Bullet Diameter vs Cylinder Throat Diameter
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Archie
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Uh.....
.6293 ?
Nominal bore diameter of a 44 Magnum is .429....
Presuming a typo....
What you want to check is the bore diameter, also. You want the bore diameter to be a little less (.0003 less would be fine) than the cylinder throats. You do not want the bore to be bigger, as the bullet may not fill out the bore and the rifling may not engage the bullet properly.
As to the diameter of jacketed bullet, the manufacturers make 44 caliber bullets normally .429". Someone makes one in .430" but I can'r remember who. If you are going to make your own jacketed bullets, make them to fit the chamber throat, or a thousandth over.
It really doesn't matter, as when the round goes off, it will upset and fill out the cylinder throat. In effect, it gets resized. Then when the bullet gets into the rifling, the ogive of the bullet slows down, but the base is still accelerating, so it again is resized to fit the bore.
It's almost as complicated as Congress.
.6293 ?
Nominal bore diameter of a 44 Magnum is .429....
Presuming a typo....
What you want to check is the bore diameter, also. You want the bore diameter to be a little less (.0003 less would be fine) than the cylinder throats. You do not want the bore to be bigger, as the bullet may not fill out the bore and the rifling may not engage the bullet properly.
As to the diameter of jacketed bullet, the manufacturers make 44 caliber bullets normally .429". Someone makes one in .430" but I can'r remember who. If you are going to make your own jacketed bullets, make them to fit the chamber throat, or a thousandth over.
It really doesn't matter, as when the round goes off, it will upset and fill out the cylinder throat. In effect, it gets resized. Then when the bullet gets into the rifling, the ogive of the bullet slows down, but the base is still accelerating, so it again is resized to fit the bore.
It's almost as complicated as Congress.
xtarheel
Member
If it is .629, you can probably shoot a 20 guage shotgun shell through it! I'm sure you meant .429. The recomended throat diameter for a .44 is .4325 (recomended by the folks at Manson ), many cast 44 bullets run about .430.
This gradual step-down to groove diameter through throats of a consistant diameter tends to yield the best accuracy.
.4295 is what I would look for in a jacketed bullet
This gradual step-down to groove diameter through throats of a consistant diameter tends to yield the best accuracy.
.4295 is what I would look for in a jacketed bullet
.4293
Actually you could probably go slightly larger but might increase pressures.
Many jacketed bullets do not measure what the boxes say they measure. Unless you run into some old undersize .44-40 bullets just buy standard .44 Mag/Special bullets and don't worry about it.
There isn't much point in slugging your barrel in the revolver for jacketed use and even if you were loading cast, the cylinder throat is the dimension you size to. S&Ws are five groove rifled anyway, obviating normal measuring--you'de need a 'V' block in addition to your micrometer.
Jacketed bullets are much more forgiving than cast so if your groove diameter was .431, for example, it would likely still shoot fine with .429 bullets.
Actually you could probably go slightly larger but might increase pressures.
Many jacketed bullets do not measure what the boxes say they measure. Unless you run into some old undersize .44-40 bullets just buy standard .44 Mag/Special bullets and don't worry about it.
There isn't much point in slugging your barrel in the revolver for jacketed use and even if you were loading cast, the cylinder throat is the dimension you size to. S&Ws are five groove rifled anyway, obviating normal measuring--you'de need a 'V' block in addition to your micrometer.
Jacketed bullets are much more forgiving than cast so if your groove diameter was .431, for example, it would likely still shoot fine with .429 bullets.
CORRECTION - .4293 Throat Diameter
Sorry about that. I meant .4293 throat diameter.
I am wondering what happens if I try to shoot some Hornady 240gr HP/XTP jacketed hollow points. They are .4298 diameter, or .0005 bigger than the throat holes. High pressure? Thanks. 44
Sorry about that. I meant .4293 throat diameter.
I am wondering what happens if I try to shoot some Hornady 240gr HP/XTP jacketed hollow points. They are .4298 diameter, or .0005 bigger than the throat holes. High pressure? Thanks. 44
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Bullet Sizes
Here are the diameters of the 44mag Jacketed bullets I want to handload in the gun with .4293 throat diameters:
-- Speer 240gr GDHP........... .4292
-- Speer 240gr GDFP............ .4293
-- Speer 270gr GDFP............ .4295
-- Sierra Target.................... .4294
-- Sierra Target.................... .4293
-- Win 210gr STHP............... .4298 to .4306 (out of round)
-- Hornady 240gr HP/XTP.... .4298
Looks like most of them should be OK? What about the STHP and the XTP? Thanks. 44
Here are the diameters of the 44mag Jacketed bullets I want to handload in the gun with .4293 throat diameters:
-- Speer 240gr GDHP........... .4292
-- Speer 240gr GDFP............ .4293
-- Speer 270gr GDFP............ .4295
-- Sierra Target.................... .4294
-- Sierra Target.................... .4293
-- Win 210gr STHP............... .4298 to .4306 (out of round)
-- Hornady 240gr HP/XTP.... .4298
Looks like most of them should be OK? What about the STHP and the XTP? Thanks. 44
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They are ALL FINE, just load up with published and verified data and have fun. You can shoot .430" jacketed bullets with published load data just fine. For lead bullets I would have the throats reamed to .4305-.431", my guess is the barrel will lead more than it should the way it currently is. If the gun is accurate right now and you shoot only jacketed bullets leave it alone, if accuracy is so-so I would have the throats cut as it will not hurt anything if done well, and could make a decent gun an outstanding one.
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