it! Then read it again.
^^^^^^^^^^^^^ This
Then if you don't understand something in the book or books ASK BEFORE YOU GO ANY FURTHER! :shock: :shock: :shock:
 

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Discussion Starter · #20 ·
That's why I'm here :)
1. Is it better to shoot with an oiled or dry chamber?
2. How loose is too loose with a seated bullet. I was only able to salvage 6 of the 50 winchester cassings from that last batch. On 4 of them the bullet is able to rotate when a mild amount of force is applied. I haven't tried to pull them out. They were full length resized.


Yeah my Sierra manual was a little lacking in the section covering the signs of overpressure. I will back down for sure. However these cases are by no means the majority, most fall victim to being smashed into the barrel face because of a FTE. My main goal for that rifle is to have it feeding and ejecting reliably, and then brass condition. Fixed the feeding problem, and i'm starting off with 49gr IMR4350 in the next batch, I'll probably go up and below and below in .25 increments and see what it likes the most. From my experience with the Varget this veloicty range seems to be the optimal zone.
 
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