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Old September 25, 2012, 01:33 PM   #12
Mike Irwin
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Join Date: April 13, 2000
Location: Northern Virginia
Posts: 35,229
"You guys understand that ALL Winchester magnum cases are belted and that includes the .300WM which by the way is the most popular big hunting cartages not to mention the preferred sniping round of the US military."

Yes, I do, and I've always considered that to be a huge annoyance on Winchester's part.

I also know that belted cartridges they're more annoying to deal with when reloading, especially repeated loadings, and they are, GENERALLY, more difficult to bring to precise accuracy.

One of the biggest issues that I find with reloading them is the tendency for the brass to flow back to form a bulge ahead of the shoulder if one needs to full-length size.

The belt served a distinct function 115 years ago when the British introduced it -- as a means of getting precise head space control without a rim and near flawless feeding through a magazine.

The could have done the same with using a sharper shoulder and no belt, but there were a couple of issues with that directly related to the cordite propellant.

First, cordite had to be loaded in the case while it was still straight walled, THEN the case was shouldered and necked. Because of the amount of space taken up by cordite, long, shallow shoulders were preferred, otherwise the cordite could form a compressed plug at the shoulder and lead to a combination of erratic performance and pressure spikes.

Second, because cordite could also be very techy in very hot climates like India and Africa, it allowed gunmakers to cut a generous chamber around the neck and shoulder, which did a good job of helping control pressure spikes from hot cartridges.

Today, though, belts aren't necessary and I greatly prefer the ease of not having to deal with them.



Oh, and regarding the "preferred sniping round of the US military.... Not quite true.

The Army and Marine Corps use several rounds for sniping, including the .308/7.62x51, the .338 Lapua Magnum, and the .50 BMG.

So, US forces use three non belted cartridges for sniping purposes and one belted cartridge.
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