My experience tells me that it is often the last round left loaded that causes the spring the most wear from just sitting.
A spring is meant to work within a certain range of compression. In many guns the last shell compresses the spring so much that if you let it sit that way long term is has a much greater impact than all the other shells prior.
Think about it. Measure the shell you are putting in (some can be slightly longer than officially depending on crimp), add up the length of them all and subtract that from your magazine tube. How much space is left over for the spring. Do you really think a spring that long should be that compressed?
Sometimes the spring gets so compressed it folds over itself or gets mashed sideways. So it is not even being stored compressed straight up and down as designed, but is slightly deformed with a load in a direction it was not designed for.
This issue is greater wth some barrel lengths and extension tubes that match the barrel length because some just barely let that last shell fit and so compress the spring more. While others have an extra inch or two giving a little more slack. After you load the last shell in, see how much you can push it down the tube with your finger. Assuming its not already smashed out of shape, that will tell you how much space it has to sit without being fully compressed or compressed beyond fully compressed. In some guns there is nothing. Compressing a spring 100% wears it a lot more than compressing it 90%
That is why I avoid the threads that say it is only the spring being worked that leads to wear, and not sitting loaded. Yes that is true if the spring is only being compressed within the ideal range. But often that last round takes them beyond that. I especially see this more in magazines designed for locations that limit capacity by law. Some of the 10 round magazines for California are designed so there is absolutely no possible way an 11th round could be smashed in there, even if the base plate was bowed and someone with mental issues insisted on crushing one in there. They accomplish this by making that 10th round barely fit in there with the spring so smashed it is deformed and crushed against the bottom of the magazine. The last round is so tight it has no slack at all and cant even be pushed down a little.
That is not the compression level a spring is intended to be at. Crushed at the bottom.
A spring is meant to work within a certain range of compression. In many guns the last shell compresses the spring so much that if you let it sit that way long term is has a much greater impact than all the other shells prior.
Think about it. Measure the shell you are putting in (some can be slightly longer than officially depending on crimp), add up the length of them all and subtract that from your magazine tube. How much space is left over for the spring. Do you really think a spring that long should be that compressed?
Sometimes the spring gets so compressed it folds over itself or gets mashed sideways. So it is not even being stored compressed straight up and down as designed, but is slightly deformed with a load in a direction it was not designed for.
This issue is greater wth some barrel lengths and extension tubes that match the barrel length because some just barely let that last shell fit and so compress the spring more. While others have an extra inch or two giving a little more slack. After you load the last shell in, see how much you can push it down the tube with your finger. Assuming its not already smashed out of shape, that will tell you how much space it has to sit without being fully compressed or compressed beyond fully compressed. In some guns there is nothing. Compressing a spring 100% wears it a lot more than compressing it 90%
That is why I avoid the threads that say it is only the spring being worked that leads to wear, and not sitting loaded. Yes that is true if the spring is only being compressed within the ideal range. But often that last round takes them beyond that. I especially see this more in magazines designed for locations that limit capacity by law. Some of the 10 round magazines for California are designed so there is absolutely no possible way an 11th round could be smashed in there, even if the base plate was bowed and someone with mental issues insisted on crushing one in there. They accomplish this by making that 10th round barely fit in there with the spring so smashed it is deformed and crushed against the bottom of the magazine. The last round is so tight it has no slack at all and cant even be pushed down a little.
That is not the compression level a spring is intended to be at. Crushed at the bottom.
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