Originally Posted by tomme boy
That whole statement is wrong.....
That whole statement is wrong.....
"As long as there's lead in the air....there's still hope.."
Well I wanted to give him a chance to clarify it before I went that far. I digress, yours may have been the right approach.
The Dunning-Kruger effect is alive and well.
How so???
The anvil is spaced out a little farther, have a harder to ignite compound and the cup is harder on the #34 LR military primers. If the firing pin is not sticking out far enough as in on the low side of protrusion. Then with a chamber that is on the high side of the HS. And brass that is sized back too far then you a high tolerance stacking problem. Adjusting the protrusion to the high side could help with the tolerance stacking.
As to the spring being shorter they do lose compression over time. So yes the firing pine spring will probably be shorter.
Oh and by the way, I am still waiting on your response from a rifle you built that the bedding was cracked and the barrel was not free floated like I paid you to do. Only been about 8 years or more. Still waiting on a response. Or a refund.
The anvil is not spaced out farther, it's shorter. I has to be because the cup is thicker. All primers have the same tolerance in height. CCI uses the same compound in the 450's as they do in the 41's. The firing pin will not penetrate any primer more than .025", no matter what the cup thickness, anvil height or spring pressure. In my studies of ignition, the penetration of firing pin dent averaged .021" over 18 different primers, using stock springs.
In an ideal situation where there is no headspace, setting the protrusion to .025" would be sufficient, however when you figure in some shoulder set back of .002", it might be wiser to increase the protrusion to a minimum of .030",which would give you more than enough reach for full detonation.This would be for precision handloaders who have control of what they load for their gun. For the average varmint hunter, .035" will cover the gammet. If it won't fire at that length, you don't have enough spring, or enough travel, or you have enough headspace it won't reach. For that matter, be glad it didn't go off. As far as the headspace being long from the factory...not bloody likely. They are checked several times by several different workers. It is far more likely that the shoulder of the case was set back too far.
In this case of the Axis, the firing pin is one piece and cannot be adjusted like the standard 110 pin. The standard FP protrusion is .055", and the only way to "adjust" it is to shorten the tip. At .055" protrusion, the travel to the primer is reduced by the amount of difference it takes to get a .025" penetration. In other words, you are losing about .030" in travel, which translates into lost momentum. That short amount doesn't sound like much, but it is equivalent to 7 in/oz in impact energy.
Springs do NOT lose compression over time, they lose compression over cycles. High volume production compression springs as used for firing pins are made from "Rocket wire", not the common garden variety music wire used in common hardware applications. These types of springs are not suitable for repeated rapid cycles, and will take a set and continue to lose compression.
Because firing pin springs are made in high volume, they are not "conditioned". To properly condition a compression spring, it is first stretched 1% per coil over it's free length, them compressed to solid height. The result makes it slightly shorter, relieves some stress and puts it into it's compression range....kinda like stretching a ballon before you blow it up.
That last line....I have no knowledge of, nor do I know who I'm dealing with.
"As long as there's lead in the air....there's still hope.."
Well said Fred!!
Oz never gave nothing to the Tin Man, that he didn't already have.
Your wrong FRED. CCI states the anvil is spaced farther away on the 41 primers.
Tomme, I am interested in this. I went to CCI's site but the only thing I could find was that they are built to Military spec's. Can you provide a link. Thanks
I did Find this in a technical article however;
CCI/Speer Technical Services says: "The CCI 400 primer does have a thinner cup bottom than CCI 450, #41 or BR4 primers... [with] the CCI #41 primer... there is more 'distance' between the tip of the anvil and the bottom of the cup."
Credit to John Barsness "A primer on Primers"
The Dunning-Kruger effect is alive and well.
You know what?? It is no longer on their site. It used to be. And it gave the difference of the depths as well.
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