Lee Collet dies
If you are shooting one rifle of a particular calibre, then they work fine, as long as that rifle is not one that is known for having a springy action or for stretching cases upon firing. However, I do use them for the .303 British, but keep the loads a bit milder for target use only. Also, if you have several rifles in the same calibre, then you WILL have to keep your brass segregated.
Lee Collet Dies neck size only. For cartridges that go back into the same rifle, that is not too much of a problem. However, they do not full length resize, so if your buddy gives you some once fired brass, it will probably not fit in your rifle, unless it is full length resized first.
As for accuracy, the Lee Collet dies are very good. So good in fact that Lee offers a money back guarantee if you find a set of dies that will load more accurate ammunition.
Part of the accuracy comes from the fact that YOUR once fired brass is now a very close fit in the chamber of YOUR rifle. The Collet Dies will neck size the brass to hold the bullet, but your cartridge case more or less centers itself in the chamber of your rifle. Full length sized brass takes the cartridge back to minimum dimensions, and therefore there is more looseness around the cartridge in the chamber, especially if you have a chamber that is close to maximum dimensions.
The Lee Collet dies are a good addition to a reloading set up, but are an addition and you should also have a full length resizing die on hand too.
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