ADI Brass Headspace Issues

[mchughcb]

I need some reloading advice.

I recently bought some once fired ADI brass in 308Win. I loaded up 50 rounds for the Blaser BD14 after I full length resized. Today at the range I had about 5 from 15 that failed to fire. The CCI large rifle primer was struck but not very hard. The ones that fired were struck and the primers looked liked moderate pressure.

When I got home I finally got to use my Hornady headspace tool. Using my once fired brass I zeroed one and checked the other fired brass and it was all zero. I then checked the rounds that didn't fire and they were consistently measuring 13-14 thousands of an inch. I then pulled my hornady brass which I've reloaded and checked against the once fired ADI brass and the reading was either 2 or 3 thousands of an inch. This got me thinking that the 14 thousands of an inch is just that little too far for the firing pin to consistently fire the rounds.

I then pulled a batch of 4 from 390 I've just FLS and they are all 14 thousands of an inch compared to the fired brass.

Any suggestions about what can be done because it looks like the shoulder has been bumped too far?

Also I noticed there was about 3 cases that fired but was hard to open up the action. One round really had to break it over my knee to open it. But only 42.5gr of 2206H it not near max nor are the primers flattened.

[Vaughan]

What is the volume of a fired ADI case vs the fired Hornady brass? I was just wondering if the ADI brass was especially thick. Doesn't seem likely but a thought.....

[mchughcb]

I'll need to check

[Vaughan]

Still don't see why the ADI brass would have resized 12 thou shorter than the Hornady, seems like too much for the brass to "spring back" (or not in the case of the ADI brass) after being pressed in the die.

If you have checked a bunch of the FL resized ADI brass and they are all the same length at 12 thou short, then for it to be so consistent you would think it was something mechanical with your die/press/shell holder setup. Run a few Hornadys through and check?

Frustrating when stuff like this happens....

As for what to do with the short brass. Either shoot it when it doesn't matter or pull and dump. But dumping wouldnt solve the problem for the rest of the brass and If it is 390 cases, that is a lot to dump..... Do you have a different 308bbl like an R8? Might fit/shoot better...

[dchamp]

I’m not sure what is going on but I would first check headspace on both ADI and Hornady fired and non resized brass. I would also back off your sizing die and then start by adjusting your die slowly until you reach the deiminsion you want. I would also check case weight. Another item to consider is checking your primers and primer pockets. If your primer pockets are a little to deep or the primer is a little small, then it may be a simple solution of using a different primer. But that is something you would need to measure.

Here is a Saami spec for the .308win. Notice that it is indicationg using a .400” headspace gage and is showing 1.634-.007”. Your headspace may not be that exactly but should be close to those parameters. Good Luck

308win saami.pdf

[mchughcb]

Set the hornady headspace unit up to measure absolute headspace on the fired brass they were 1.634, 1.632, 1.634" after firing.

I then measure the ones that didn't fire and they were 1.620 to 1.621".

I then measured two that were fired and resized and they were 1.621"

I didn't think it was possible if you full length resize by making contact with the shell case holder that you could bump the shoulder back to more than the saami spec. Was never an issue with the hornady brass. They all just fired.

Not sure what to do now as I've done a few hundred and they are all sitting around 1.620" so it will be hit and miss if they fire.

[slugslinger]

This is a tricky one. I too thought that FL dies should prevent resizing beyond SAAMI spec. A few years back, when I started measuring head to datum very carefully after resizing brass, I found out that you can indeed push the shoulder way too far by setting your press to "cam over" . . . but it never occurred to me that it could go beyond SAAMI spec.
Unfortunately, it appears you would have to fireform the brass back to a reasonable shoulder dimension, and obviously some won't fire. Engineering and fabricating a (temporary) slightly longer firing pin for the rifle seems risky (and expensive). You may just have to abandon some tbd number of "won't fire" (albeit expensive) ADI brass, which is unfortunate.

Regards,

[dchamp]

I don’t know. I wouldn’t think that .006-.007” below minimum would cause that condition, but that appears to be the case.

Before going crazy I would try and fire some of those problem cartridges in another gun. If that didn’t work I think I would check primers and primer pockets. I wonder, if you take one of those cases that didn’t fire, pull it apart, pop the primer and then try a different brand primer or even a magnum primer and see what happens.

[9.3x64]

Some dies will resize to saami spec without touching the shell holder, and that’s how I prefer it. Several of my dies have had appointments with a grinder if they do touch the shell holder.
If it were me mate I would try a different primer as suggested by dchamp above. But if that doesn’t work , I would not be firing them in my BD14. Get new brass and back that die out.

[analog_peninsula]

Good luck with the investigation. Its amazing how many times dies aren’t quite what they seem.

[Vaughan]

But if I read the OP correctly, the dies resized Hornady brass just fine at the same settings, so it is not just the die over sizing when screwed down to touch the shell holder, which would not be a shocker... Maybe I got that wrong.

[SPEEDY]

Did you measure any of the brass that hadn't been resized yet? The problem could be with the original brass.

[deerhunter338mag]

Did you measure any of the brass that hadn't been resized yet? The problem could be with the original brass.

My thoughts exactly after reading all that. Different chambers, do different things

[mchughcb]

Did you measure any of the brass that hadn't been resized yet? The problem could be with the original brass.

Unfortunately I just setup and resized 400 in one go.

I have a few ideas. My first is I've pulled the ones that I had and by luck my mate gave me several hundred winchester LR primers. Talking to a gunsmith this week he said that CCI is hard and the winchester and remington are softer. I've pulled the ones that didn't fire and loaded up about 20 of them. I'll see if they all go off with a softer primer.

On the ones that did go off I've gone back to the die and backed it off. After a bit of trial and error I managed to get it set that it was 0.003" compared to the fired brass after FLS and it fits easily in the BD14. I've loaded them up with the CCI primers. Tomorrow I'll test them. If they all go off then the ones that were bumped too much I will load with the winchester LR and finish loading them. If the FLS sized brass goes off with the CCI then I'll use them going forward on all the brass that has been fired and bumped back 0.003".

As a complete back up I've bought another 300 once fired Hornady brass so if all else fails I'll fall back to that.

Will report outcome later.

[mchughcb]

Well I have no idea. The first part of the plan worked okay and I was able to get the rounds to fire and accurate. However all rounds were almost impossible to extract. With break open lever to the right I had to break the rifle over the knee to get it open. Pressure doesn't look that high.

Just waiting for the Hornady replacement brass next week and hopefully I can go back to how it used to shoot and extract.