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Old May 9, 2018, 10:37 AM   #26
Metal god
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My first thought was the reloaded rounds being the problem as well . Maybe a small base die is being used ??? How ever I can see factory new ammo not showing a problem when fired but the second time the problem shows it's teeth . If the chamber is right at max Sammy spec and the factory and reloaded cases are at the minimum AND this is a hot load . I can see getting one firing but not a second do to excessive working of the case .

The larger head diameter does concern me though . As we all know the case does not get sized all the way to the extractor grove , really not even close because the brass is so thick down there it does not need sizing because it does not expand enough to stay stretched out . So if that area is growing in diameter there is a problem for sure and the primer pockets should be blown/stretched out as well . If the primer pockets are still tight and hold primers ?? Then I think we don't have the full story or I'm not understanding fully what's happening .
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Old May 9, 2018, 11:00 AM   #27
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There might be a head space problem. Should be easy fix if it is. Use your FL die and neck size, don't size all the way to the shoulder. Use a once fired case. See if the starting separate head still does it there. If not I'd say head spce and just correct it with partial loading. That ring around the case head. You sure it's a separation starting and not just the die stopping there? Head space in a case like a 30-06 is not common. reason being, e on the shoulder.chamber's are cut for the cartridge to headspace on the shoulder. with belted nd rimmed cse's it's more common as they do not headspace on the shoulder but rather either the belt or the rim, some chamber's are a bit sloppy but the fix is partial sizing to move the shoulder in a position to pretty much headspace on it.
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Old May 9, 2018, 12:40 PM   #28
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A number of people are giving advice on how to size/partial size your cases to "fit" the chamber. And its generally good advice, IF your problem is what THEY THINK it is.

From what I'm reading, your real problem isn't what they think it is (case/chamber length issues) and every dimensional fit problem isn't "headspace".

As I see it, based on what you say (and assuming your measurements and terms are correct), your problem is due to excess chamber DIAMETER (girth, NOT length).

Why aren't factory loads failing, when fired the first time???
The answer to that one is simple. (and something well known to anyone who has reloaded the .303 British for SMLE rifles).

The chamber is "too big around" (at the head, .003" expansion of a factory load is too much). The brass stretches, ALMOST to the failure point, but not quite TO that point, on the first firing.

The brass is "overstreched" (again its diameter we're talking about not case length, or distance to the shoulder datum line (headpsance), these things do matter, and can result in similar early case failure, but at this point its the oversize diameter that, I think, is the most important factor.)

You size it back down (some, in a standard die) but then since it has been worked so much, already, the case fails when it is again fired in the oversize chamber.

Headspace (measured for the .30-06) could be spot on, but if your chamber is oversize in diameter (again the .003" head expansion) your case life will be very short. One firing. That's what you are getting, based on what you're telling us.

Again, I'll mention the .303 British and SMLE rifles. The rimmed .303 Brit case headpaces on the rim. Headspace in that rifle is the space where the rim fits. And ONLY the space where the rim fits. That one dimension can be perfectly within tolerance, and the rest of the chamber can be almost ANYTHING, and the gun will pass a headspace check. But the oversize chamber means the case has to stretch too much to have a long case life.

And, it doesn't matter, to the designers, or military users. As long as each case fired ONCE without rupture, its "good".

Your rifle MAY be the same thing, only in .30-06. Chamber length to the datum line (headspace as measured for that round) might be fine, or good enough, but its the OTHER dimensions of the chamber that are causing your issues.

Diameter issues cannot be fixed by neck sizing the brass. Length issues can be, sometimes, but too large a chamber diameter cannot be.

Get a good chamber cast done on your rifle. Carefully check the area of the case head for diameter. It may be oversize, and out of spec. It may be right on the outer edge of the spec tolerance range. If its out of spec, Remington made it wrong. If its right on the outer edge of the tolerance, despite the issues, its not "wrong".

No gun maker is under any compulsion to make their guns "reloader friendly". Most are, and that's why we reload, but some are less friendly by intent, and others by result.

A new barrel with its new chamber probably will solve your brass life problem, but be aware that a new barrel essentially make it a new rifle, and you'll have a new set of quirks to learn to deal with.

If your rifle put every shot in the same hole, every time, but cases only lasted one firing, I'd accept that, for the accuracy you get. If it shoots like a normal rifle, then I'd look into getting the barrel "fixed" or replaced.

Good Luck
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Old May 9, 2018, 03:16 PM   #29
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I think I said all that? So if I agree am I agreeing with myself?

A new barrel done right will not have any issues. It would be hard to do worse that whats been done

Criterion or Shilen from Norther Shoots Supply is a good choice.
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Old May 9, 2018, 05:45 PM   #30
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AMP 44 and RC20 I believe have hit the nail on the head.
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Old May 9, 2018, 06:15 PM   #31
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UM, not to put too fine a point on it...

But YOUR cases don't get resized all the way to the extractor groove.
Mine get resized from rim to shoulder since I use a case roller BEFORE sizing die that sets the shoulder so the Datum point/line comes up right on specification.

Not only does the rim get resized, but the rim gets straightened, the groove gets straightened/spaced, and the lower case bloat gets pushed back where it belongs with a case roller.

As for the OP,
Keep in mind it's been very recently that 'Tight' chambers made it into the mainstream.
My Rem 700 in .30-06 came with a super sloppy chamber.
I bought it cheap because the previous owner said the thin barrel 'Wouldn't Shoot!'
The rifle probably didn't have two boxes of factory ammo run through it...

I measured the brass, measured the chamber and promptly pulled the barrel.
Cut 3 extra threads on the barrel, recut the chamber with a PROPER size chamber reamer.
Setting the barrel back just a few thousands allows you to rechamber WITHOUT a new barrel or extensive (expensive) work.


Keep in mind the reamer or barrel had to be WOBBLING when the chamber was cut.
This is consistent with the way Remington finish reamed chambers, with a hand drill motor & long shank reamer.

Now, if you go this route, while the barrel is out of the receiver...
1. Square face cut the receiver! Remington does NOT lathe cut receiver stock tubing.
The front face is RARELY square with the bore of the tubing.

2. Recut/Straighten the receiver threads.
Threads are cut on a 'Hogging' machine with a tap, not lathe cut straight with the bore of the receiver.

These two steps are cheap/simple to do to the receiver and straightens the receiver/barrel connection.

3. Have about 3-4 EXTRA threads cut into the barrel.
Barrel threads sometimes need to be straightened, but this is automatic when the threads are cut on a lathe.

4. SQUARE (not radius!) the face of the barrel where it hits the receiver!
A radius will keep the the barrel from mating to the recoil lug square/flush.

This is an EXCELLENT time to install a bigger recoil lug.
A thicker/longer recoil lug will serve you better, particularly if you intend to epoxy bed the action into the stock.

Now, you simply trial fit the the receiver to the barrel/recoil lug, taking off of the back of the barrel (Chamber Mouth) enough so the bolt closes.

When the bolt closes easily, then you use headspace gauges and finish ream until the headspace gauges say you are good to go.

Now you have Remington's custom shop action for $500 less...
For about $500 Remington's custom shop will correct the issues they screwed up in the first place.
Takes about 2 hours of (actual) gunsmith time.
(Idiots with a hammer & vice aren't gunsmiths)

I turn receiver first, then center/turn barrel so I can screw the receiver on/off while I'm fitting the barrel & rechamber it. You only have to chuck/center each part once that way.

It will take longer, but any jobber machine shop can do this work also.
It's simply setting the barrel back, shaving the excess from barrel produced by setback, and finish ream to desired chamberings.
(and/or polish if you are feeling froggy. I polish simply because the barrel is still in the lathe and it takes an extra 10 minutes, super easy, and a crowning touch on the job)

A actual gunsmith will own a thread cutting lathe that has a through head so the barrel can protrude through while working in the chamber.
Most all Jobber shops will have a thread cutting lathe, but they *Might* not have a through head, but most will.

Since this is the 'Smithy' forum, I spelled it out in detail...

When I try to tell people that selling the rifle & buying a new one won't change the crappy way manufacturers do things, they don't get it.
When the gunsmith is well trained & equipped, this isn't a big issue to fix.

It's also why so many people complain about 'Bloating', and it's why reloaders get fits trying to resize a lot of brass...
It's a gold mine for the makers of the 'special'' dies that correct some of the issues crap chambers produce in the brass!
A case roller starts about $1,200 and it doesn't save the brass from the damage being done, just corrects the damage the chamber created.
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Old May 10, 2018, 03:14 PM   #32
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JH: While all true, if you have to pay for that work , what is the cost? Most machine shops would not touch it as they have not experience let alone liability involved.

Pull the barrel, sell it as is with note it needs work due to over sized chamber. It would give a gun smith who can do the work a low cost blank? I would not sell it as a good barrel.

That said, the Remage is an easy aspect. Maybe $150 max for barrel removal and install the new one as no work needed.

New barrel about $350. And you get to pick your profile. Bull to thin.

On the other hand a new Gun is ? If I wanted a good shooting gun the Remage is the low cost way to go. Not sure I would true up the action but you can throw it in the mix and see how the costs play out.

Only heavier barrel 30-06 out there is a Remington, and its a long throat for ELD bullets and long range shooting.
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Old May 11, 2018, 04:13 PM   #33
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Bad chamber, cut oversize, out-of-round.
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Old May 15, 2018, 08:41 AM   #34
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Quote:
I definitely agree with Mobuck. I would use some virgin brass & fire-form some cases to headspace properly to your rifle.
I wouldn't, I would find some cases that have been fired in an old trashy chamber that was too long from the shoulder of the case to the case head. I would find those cases with the Hornady/Sinclair case comparator or a Wilson case gage and or a home made model of a take off barrel or a new barrel; and then there are gages that can be used differently. My favorite case is a case that will not allow the bolt to close, there are times I have to use 280 Remington cases formed to 30/06 to determine the length of a long 30/06 chamber.

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Old May 15, 2018, 08:52 AM   #35
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It's also why so many people complain about 'Bloating', and it's why reloaders get fits trying to resize a lot of brass...
It's a gold mine for the makers of the 'special'' dies that correct some of the issues crap chambers produce in the brass!
A case roller starts about $1,200 and it doesn't save the brass from the damage being done, just corrects the damage the chamber created.
I have a Winchester Model 70 chambered to 300 Winchester Mag, I asked Winchester to send me a set of their dies to match their chamber or a rifle with a chamber to match my dies.

I took the rifle to their warranty man in the area, I explained to him the chamber was too long from the shoulder of the chamber to the bolt face and I informed him the chamber was too large in diameter. He said he would hone, polish or ream the chamber and I had to ask; which one of those cures makes the chamber smaller. Anyhow I went back to check on the rifle and by that time the rifle was sent back to Winchester. And I ask why? The warrant man said the chamber w3as too long from the shoulder of the chamber to the bolt face and the chamber was too large in diameter. And then I asked how it got that way, was it when he polished the chamber, or when he honed the chamber or when he reamed it??? And he said it came in that way

I need to take the rifle to the range, they returned it 15 years ago, I loaded 100 rounds for the rifle and then changed my mind.

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Old May 15, 2018, 05:41 PM   #36
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A actual gunsmith will own a thread cutting lathe that has a through head so the barrel can protrude through while working in the chamber.
Bullhockey.
Plenty of smiths (myself included) cut perfectly fine chambers between centers, both by choice (Speed) or necessity due to a spindle bore that's either too long, or too small diameter to work through the headstock.

Tell McMillan, Kelbly's, and many others they're doing it "wrong"....
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Old May 15, 2018, 08:28 PM   #37
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JWilson904,

It seems like the trouble only happens with your handloads. Would you mind giving us the load details (case, primer, specific bullet, COL and powder and its charge weight)? Have you tried intentionally loading down about 10% to see if it still occurs? If so, as suggested by Mobuck, something is happening to the cases. If not, the load is likely too hot in addition to the chamber possible being wide at the breech (can happen if the reamer went in off-center and was not properly floating). Do you have some photos of the cases after firing to share?
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Old May 16, 2018, 01:01 PM   #38
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Bloating: ?

Quote:
It's also why so many people complain about 'Bloating', and it's why reloaders get fits trying to resize a lot of brass...
It's a gold mine for the makers of the 'special'' dies that correct some of the issues crap chambers produce in the brass!
A case roller starts about $1,200 and it doesn't save the brass from the damage being done, just corrects the damage the chamber created.
Again, a smith/reloader built a bunch of rifles with wildcat chambers. That created a demand for cases that did not exist before he made the rifles available. He called and ask for help; I did a Jerry Clowers/Marsalis thing, first I had to determine if the cases could be formed .

It took more dies than I thought it would but there were no failures in the forming process. He had 460 belted cases that were as long or longer than the 300 Win Mag. case; problem he had 40 cases that would not fit the #4 RCBS shell holder and there was no way to stuff the 40 cases into a forming and or sizing die. The cases had increased in diameter ahead of the belt by as much as .014" and the case heads had expanded .012" in the extractor groove. The 40 cases had been loaded too heavy, the case heads expanded and shortened etc. I suggested he not use the cases but I explained to him we could use a collet in one of his lathes to reduce the diameter of the case head and case body ahead of the belt etc.. He decided not to use the cases with the pounded case heads.

He did ask how the case expanded ahead of the belt; I explained to him he would not believe and or understand the answer.

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Old May 27, 2018, 07:32 AM   #39
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Gunsmith says the chamber is fine. He says my loads are too hot! Going to start over with imr 4350.
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Old May 27, 2018, 07:40 AM   #40
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Quote:
Originally Posted by UncleNick
Would you mind giving us the load details ?
Please.... I'm having a really hard time with multiple/repeated case separations from
overloads w/o having any warning signs like sticky bolt opening, brass-flow ejector marks,
primers falling out, enlarged flashholes, etc, etc...

Details on what your gunsmith calls "too hot" would really be helpful.
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Old May 27, 2018, 10:41 AM   #41
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50 grains of AA 4046 over 165 grain accubond. Set close to the lands and very accurate load. I don't have any pressure sighns exept flattened primers either. There just inst much info on AA 4064 OAL 3.353. Some how I missed Uncle Nicks post asking.

Last edited by Jwilson904; May 27, 2018 at 11:32 AM.
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Old May 27, 2018, 10:49 AM   #42
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I am with Mehavey.

Your load may be mildly hot - that should not begin to take out top quality brass in 2 firings or less.

AA4064 is close but not over the limit ( 8/10 less) with a 165 Nossler Partition and its 2.3 grains less for an all copper Barnes.
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Old May 27, 2018, 11:01 AM   #43
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50 grains of AA over 165 grain accubond
"AA" ?
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Old May 27, 2018, 11:06 AM   #44
Jwilson904
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BTW: What is the fired case length vs unfired/new Norma brass ?

2.481 before 2.483 after
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Old May 27, 2018, 11:09 AM   #45
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4064
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Old May 27, 2018, 01:51 PM   #46
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Barring a dramatic Lot# problem.....
and using Default 68gr H2O case capacity:

30-06/165NosAccubond/AA4064/50gr
barely makes 51,000psi in a 60ksi cartridge
+10% BurnRate --> 61,000

w/ Nosler case: 72gr
46,000 psi (+10% BurnRate --> 55,000psi

Barring gross blunder on somebody's/manufacturer's part, the OP isn't even close to overpressure.
Far from it.

JWilson:
- Get yourself a Headspace Comparator
- Size a once-fired case to where the bolt will juuuuuust close on it
- Measure the headspace dimension/subtract 0.002" --> Write It Down
- Size all future cases to that dimension
- Let us know....
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Old May 27, 2018, 05:01 PM   #47
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(Edit)

What/how did the smith check out the rifle?
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Old May 27, 2018, 06:43 PM   #48
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Checked head space with go and no go gauge and measures my fired brass.
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Old May 28, 2018, 12:58 PM   #49
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Mehavey,

You must have missed, way back in his second post, that the OP said his case heads were coming out +0.003" wider in diameter than before firing. That's a very strong pressure sign, which is why I asked about the load and suggested reducing it.

In his description of the load, he says the bullet is very close to the lands. Many people think you actually have to contact the lands to get the pressure increase associated with such contact, but you don't. Dr. Lloyd Brownell's study of pressure in the 60's showed that, beyond a minimus, pressure rises in an s-curve shape that approaches the contact pressure continuously and is almost there just before contact is actually made. This can cause anywhere from about 20% to 30% increase in the pressure rise in some guns and bullet and powder combinations, as compared to having some normal jump, and that's what I suspect happened here. A load that should be 61,000 psi with jump could get up into the proof range, and be 73,000 to 79,000 psi.
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Old May 28, 2018, 01:17 PM   #50
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I made 3 rounds yesterday with 55 grains of imr 4350 reduced the OAL AND I still see the cracks with brand new norma brass although they are less noticable. Accuracy was terrible at 100 yards. Nice rounded Winchester primers.
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