Remove white from lead tips on bullets

B said:
I shot some Dominion .22 a few years ago. The box and cases were pristine aside from a deeper copper color to the cases than I'm used to. Many split/cracked or pinholed and would spray an appreciable and annoying amount of gas and debris as they did so. So I guess the "worst" could be a case failure which can certainly damage your gun and yourself.
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As brass corrodes it looses its zinc, old tarnished or oxidized copper coloured brass is sure sign of that

https://www.canada.ca/en/conservati...rrodes, it can,brass and even its perforation.

“Preventing and Treating the Dezincification of Brass – Canadian Conservation Institute (CCI) Notes 9/13
List of abbreviations
Introduction
When brass corrodes, it can undergo dezincification, a process in which zinc is lost and copper is left behind. Mild dezincification may simply cause a cosmetic change, namely, the colour of the surface turning from yellow to pink, but severe dezincification can lead to the weakening of brass and even its perforation. This Note explains what dezincification is and where it can be encountered in conservation as well as how to prevent and treat it. The Note also describes a demonstration of mild dezincification.“

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Perfect example of it
 
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^ I should have looked closer, those are Dominion cartridges. Aside from the bullets and packaging being pristine my cases were the same color. I guess it was a thing with that ammo as I have shot plenty of old and older .22 than that '60s or so stuff. Great post, thanks!
 
I Dont Care About You said:
THIS is why the COAL dimension is totally worthless. You need to measure to the ogive and then seat bullets at least .010" back from the lands.
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I have measured the ogive. I didn't give this data as it would be meaningless to anyone here as its absolute value depends on the bullet shape and point of measurement on the ogive. Mine are seated to a consistent 3.250 for what it is worth. I'm going to re-seat them deeper as I'm concerned about them just touching the lands at that length.

It is however common to see COL quoted in reloading manuals. I don't consider it worthless, as the cartridge has to fit the magazine. Loaded to maximum allowable COL may not come even close to touching the lands with spitzer bullets.
 
Grizzlypeg said:
... Loaded to maximum allowable COL may not come even close to touching the lands with spitzer bullets.
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That, I think, can be a back and forth thing - I think was how Roy Weatherby kept his Max pressures down on some of his early boomers - a long "jump" (free bore) to the lands. I will tend to get mixed up between loading for max accuracy (target rifle) versus loading for hunting (absolute minimal effort to load from mag and to chamber). I've never done it, but I think some target shooters are okay with a "snug" to close bolt - if it gets them the perfect results - I can not imagine tolerating that on my hunting loads - I do miss and want the next round to come up and chamber just like "snick" "snick".

I suspect there are standardized lengths - otherwise how could factories load and produce ammo to sell? But when I am hand loading for my rifle, I tend to fuss to find the lands, and then to load a specific amount away from them. Even scarier, a bench rest shooter acquaintance advises that the land surfaces get burned out from firing rounds during the barrel's life - and you "chase the lands" by loading longer and longer to maintain the accuracy level that you are looking for - and you re-find and re-measure that most every time that you load up a batch for that rifle - so most of us want that exercise to be relatively quick and painless to do.

As per a previous post that I did on CGN about "jump" - I have a number of 30-06 rifles - albeit most made prior to 1960 - using COAL given in Nosler manual, on two of them I would have adequate "jump" clearance, but on another one I would be signficantly into the lands at that COAL using their bullet - so is NOT how I load - all are 30-06, but each gets its own load.

https://www.canadiangunnutz.com/forum/showthread.php/2230590-A-cautionary-tale
 
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legi0n said:
Erik Cortina does not like chasing the lands because whatever jump you set up, it will increase with every shot you fire.
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Think about what you wrote - if you start with 0.020" jump and the thing wears to 0.040" jump, that makes no difference? If that is true, then why bother about it at all - and that guy has won some trophies for sure ...
 
legi0n said:
Erik Cortina does not like chasing the lands because whatever jump you set up, it will increase with every shot you fire.
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I believe he advocates finding the node and setting the bullet seating to the minimum jump that works in the node, so that as the jump increases owing to throat wear, it makes no difference until it breaks outside the node.
 
I ended up seating them 0.020 back from the lands, at a COAL of 2.690. I got my best groups at 42.0 and 43.0 grains Benchmark, both under an inch. 41 grains and less was really bad. Two inches plus.
Good enough for some bulk bullets I bought for cheap.
 
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