Bullet bumping

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Blind Hawg
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Bullet bumping

Post by Blind Hawg »

What equipment is required to increase a cast bullets diameter by bumping?
Archer
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Re: Bullet bumping

Post by Archer »

http://www.castpics.net/subsite2/HowTo/ ... bullet.pdf

http://castboolits.gunloads.com/showthr ... sizing-die

So the easy cheap method would be using a press with a sizing die and a mandrel that could be formed from a nut& bolt as described in the second link.

A few more notes:
https://www.assra.com/cgi-bin/yabb/YaBB ... 1491309909

https://forum.castbulletassoc.org/threa ... the-cheap/

Of course getting a mold that makes the diameter you are looking for or buying the correct size to start with is probably easier and might be more consistent.
runfiverun
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Re: Bullet bumping

Post by runfiverun »

a swage die setup will do it easy enough.
but I'd rather lap the mold out if I only need another .001-2.
it's a very easy process but takes a little time and care, the good part is you not only get a larger diameter but generally a much rounder bullet in the process.

one other method of gaining a couple thou in diameter is to powder coat the bullets in lieu of lube sizing them.
Blind Hawg
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Re: Bullet bumping

Post by Blind Hawg »

I lapped my Lee .429 200 mold today and gained .001”. That gain and powder coating will get me closer to where I need to be without spending $100 on a custom mold and a set of handles. Thanks!!!
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Re: Bullet bumping

Post by Archer »

9x80Drilling
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Re: Bullet bumping

Post by 9x80Drilling »

Is it possible to bump up a jacketed bullet? Is it feasible?
I ask because I have used .358" Nosler Partitions in my 9x80 drilling, bore size .362". Accuracy is acceptable for deer, elk, and antelope out to 125 yards. I'd like to improve on that.
Thanks.
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Re: Bullet bumping

Post by Archer »

https://www.nosler.com/partition-bullet/

You are talking about bumping up the diameter on a copper I-beam construction cylinder.
IMO it is not worth the trouble to try any bumping scheme.

IT might be possible to powder coat such a bullet.
IT might be possible to paper patch such a bullet.
https://www.montanabulletworks.com/bull ... h-bullets/

Either way you would have to load the bullet using a similar technique to loading a soft lead bullet. That is to say you probably need a Lyman M type die to flare the case mouth and you need to turn the flare back straight after the fact with a crimp die. I would recommend doing the seat operation independent of the operation to turn the case neck back. Some sources recommend the use of a taper crimp die.

http://castboolits.gunloads.com/showthr ... ed-bullets

https://www.thefreelibrary.com/Making+O ... 0535421727

https://svartkrutt.net/articles/vis.php ... introduced.
9x80Drilling
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Re: Bullet bumping

Post by 9x80Drilling »

Archer, thanks for the ideas and those links. I enjoyed reading all of them tonight.

I have paper patched jacketed bullets for a couple of odd calibers following Ross Seyfried's advice. This was a good 20 years ago. It's actually time for me to try again. It's also time for me to start loading cast for these odd bores.
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