7mm RM splitting necks 2 firings

[JLM8401]

I can see the crease in Brass from the picture. Had the same thing happen with Winchester 22-250 brass. Any piece of brass that had small vertical lines at the neck shoulder junction would split the neck on 2nd firing. I don't know if the brass is too soft or it's just thin in this area because of manufacturing issues. The brass shouldn't be creased ever

I didn't have any luck sending it to Winchester. So now i buy Lapua.

 

[GLTaylor]

Had same problem. Got back into annealing at least every 3rd loading. No more problems

 

[Buckreed]

Thanks everyone for your responses. I'm thinking I'll buy some higher quality brass and start learning to anneal.

 

[Canhunter35]

Plenty of people will recommend 'better ways to consistently anneal' but take a propane torch, an impact wrench and a socket to fit brass into an slowly rotate outside the cone of the flame and watch as it changes colour down the neck and shoulder, and ur splitting neck problem will go away. Good luck

 

[Buckreed]

Plenty of people will recommend 'better ways to consistently anneal' but take a propane torch, an impact wrench and a socket to fit brass into an slowly rotate outside the cone of the flame and watch as it changes colour down the neck and shoulder, and ur splitting neck problem will go away. Good luck

Thanks. I'll try this tonight.

 

[okie man]

I had the same issue with my Hornady 6.5 creed brass. Took the expander out of die and sized a case. My die was sizing my necks way too much. That with hard necks to begin with resulted in split necks when fired in cold temps. Sent the die with 5 fired cases to rcbs but are sitting on a shelf from the corona virus. I did order a lee collet neck die and played with it a bit and that may be the best $30 I've spent on sizing dies

 

[Buckreed]

I had the same issue with my Hornady 6.5 creed brass. Took the expander out of die and sized a case. My die was sizing my necks way too much. That with hard necks to begin with resulted in split necks when fired in cold temps. Sent the die with 5 fired cases to rcbs but are sitting on a shelf from the corona virus. I did order a lee collet neck die and played with it a bit and that may be the best $30 I've spent on sizing dies

Interesting. I started by neck sizing and had some issues with reloads chambering tight due to the headspace being set off the belt. I spun the barrel off and head spaced off a once fired brass. No issues. Then I decided to try full length sizing for a while. No issues there either until this. There has been a lot of helpful information here. And I think my answer is a combination of quality brass, annealing, and possibly neck sizing.

 

[bigedp51]

Chambers and dies vary in size, look at the cart at the bottom, the RCBS .223 dies varied .005 in neck diameter. And I have had two new bags of Winchester .243 brass with cases that had split necks and shoulders. I agree with the other posters who said try another brand of brass.



Are Your Sizing Dies Overworking Your Rifle Brass?
http://www.massreloading.com/dies_overworking_brass.html

Table 2 - Inside Diameter Measurements for 5 different sizing dies

 

[chev4x4s1975]

I would try adg brass excellent brass

 

[Jack C Patterson]

That is within the limits and should be ok.

Many ammo manufactures stopped annealing there cases during the ammo crunch and have not returned to this step. I recommend annealing all factory loaded ammo after the first firing or buy new cases with annealing heat marks.

Case brass comes from the mill annealed for forming the cases. this process work hardens the brass and it needs to be annealed again before or after polishing. years ago, we liked to get our brass shiny, so they polished it as the final step. now they just polish it and don't do the second anneal very necessary for case life.

I look for this sign that it has been annealed or anneal it my self. this is just one brand that it is very obvious.

Prvi Partizan Ammo 300 Winchester Mag 165 Grain Pointed Soft Point

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J E CUSTOM

Had the same issue with Hornady brass, after annealing, problem solved. Have since moved to Lapua and Norma brass

 

[dakewlndn]

I have been loading my Savage 116 7mm Rem Mag. I have been running Rem Brass (at the time mainly for consistency, cuz that was the type of brass I had a larger amount of, had a few Winchester brass but never tried it). I got about 8 to 10 firings before I start to see case head separation indicators. Had a split neck on 4 cases from a lot of 50 I was rotating somewhere around the 5th or 6th firing.

I did slowly upgrade my reloading process.
I started annealing with the good ol socket/drill method but after getting the split necks, I bought a Benchsource but I wasn't a big fan so sold it and saved up for an AMP.
Dont get me wrong, the socket method got me by for years and it worked. But I wanted consistency so I ended at the AMP. I highly recommend it for those who can afford it. I couldn't for a long time as well.
I SS tumble, WFT trim, Neck Size with a Redding, Sinclair Expand and seat with a Redding.
150 Noslers ABLR running 3250 lit by H4350
Tried 26, 22, H1000 & a few other but my rilfle likes H4350 with single digit SD's and 2.75" at 400
But took half (or more) of my stock barrel life to find that. Soon I will have to look for an upgrade in the barrel dept and start the process all over.
Tip that worked for me during the socket method is to try and do less time than more. Use some Templaq to help you get your time in the flame down more consistently.