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Old January 7, 2018, 09:06 PM   #26
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How'd That happen?
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Old January 7, 2018, 09:09 PM   #27
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Sounds like you got better result near max. It is actually quite expected when using slow powder (I still think it is a bit too slow for 30-06, even with 180gr bullet). It doesn't burn consistently at low pressure.

Things in handloading are inter-related. It may not be easy to discuss one thing at a time. It is actually more confusing.

Primer is still protruding above flush, right? Brass still sooty? I would check head clearance with tape. You mentioned you located the sizing die setting for zero head clearance, and then went back in a few thousandths. How many thousandths and how did you set that?

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Old January 7, 2018, 09:19 PM   #28
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Quote:
Originally Posted by Yosemite Steve View Post
243Winxb wins! It was the bolt face!

the center of the bolt face is .0125 deepr than the edge of the face!

Thank you!
It doesn't sound kosher. 0.013" is quite a bit. So the brass head is not supported by the bolt face? How come the factory round doesn't have high primer? Does the brass head become convex?

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Old January 7, 2018, 09:35 PM   #29
Yosemite Steve
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It doesn't sound kosher. 0.013" is quite a bit. So the brass head is not supported by the bolt face? How come the factory round doesn't have high primer? Does the brass head become convex?
I'm not sure why it's concave. I measured it repeatedly it is .013 difference from the center of the face to the edge. This gun is 30 years old but I am at odds to why as I never shot it that much really. Couple boxes a year until I got serious in my 30's and probably shot 3 boxes a year. Then last year I put around 400 through it. Another 80 over the last week.

Soft metal?
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Old January 7, 2018, 09:44 PM   #30
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Now I'm getting .005". I must have been sticking the caliper rod in the firing pin hole. I edited my original measurement. Sorry!
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Old January 7, 2018, 09:56 PM   #31
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Now that I have searched for it I am finding that this is a common thing and they come from the factory with some concavity at least sometimes.
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Old January 7, 2018, 09:59 PM   #32
243winxb
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A 30 year old gun may benefit from a new firing pin spring.

Check firing pin protrusion. Its different between firearms. About .055" more or less.



If there is no gas leakage around the prime, i would not worry about it.

Last edited by 243winxb; January 7, 2018 at 10:12 PM.
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Old January 7, 2018, 10:11 PM   #33
Yosemite Steve
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A 30 year old gun may benefit from a new firing pin spring.

Check firing pin protrusion. Its different between firearms. About .055" more or less.

A guess, as i didnt see make & model of rifle.

If there is no gas leakage around the prime, i would not worry about it.
There isn't. And thank you! I can get a new one for $26. My lefty costs less for some reason. This is a Savage 110CL series J 30-06.
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Old January 7, 2018, 11:34 PM   #34
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The primers seem to stick out about the same no matter what load I'm firing and appear on some factory Federal ammo that was high velocity as well. The factory ammo primers protrude about .003-.005". Is this enough to be worried about?
If the primer protrudes the case head did not seat against the face of the bolt.

And then the smith checked the length of the chamber and declared it 'tight'? And I wonder why he could not measure the length of the chamber in thousandths, he could have said the chamber was to- gage length, or no go-gage length or field reject length. And then there is minimum length, minimum length would be a tight chamber.

And then there are short chambers, I measure them all in thousandths.

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Old January 7, 2018, 11:41 PM   #35
F. Guffey
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A 30 year old gun may benefit from a new firing pin spring.
The firing pin spring would have nothing to do with a protruding primer, it would have something to do with a hole in the primer. The primer conforms to the firing pin, when the spring does not have the ability to hold pressure, pressure inside the primer pushes the firing pin back. With little support from the spring a hole appears in the primer causing the hot high pressure metal cutting gas to cut the bolt face.

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Old January 8, 2018, 07:45 AM   #36
Yosemite Steve
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F Guffey, did you miss the part about the concave bolt face?
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Old January 8, 2018, 08:31 AM   #37
243winxb
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F. Guffey - The firing pin spring would have nothing to do with a protruding primer,
I agree.
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Old January 8, 2018, 08:52 AM   #38
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The gun shack had the bolt head but not the rest of the kit. I went ahead and ordered it for $30 with shipping.
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Old January 8, 2018, 10:09 AM   #39
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That will be interesting to hear about. One way to cross-check the bolt face is to decap a fired case and draw it gently over a piece of sandpaper that is sitting on something flat, like a bit of scrap plate glass, to see if it marks the brass high in the center or all on one side. A full pressure load usually forms the head to its surface, insofar as far as it can.

Note that a standard headspace gauge would perch close to the perimeter of the bolt face, so a concave bolt face could, in effect, have excessive headspace at the center but not at the perimeter so the reading could still be good.

Changing the firing pin spring may have no bearing on your main symptom, but both Bart B. and Hummer 70, both of whom have been U.S. Palma team shooters (and Hummer 70 is a twice past U.S. Palma champion), recommend changing mainsprings every half dozen years or so to eliminate weakening from taking a set. This improves ignition consistency and makes lock time shorter and barrel time more consistent. In turn, the latter factor makes it easier for the gun to keep a sweet spot load performing consistently. So if you have the bolt apart anyway, it's a cheap thing to do easily. Also, there is some evidence that cryo-treated springs don't take as much of a set as an untreated spring, if you want to try that route.
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Old January 8, 2018, 10:33 AM   #40
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Wow. Great advice! Thanks. Do you have any suggestions on the best places to order those parts?
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Old January 8, 2018, 10:35 AM   #41
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As you mention ignition, i have heard a few rounds click and then fire. Would that be it?
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Old January 8, 2018, 02:47 PM   #42
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Delayed ignition can be due to any of several things: An incompletely seated primer is the most common. A weak mainspring is second. Least likely are contaminated primers or powder going bad.

Wolff will undoubtedly have a mainspring for you. If you get one of their extra power springs, they have about 15% higher force.

I mention cryo-treating decreases the tendency to take a set, as I've seen reported in information from the racing and aircraft engine applications. Since posting that, I've read a study showing cryo treatment increased the fatigue life of springs. But in that test, the treated springs did not do significantly better about taking a set, contrary to the racing engine industry claims. The fact valves in an engine are hot could have affected the results. But the bottom line, for room temperature anyway, seems to be that this may not be worth it after all.

The mainspring spring and pin tunnels of bolts are often not especially smooth inside. The spring rubbing its sides against that will gradually cut into the surface stress, affecting its life. For this reason, I think it is worthwhile to treat the springs with Sprinco Plate+ Silver. This is a lightweight bonding lube. It takes a 72-hour soak to get it attached to the metal surface. It does reduce friction significantly in the experimenting I've done with it.
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Old January 8, 2018, 06:21 PM   #43
Yosemite Steve
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Sir, thank you once again!
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Old January 8, 2018, 06:22 PM   #44
F. Guffey
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F Guffey, did you miss the part about the concave bolt face?


Quote:
Primer is still protruding above flush, right? Brass still sooty?
Primers are protruding or is there such a thing a pooch primer?

Concave bolt face" I believe There are two of us that could put 300 bolt together and measure the face of the bolt on all of them without finding one that was concaved. But is we did I will bet you the case head would be convexed after firing a max load. It has something to do with the .7854 thing.

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Old January 8, 2018, 06:26 PM   #45
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I know it could not happen to you but sooty cases and low pressure and cases not conforming to the chamber when seating primers can be caused by worn out barrels.

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Old January 8, 2018, 06:43 PM   #46
Yosemite Steve
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I know it could not happen to you but sooty cases and low pressure and cases not conforming to the chamber when seating primers can be caused by worn out barrels.
Ok... Why could it not happen to me? Also what constitutes sooty? Any discoloration?
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Old January 8, 2018, 06:52 PM   #47
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And yes the cases are convexed. Maybe .0015 shorter at the edge of the case head.

the .7854 thing?
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Old January 8, 2018, 07:58 PM   #48
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I'm estimating that this gun has about 1800 rounds at most fired through it. The only time it has key holed was when I tried loading some ammo under starting load to try mag primers. I took the suggestion to start at 10% less for mag primers and applied it to a starting load. Close to MOA is good enough for me. But I will always try to make em better!

Last edited by Yosemite Steve; January 8, 2018 at 09:07 PM.
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Old January 9, 2018, 09:12 AM   #49
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How'd That happen?
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Old January 9, 2018, 12:59 PM   #50
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0.0015" convex case head by itself isn't much. I was hoping it would reflect something more consistent with how far your primers are protruding. It would be interesting to indicate your bolt face and get a map of it but it would just be for curiosity's sake and is not required if the replacement is on its way.
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