light loads tough on brass???

19 June 2006, 07:57

I have been making up some light loads for 100 grain bullets in a .270 Win using SR4759 according to the Speer manual. I like the light recoil and reasonable accuracy--especially for teaching my young son. However, i am becoming very worried that in a batch of the last 50, I have had visible splits in the neck of cases which have been reloaded only 3 times. And this is with start loads, not max.

Do these loads stress the case more than loads with slower burning powders? Or was this just an anomoly? Thanks for any help out there.

I get no stress signs or neck damage with max loads of 4350 and 4831 ( H or IMR ). ...I never go over the never exceed values for any load either.

19 June 2006, 08:10

vapodog

I've noticed (what I think is) short case life due to split necks using nickel plated cases.....are your cases nickel?

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19 June 2006, 16:12

jgnfld

No. And the other funny thing, as I said, is that max loads w/ 140 gr. bullets from the same batch of brass are not showing this sympton at all.

Maybe I should go with the Youth Loads that Hodgdons supplies on their website using H4895.

19 June 2006, 16:42

vapodog

quote:
Maybe I should go with the Youth Loads that Hodgdons supplies on their website using H4895.

A couple points
1. light loads don't necessarily mean light pressures.....I'm sure Hot Core will chime in here...

2. I'm sure you know....split necks should be discarded but is not at all unsafe to the shooter

Yes.....try the Hodgdon loads to see if that helps.....it would be great if you'd report back...this is interesting.

19 June 2006, 19:35

bbell

In my 270s I have been using the 100 gr remington bulk bullet , 44 gr 3031, win case, win std lr primer. Yields 2700 fps, very little kick abd the brass lasts forever. Kicks less than a 243. I hope this is useful to you.

19 June 2006, 20:26

akalinin

quote:
Originally posted by jgnfld:
I have been making up some light loads for 100 grain bullets in a .270 Win using SR4759 according to the Speer manual. I like the light recoil and reasonable accuracy--especially for teaching my young son. However, i am becoming very worried that in a batch of the last 50, I have had visible splits in the neck of cases which have been reloaded only 3 times. And this is with start loads, not max.

Do these loads stress the case more than loads with slower burning powders? Or was this just an anomoly? Thanks for any help out there.

I get no stress signs or neck damage with max loads of 4350 and 4831 ( H or IMR ). ...I never go over the never exceed values for any load either.

I've been using 18gr of SR4759 with a 100gr 30 cal Hornady semi-jacketed lead bullet. Brass = Lake City 69. This combo is amazingly accurate in my old Madsen, and fun as hell to shoot.

I have had no neck splits, but cases are only on 2nd reload. I'll have to watch for this.....

20 June 2006, 16:19

Hot Core

quote:
Originally posted by jgnfld:
...Do these loads stress the case more than loads with slower burning powders? Or was this just an anomoly? ...

Hey jgnfld, Interesting questions. No doubt the dv/dt is totally different for the entire pressure cycle.

I've been thinking for a couple of days on this and can only remember having Split Necks in Reduced Loads used in Reformed Cases. Once I annealed them, the problem stopped.

But, I've not seen what you are experiencing in regular cases with Reduced Loads. I do agree with:

quote:
Originally posted by VapoDog:
...1. light loads don't necessarily mean light pressures ...

---

Any chance you might have gotten some type of Bore Cleaner, with Ammonia in it, on those Cases?

Are you Resizing them "differently" than the Full Power reloads?

20 June 2006, 18:08

Grumulkin

Another vote for annealing the brass; I doubt it has anything at all to do with high pressure.

20 June 2006, 18:34

jgnfld

Looking over my setup (this was the last batch I reloaded), I'm not entirely sure now that I had the sizing die adjusted correctly. At least right now it is set too deeply and so probably was then.

That may have been the problem more than anything.

21 June 2006, 15:11

DUK

I have observed some loose primer pockets with Blue Dot loads for the .338 WM and the 9,3x74 R. This so far has never happened with the regular loads, even though in theory and by QL calculation the working pressure must have been higher for the latter. This is also confirmed by the primer picture, no real pressure measured, though.

Could this be explaned by the "steepness" of the pressure curve".