Poochy Primers

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.
 
F Guffey, did you miss the part about the concave bolt face?
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Primer is still protruding above flush, right? Brass still sooty?
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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.

F. Guffey
 
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.

F. Guffey
 
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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Ok... Why could it not happen to me? Also what constitutes sooty? Any discoloration?
 
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!
 
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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.
 
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.
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I have upset case heads .010" meaning the case head shortened from the top of the cup above the web to the case head .010" and then it turns into one of those things a reloader can do nothing about; at the same time the case head shortened and increased in diameter. If the bolt face was concaved when fired the case would have trouble standing up straight. A North Texas shooter hammered a case head so hard the smith that dug the case out of the chamber could not read the head stamp.

And then there were all of those sweaters, they were making wild guesses about how long the bullet was when it left the barrel. The North Texas shooter purchased 308 W ammo for a 25/06 chamber, that would be for a rifle he did not own.

F. Guffey
 
The center of the bolt face being .005 to .006 deep does account for part of the primer pooching out. I had three primers leak a while back and they did go a bit too easy when pressing them in. Each time left a little hole in the bolt face. I ordered a spring too. The gun smith i had brought it to before discounted the need for a spring as well as that the bolt face is concave. I did called about getting a bolt kit and firing pin spring. I don't think he wants any more work.
 
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The center of the bolt face being .005 to .006 deep does account for part of the primer pooching out. I had three primers leak a while back and they did go a bit too easy when pressing them in. Each time left a little hole in the bolt face. I ordered a spring too. The gun smith i had brought it to before discounted the need for a spring as well as that the bolt face is concave. I did called about getting a bolt kit and firing pin spring. I don't think he wants any more work.
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It would have helped had you started with the whole story. I got suspicious when you came out with "BINGO! We have a winner.

F. Guffey
 
Yosemite Steve said:
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!
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Ya probably already herd about this. Don't start 10% under the starting load! Start 10% under the max load.
 
Did you think i knew that and was holding back?
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I do not know what your knew when you knew it. as Don Fisher suggested reduced laods are cute but there was a member that feed his 257 Wieatherby a steady diet of reduced load and then? Suddenly and without warning his rifle swarmed on him. There was not one bent piece of metal, there were nothing but straight line fractures.

Everyone but me decided it 'must have been a double charge'.

F. Guffey
 
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