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Turboman
03-06-2011, 08:07 PM
Just curious does anyone turn down their black powder cases?Ive got some 45 basic brass that id love to use in my shiloh with grease groove bullets,But with the chamber I have it just wont fit, Chambers to tight,I need to turn down the brass 3000 for it to work,Whats your thoughts on it?Im already using .458 bullets,The brass is just to thick once ya seat the bullets the case is just to big to go in the chamber.
jeff

montana_charlie
03-06-2011, 10:16 PM
Put that brass away for the time when you want to try paper patching.
Buy a batch of Starline cases to use for grease grooved bullets.
CM

kokomokid
03-09-2011, 09:37 AM
I neck turn 40/65 cases down to .010 thick due to haveing a tight chamber and it is a pita. My 40 has a neck .500 long but I dont know how much this would help on a taper case. Did learn that most brass has lots of thich and thin places on the neck.

texasmac
03-19-2011, 12:53 AM
Kokomokid,
Is your 40 cal a Browning BPCR? The reason I asked is I also outside turn the Remington case necks to 0.010" for my Browning .40-65, which has a well defined neck that is .5" long. I believe it's a definite benefit to uniform & consistent neck tension and uniform bullet release.

Turboman,
In my mind, one of the factors in deciding to turn or not to turn depends on the chamber design.

In a chamber with a well-defined neck (ID the same throughout the length of the neck) if the case neck is not turned to a consistent thickness the forward portion of the bullet will be gripped with less tension than the rear portion of the bullet.

In a typical chamber without a well defined neck, the chamber taper is similar to the taper of the case wall thickness. In other words, the case taper compensates for the chamber taper, generally resulting in a uniform ID, at least in the forward region of the case, and a uniform grip on the bullet. If the front portion of the case is outside turned to a constant thickness, when the cartridge is fired the front will expand (fire form) to the chamber taper, resulting in a tapered ID of the forward portion of the case and a non-uniform grip on the bullet. So the bottom line is I don't believe there is a benefit in neck turning in this type of situation and it may actually be a detriment to accuracy. A good example is the Browning .45-70 BPCR chamber, which does not have a well defined neck.

Now, with all that said, if the bullet diameter is too large for the chamber and maximum case dimensions, then turning the case walls may be an acceptable solution. Give it a try and see how the accuracy holds up, but if I were in your situation I'd follow CM's advice.

Wayne

kokomokid
03-19-2011, 08:34 AM
My gun was an early build for the BPCR. I talked to one of the guys that built these guns at the last match and he said the barrel is a tapered KP stainless -oven blacked. They got a reamer cut for 40/65 and it had to be reground, that is reason for the tight neck. The action is a browning 78 with a tang welded on and a baldwin base built into tang. Shoots beter than I can. IT just dont do chickens well.

nicholst55
04-02-2011, 11:24 PM
FWIW, Sinclair makes a neck turner specifically for large caliber rifle cartridges, although they don't offer a .45 pilot as a standard item. You'll have to have them make you a one-off pilot for your .45 BPCR cartridges if you need one. I checked with them, and they will make them.