Cracked necks in 6.5 x 55 brass.

[aprayinbear]

I need some help from you more experienced reloaders. I've recently started reloading for my "new to me" Swedish 6.5 x 55 model 96. She seems to shoot well with my reloads and I'm getting pretty good groups (a few 5 shot groups under 1" from 60 yards with open sights and my aging eyes.)

But.... tonight when I came home I took the 20 rounds I had fired today, tumbled them until they were shiny again and found 4 cases with cracked shoulder/necks after only 2 reloads (see attached photo).

I am shooting Winchester cases from rounds which I bought and fired for the brass. I'm reloading with 35 grains Varget and using 120 grain Matchkings. This is the starting recipe in my Lee Manual. Trying to get as much accuracy as I can (and hoping to get more life out of the brass) , I am neck sizing only with my Lee Collet die. I am also weighing every powder charge, trying to be as consistent as possible.

Am I missing something? I wanted to check in with some of you more experienced folks, before reloading again. By the way, I've never had any problem with the Winchester brass I use for my 7.62 x 54, but I only use reduced loads behind cast bullets for my Mosin.




please.... all thoughts welcome!

 

[Seanhagerty]

That doesnt look like a crack to me. That looks like a scratch from your dies. I would take your siziing dies apart and look to see if there isnt something there that would cause this.

BTW, I am a newb at reloading, so take this with a grain of salt.

Sean

 

[ranger335v]

Your necks have work hardened to the point of splitting. It's the normal failure and isn't due to anything in your sizer die.

Such splits are harmless from a safety perspective but it's also time to toss the whole batch and get new cases.

 

[aprayinbear]

See the light.

No Sean...... you can actually see the light through the crack. And there are no scratches after the brass drops from the die. These only occr after firing a reloaded round.

other thoughts?

 

[NCsmitty]

ranger335v has the answer. I would say that you have reloaded these cases a few times and in doing so the brass becomes brittle.
If you are capable of annealing the area that is cracking on the rest of your brass, you will lengthen the life of your brass.
I use the pan of water method, but you need to be vigilant and watch the color change. It's easy to over heat and make it too soft.

Here's a link to some information on annealing.

www.6mmbr.com/annealing.html



NCsmitty

 

[243winxb]

Some Fuji brass on the first firing did this in 30-06. Bad brass. Another cause is an oversize chamber. Take measurements of your fired brass compared to the drawings here. http://www.stevespages.com/page8d.htm If your brass measures larger, it a big chamber. But with you only collet neck sizing, seems a brass problem. I dont think annealing is the answer with only 2 firings and neck sizing only. But its worth a try if the factory win. brass is out of spec.

 

[243winxb]

Powder charge- Your at the starting load listed in Hodgdon data. On firing some brass will get shorter, this can give you slop as your brass fits the chamber. When you don't FLRS the cartridge headspacing stays short. Increase your powder charge. Keep in mind that lite loads may not fully expand the brass in the neck area. Check by putting a bullet in the fired case. If its snug, you have low pressure.

 

[bullseye308]

Did they all have those 2 splits the same distance apart? If so it might be something in the chamber.

 

[aprayinbear]

No.... some just have one crack, in fact one bullet has two cracks but they are on opposite sides of one another.

 

[Bwana John]

Work hardened from resizing cases fired in "generous" chamber, or brittle brass.

Ive got a 7mm Mauser that does this, in as little as 4 reloading using nickle plated brass, ~8 with regular brass.

RCBS will cut you a custom die just for your chamber if you ask and send them fired cases. I just dont use nickle cases in that rifle, and use all brass cases with more than 5 reloads for reduced load plinking ammo.

 

[918v]

All military chambers are "generous."

Looks like you have a crappy lot of brass. Get some Lapuas.

 

[243winxb]

http://www.leeprecision.com/cgi/faq/index.cgi Follow link , dies, then look at 3 topics on the collet die. Maybe there is something there, if using the collet incorrectly???

 

[aprayinbear]

Headspace?

A friend said he thinks my headspace is too large. Could that lead to this problem?

 

[243winxb]

Headspace?
A friend said he thinks my headspace is too large. Could that lead to this problem?

Headspace is not normally a problem when neck sizing with a collet die as the body is not touched. Your at the starting load listed in Hodgdon data. On firing some brass will get shorter, this can give you slop(Excess cartridge Headspace) as your brass fits the chamber. Here is a link to help you understand headspace. http://www.brownells.com/.aspx/lid=11470/guntechdetail/Gauging_Success___Minimum_Headspace_and_Maximum_COL Excess headspace will normally give you case head separations or sometimes in the middle of the body of the brass. You will first see a bright shiny thin line form before the case headseparation. See photo

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[Ol` Joe]

Work hardened from resizing cases fired in "generous" chamber, or brittle brass.

Ive got a 7mm Mauser that does this, in as little as 4 reloading using nickle plated brass, ~8 with regular brass.

RCBS will cut you a custom die just for your chamber if you ask and send them fired cases. I just dont use nickle cases in that rifle, and use all brass cases with more than 5 reloads for reduced load plinking ammo.

I think this has it pegged....

 

[918v]

Headspace is normally not a problem if you adjust your FL die correctly.

 

[Bwana John]

Headspace is normally not a problem if you adjust your FL die correctly.

This is not a headspace problem (lenght from case shoulder to base), it is a problem of a "generous" chamber diameter at the neck to accommodate dirty, different spec, military ammo and a brittle lot of brass.
It can be cured with a custom die.

 

[243winxb]

On firing, the brass expands till its stopped by the chamber. If the chamber is "generous" or to large, the brass splits. First photo is a wildcat being fireformed. 2nd is wrong ammo used in the firearm. Note that the annealed neck/shoulder area did not crack, but the untreated area did crack. The head /web area should NEVER be annealed. Annealing may help?

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[627PCFan]

On an off note, ditch the Winchester Swede brass. I ordered 200 cases, weights were all over the place, necks were different thicknesses and flashholes were rarely centered-

 

[Float Pilot]

1. US made brass for the 6.5x55mm is undersized.

2. Buy some Lapua Brass. It is the correct size and the neck/shoulders are annealed. They last much longer.

3. The 6.5x55 has a fairly roomy case and was made to burn slower burning powder with a nearly full case. Partial cases will not give you very good accuracy.

4. For a m/96 you can load to a COAL of 3.140 inch. I usually stick to 3.100 or just a little over.

5. With boat-tails make sure you have at least one caliber's worth of bullet bearing surface. (.264) holding the bullet in the case neck.

 

[41 Mag]

Had the exact same issue with my daughters 96. Stoke up the charge a bit like suggested, possibly even going to a bit slower powder like 4831, either will give you a bit more of a load.

I had to start annealing about every third load or toss the split cases. I am using a set of Hornady dies which I have set to only get about 2/3 of the neck and about a half inch of the base of the case. They last up to around 6-8 loads like this which is fine as we generally loose them before they get there when hunting.

You could get a chamber cast and have a sizing die made or simply start annealing, and go with one of the bushing type dies first to see if that would work for you. Ours would get about two loads and then not chamber due to the spring back in the bases. So I started using the above mentioned method and like I said I generally loose them before they go bad now.

Good luck with yours.

 

[Float Pilot]

Use a slower powder..

Here are some 6.5x55 primer experiments .

With 46.3 grains of H-1000, Lapua brass, a Sierra 140 grain HPBT Match King bullet, and all loaded to 3.100 inches. With a very slight roll crimp.
I fired 3 groups, of ten shots each and averaged them.

Federal 210 Match Primer.......... CG63....2,528 fps 0.90 inch group
................................................m/96...2,517 fps 0.60 inch group

CCI 34 Military Primer.............CG63..2,540 fps...1.0 inch group
............................................m/96..2,503 fps...1.5 inch group

Win, WLR primer....................CG63..2,579 fps....0.40 inch group ********* GOOD LOAD
............................................m/96..2,514 fps....1.0 inch group
ONLY 17 fps extreme spread on this load!

CCI-200 Primer.......................CG63...2,560 fps...3.0 inch group
..............................................m/96..2,535 fps...2.0 inch group

CCI-BR-2 Primer......................CG63...2,563 fps...1.1 inch group
..............................................m/96....2,547 fps...0.70 inch group
Only a 10 fps SD on this load!
Might have shot better but both rifles were dirty and I was in a hurry.

Here are a couple of pics with H-4831 loads. See the crimp experiment.

 

[aprayinbear]

Wow...I'm learning a lot!

Thanks for all the suggestions and info!

Here's what I've decided to try. First, I sorted through the remaining Winchester brass (when I had my reading glasses and very bright light) and I found five other cases with what might be the beginnings of shoulder/neck cracks. That leaves me with 11 good cases remaining. One thing I noticed was that these cases after shooting 2 times, were shorter then standard. So I full sized the remaining cases and trimmed to size. I also have a suspicion that there is a problem with my neck sizing die or the way I am using it. Next I tried my hand at annealing and was careful not to get the brass heated past a very pale red. I was careful to anneal only the neck and a portion of the shoulder. I wish had some temper sticks, but am not sure where to find them.

Next, I'll load as before and examine the brass after shooting. I hate to change the load because I am getting good results with 35 grains of Varget. (see target below.... 5 shot groups slightly under 1" at 60 yards with open sights and my old eyes.)



And finally, I'll buy some more dependable brass like Lapua. I'd also like to try some reduced loads with cast bullets for plinking and target shooting (that is what I do with my 7.62 x 54r and the brass lasts and lasts.)

I really like my rifle and want to keep shooting it, but #1 I want to be safe. Does this sound reasonable?

Thanks again for all you thoughts, tips and support!

 

[243winxb]

Yes, sounds reasonable. Let us know what happens. Nice group.