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Old October 9, 2002, 10:57 PM   #1
tex_n_cal
Senior Member
 
Join Date: July 14, 2002
Location: North Carolina!
Posts: 308
In praise of "Coke Bottles"...

...in other words, straight pistol cases that fit the bullets so tightly the case is visibly swollen where the bullet is seated.

There is another thread running where someone discussed how they disliked this look, and considered it a flaw in the dies, to size a case so small.

Some years ago Scovill showed in Handloader a chart where the expander plug in the #2 die was progressively made smaller, tightening bullet fit. The case in question was the .45 LC. As he reduced the size of the expander, tightening bullet fit, velocities grew more uniform. Increasing the tightness of the roll crimp did not suffice to replace a tight fit of the bullet in the case.

In my straight walled pistol cases, I have turned down the expanders so about all they do is bell the case mouth, prior to bullet seating. It has proven quite successful for me in the .44 mag, .45 acp. .357, 9mm, 10mm, and .40 S&W.

In autoloading pistols, a tight bullet fit becomes even more vital - if the bullet is driven back into the case during feeding, pressures can rise rapidly. I have a hunch that many of the problems reported with .40 S&W handloads in Glocks are a result of the bullet getting shoved back in the case when feeding. If the bullets don't have a channellure for crimping it becomes even more critical to have a tight bullet fit.

Things get really nerve racking with an extra short-bottlenecked autoloader case, like the .400 Cor-Bon (which I have loaded) or the .357 Sig (a future project). These cases have only the shortest neck available for holding the bullet. It proved extremely difficult to get bullets to stay put in the .400CB, though I did eventually manage it. I found that a small expander, a severe taper crimp, and tumbling the cases after sizing to remove all trace of lube did the trick.

Factory .400 CB's have bullets with channellures - the bullets can actually be pushed into the case, but the case mouth catches on the edge of the channellure and stops the bullet from going any deeper.

Your bullets must fit tightly for reliable handloads.
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With top loads & hard cast bullets, a .357 mag, .41 mag, .44 special, .44 mag, .45 Colt, .454 Casull, .475 Linebaugh, .480 Ruger, .500 Linebaugh Maximum, and .500 S&W will all shoot through Bison. To select the gun, determine how big a hole you want to put in the Bison, and how much recoil you can stand
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