Generally how many shots do you get from your brass

[CMoor]

This is one of my Hornaday cases after the first reloading. 123 gr ELDM with 27 grains of A2520. I did 20 rounds and only one ruptured like this.
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[Klem]

CMoor,

Unusual, given it's a mild load.

Do you know why this happened?

[LR1955]

My die set is made by Hornady. Not really a big fan of Hornady dies but this set seems pretty good for both my rifles chambers. My 6AR dies are LEE 6 ARC dies and they also seem spot on for my chamber.

RT3:

I have noted on the Forum that the guys who use the Hornady die set are always super happy with its quality and performance. When I got the custom dies and then the Redding dies, Hornady was still a couple years out of making Grendel dies. When the Hornady dies hit the market, guys seemed really pleased with them.

LR-55

[603Country]

I have a neck split problem with my Grendel. The barrel is Ballistics Advantage and is a good shooter. Something I mentioned on the forum a while back was that once fired Hornady brass, on the first reload, split on 49 of the 50 reloads. Splits and even shattered necks. It had to be the brass. I bought some Starline brass, thinking that would fix the problem. I’m not having splits as bad as I did on the Hornady, but splits after the second reload on a more than normal percentage of the cases. Maybe, I thought, it was the chamber. I got out the micrometer and started measuring. Here’s what I got:

- bullet diameter .264
- Loaded round case neck OD of .290
- case neck OD after firing of .299 to .300
- resized case neck OD of .287

From poking around the internet, those numbers look normal. If so, do I just have another batch of bad brass? I had heard you guys say that grendel brass has a long life, but I’m not seeing that. Neck tension of .003 seems reasonable.

What am I missing? This is a Redding FL sizing. Used maybe 150 times so far.

[Klem]

Those measurements look normal, although on the generous side. My expansion from sized to bullet release is 0.008. Yours is .013".

SAAMI Grendel chamber neck spec is listed as .300 so yours is on the limit, but acceptable. My spent cases are .2940 so that is from a tighter chamber (Lilja).

Could it be lube? Are you lubing the necks?

Your resized brass is a result of the expander ball widening it back out again to OD 0.287", as it gets dragged out. If you take out the sizer stem/expander ball what does the neck get squeezed down to? I have removed the expander ball in the Forster and the sized OD is 2.860". Have lost count of the number of reloads but maybe 10+ (Lapua cases).

[LR1955]

603 and Klem:

Given all of his measurements seem close enough, let me offer that looks like a very tight chamber that is not allowing the brass to expand when fired.

Could be something else too but this is a potential cause.

Not sure a headspace problem would cause this without blown primers.

LR-55

[603Country]

Klem, I have the press set up, but forgot to do the resize without the expander ball. After I finish fixing downed fence this morning, I’ll get that measurement.

As for the case necks, I brush them out before resizing, and the brush has a small amount of RCBS lube on it.

LR1955, I was thinking my chamber was a bit loose, but you say it looks tight. Could you expand (pun intended) on that please.

[Klem]

603,

I have a Redding FL sizer too. I don't use it however as it squeezes the neck to much, and when the expander ball is dragged back out it expands the neck too much. The cases end up with an OD of .2895-.2900". As we know the OD of a loaded bullet is .2900-.2905, so that means the bullet grip is only .0005. Fine for a bolt gun, but not a lot for an auto-loader.
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If your sizer is squeezing the neck the same as my Redding to .2780 (no stem), and after seating and fired expands to .300, that is a lot of stretch. But the splits could be from an unsupported neck at time of firing.

55,
If 603 measures his spent cases at .300 then that is plenty of room in the chamber to release the bullet. But...if his Redding is like mine and only holds the bullet by .0005 of neck tension then the bullet is able to move when slammed into a semi auto and comes to a sudden stop. The bullet moves forward with inertia and jams into the lands. As we know with throat jammed bullets there is a spike in pressure at firing. With 603's generous .300 chamber the case at the neck is unsupported at the time of the pressure spike. The unsupported necks split. If the case neck is properly expanded and sealed/supported against the chamber wall then there is no reason for the split.

The Forster without the expander ball squeezes the case neck to .286. The bullet goes in and it is now .290 = .004 of neck grip. That's why I prefer the Forster to Redding - it works the brass less, and grips the bullet more.

[603Country]

Ok, here’s the squeeze data. I took a shiny neck fired case and resized it without the expander ball. It went from 0.30 fired to 0.280 resized. And with the exp ball, the case neck gets opened up to 0.287.

From what you guys have said, it seems that my Redding FL sizing die is sizing a bit too much and the exp ball is working it too much (back to 0.287). Further, my barrel chamber might be a bit ‘looser’ than ideal.

Unless you say otherwise, I need a bushing die. What’s the latest and best? I have a Redding bushing die for the 223, but I’m not married to Redding. And I can sure enough get another barrel if need be.

bottom line…what’s the best way to get me to long brass life? Bushing Die, or Bushing Die and new barrel.

and, just to mention it, I called Ballistic Advantage yesterday morning to discuss the problem. They said they would discuss it in-house and call me back. Haven’t heard from them so far. Maybe they will eventually call, but I don’t suppose it matters much. The barrel appears to be in spec, so they’ve done nothing wrong.

[603Country]

Just ordered a Redding Type S FL Bushing Die and bushings of .285, .286, and .287. We’ll see how that works to reduce neck splits. Next step, if necessary, would be a new barrel and a conversation with the barrel maker on chamber neck size.

[Klem]

603,

I don't have an issue with Redding either, and use their dies for other calibres. It does however seem that my Redding die, purchased some years ago, works brass differently to yours. Your squeeze is less severe than my Redding, and your expander ball leaves it with a .003" grip. That all sounds perfect, which makes me think it is the barrel.

I use a Redding bushing die for a 6.5x47L bolt gun and it does a good job. I use the .288 insert which gives .002 grip.

My thought about your necks being unsupported and the reason for the splitting still stands. Because if the necks have expanded hard up against the wall of the chamber (like they are supposed to) then the pressure takes the next easiest path and that is pushing the bullet down the bore (as it is supposed to). If pushing the bullet is too much resistance at the time then it will go the next easiest path and break off a bolt lug. If the pressure is being shared at the neck between the brass hard up against the thick wall of the barrel (as it is supposed to), and the thick steel of the barrel, then there's no reason for the brass to split - I mean, where does the gas go? Or in other words, if the brass has split when hard up against the chamber wall then it would be because the barrel has split too, and that of course is a catastrophic breach like a grenade.

You wrote that spent cases measure up to .300 which is right at the max of SAAMI specs for the Grendel. If we add a little more for brass springback, that means the chamber is actually larger than spec. The whole idea of using brass is that it is elastic. It expands to seal, but then contracts so it can be extracted. Spent cases have fireformed to the chamber but then contract slightly, meaning when fired they were maybe .001 more against the wall of the chamber.

Another thought is that if your chamber neck has been reamed too short then on loading the case mouth gets crushed into the bullet, preventing bullet release. The rest of the neck is unsupported and in that case it splits. The mouth getting crushed and gripping the bullet more often happens with hand-loaders letting their cases creep forward without trimming. The Grendel is very forgiving for case creep however and I rarely, if ever need to trim cases. I am thinking this scenario might be because of an out-of-spec chamber then; either too wide or too short. And because even if the load is hot it shouldn't split necks - more likely chip a bolt lug.

I am leaning to the necks being unsupported at the time of firing. If new brass is splitting at the neck on first firing then what sizing die you have is not the issue, and won't fix it. It's not headspace either because that splits the case down the body at the web.

[603Country]

Klem, you make a lot of sense, and it has long been obvious that you know what you are talking about. But before I get a new barrel, which is tempting, I’ll try the new die out. Probably will load 5 new cases, shoot them, repeat until the necks split. If I get only 2 or 3 uses, a new barrel will be added. If I can get 5 or more, than I’ll be happy. I have a 100 yard range just outside my barn workshop, so this will be a fairly quick test.

[LR1955]

Klem, I have the press set up, but forgot to do the resize without the expander ball. After I finish fixing downed fence this morning, I’ll get that measurement.

As for the case necks, I brush them out before resizing, and the brush has a small amount of RCBS lube on it.

LR1955, I was thinking my chamber was a bit loose, but you say it looks tight. Could you expand (pun intended) on that please.

603C:

Klem explained it in a later post. We aren't sure what the issue is but that sort of split looks to me like the neck is getting crushed a bit when it chambers and is not allowing the brass to expand and release the bullet effectively. Results are splits like I see in the picture. The middle to shoulder is split and normally you would see the entire neck split open. Short chambered like Clem says. The front part of the neck is being pinched on to the bullet when chambered and when fired, the pressure build up behind the bullet ruptures the lower part of the neck. Again, not positive but a oversize chamber normally lets you get a number of shots before the neck splits.

Load a dummy, measure the front of the neck, load it and extract it then measure the front of the neck again to see if the front of the neck is being squeezed down on to the bullet by the chamber. Again, maybe and maybe not but my best guess without knowing anything else about it.

LR-55

[603Country]

I’ll do it in the morning.

[Klem]

603,

That sounds like a plan.

If you've ordered another FL die then all good, makes sense to see if that makes a difference. To clarify, your current Redding die sounds fine, it's mine that works the brass more than I prefer. My Forster with the expander ball removed is the best of all three specs however.

As for whether the splits are coming from a short chamber neck, here's something that might interest. I picked up a neck length gauge a while back. It's a machined plug that interference fits into a deliberately shortened neck. You pull the plug out proud and then load it into the breech. As it goes into battery the chamber's neck pushes the plug in to its dimension. Then you carefully extract it to measure. The one in the picture is for .223.
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I read somewhere of a hack where you can do something similar with a bullet loaded short into a hacksawed neck. Then file the off-cut neck ring thinner and slide that onto the bullet. When loaded into battery it does the same thing as the gauge above - pushes the ring further onto the bullet. Gently unload and measure base-to-ring. Never tried it however so can't comment further.

It's one thing to hope your barrel has been machined within specs, but another to actually know.

[603Country]

I tried LR1955’s suggestion. Did it 3 times with different rounds, and even put marks-a-lot around the leading edge of the case. Measured before and after and can not see any difference in OD that might be caused by a short chamber crimping the case neck. And no scuffing of the marks-a-lot. Cases are all trimmed to 1.510”.

Next, I’ll try the cut-off neck approach.

[603Country]

Just finished trying the Klem method. Took some work with a Dremel and a hacksaw. The chamber measured at 1.52, and all cases are trimmed to 1.51”, so it seems the chamber is within spec, though maybe the chamber neck is a bit looser in diameter than necessary, at 0.300 (assuming no spring back). Now I wait on the delivery of the new dies.

Thanks to Klem and LR1955 for the test suggestions.

[Klem]

603,

Unless there is a void in the shoulder/neck of the chamber, caused by a chip of metal breaking off then the chamber sounds generous but within spec.

Turning to the ammo - What about shooting some factory ammo? As you say, before going the nuclear option and swapping out the barrel a pack of factory ammo would eliminate everything associated with hand-loading (dies, bad powder batch, bullets shifting into the lands on being loaded etc).

[603Country]

Klem, the factory ammo was where the problem raised its ugly head. I bought a bunch of Hornady factory 123 gr SSTs and paid way too much. The idea was that I’d have plenty of brass for reload purposes, so that justified the overpayment. When I had 50 empty cases, I reloaded them (no annealing at that point). The cases, 49 out of 50, split at the necks and sometimes split where the case neck joins the case body. Worse splits I had ever seen. I just put it down to bad Hornady brass and bought some Starline and Lapua. And here we are. Something isn’t right. If the bushing dies don’t fix the problem, I’ll be asking you guys for advice on a new barrel. I’d want a light barrel with excellent accuracy.

All the other Hornady fired brass has been annealed and bagged for later testing.

[Klem]

603,

OK, it's not the ammo then. I doubt that new die will do anything if factory ammo is splitting. And if the bullets are not being pinched (neck length fine) then it's looking like too much clearance around the shoulder neck area. And/or the bullet is jamming in the lands because of the throat.

Factory ammo, multiple brands of cases, mild load, you obviously know how to hand-load - got to be the chamber.

Here's a thought, that chamber might still be more than .300 if when the split occurs the gas escapes, pressure equalizes and drops inside/outside, and the case stops expanding. I read that in some large chambered old guns hand-loaders sometimes use two lots of firings to fully fire-form their cases, by using mild loads. So one mild firing expands it half the way, and the second fully fire forms it. If they used a full single load from the start it would split the case. Also, sloppy machining of chambers in cheap barrels is to be almost expected. It makes sense it's more likely a simple reason rather than something more exotic like a die from a reputable manufacturer ('Occam's razor').