9.3X62AL
05-30-2006, 07:47 PM
There's NOTHING like spending the day in a courthouse witness room to prompt random ponderings, and missing the Burrito Match added to the overall dissatisfaction of the day's results--and I get to go back tomorrow for more of the same rigamarole, what an unalloyed joy.
This year's "leased" moold from Onceabull is an interesting design--a one cavity aluminum Rapine #460510, which is pretty much a 45 caliber rifle Loverin design--8 skinny drive bands/7 small lube grooves, and a short truncated-cone nose. Having not yet poured castings, I haven't confirmed its "as-cast" diameters, but the Mark I No. 3 eyeball shows them all to likely be full diameter, whatever that turns out to be.
The length of this critter might cause a few powder space issues in my Ruger #1 x 45-70 in this caliber, and would do the same for a Marlin 95 or Win 86--assuming you wanted to run 510 grain boolits in a rifle so chambered. Before we go much further, I want it known that I'm not keenly interested in getting this boolit anywhere near the design-strength limit of the Ruger pressure-wise. I've already seen the movie that features 400 grain+ bullets going at 1800 FPS+ from this 7-1/4# package, so been there/done that/got the T-shirt. What I'm trying to prevent is boolit bases running into the case's inside taper and distending the case walls like a snake that ate a big rat.
With that in mind, and knowing the land diameter of my Ruger to be .449", I'm considering a sizer die that would enable the boolit's leading drive bands--2 to 4 of them--to be sized down to that dimension, thus enabling a longer cartridge overall length/less deeply-seated boolit in the single shot Ruger.
Further--the Mountain Molds Fat Thirty 190 grainer I'm using in my Lee-Enfield and Mosin-Nagant is Dan's typical tangent ogive/flat nose form, with full-diameter nose extending .100" forward of the primary drive bands. In the Lee-Enfield, this boolit's design requires fairly deep seating to enable chambering, and while it's not the end of the world to have lubed drive bands extending into the powder space, it's nice to not be required to do so. A similar approach to this issue--sizing the nose down to "bore-rider" dimensions could be a solution.
Has anyone else given this "nose sizing" bit a try? I was thinking that sizing and lubing the drive bands first, then turning boolit upside down and sizing the nose last would be preferable. Lube in at least one of the nose-end grooves might be a good idea to ease passage of the bore rider, and I'm thinking that sizing from .460" down to .449" might best be done in 2 or more steps. I know that a purpose-built mold with proper as-cast dimensions is the BEST answer, but doing things right misses the point I'm driving at (did I really say that?).
Whaddaya think, folks?
This year's "leased" moold from Onceabull is an interesting design--a one cavity aluminum Rapine #460510, which is pretty much a 45 caliber rifle Loverin design--8 skinny drive bands/7 small lube grooves, and a short truncated-cone nose. Having not yet poured castings, I haven't confirmed its "as-cast" diameters, but the Mark I No. 3 eyeball shows them all to likely be full diameter, whatever that turns out to be.
The length of this critter might cause a few powder space issues in my Ruger #1 x 45-70 in this caliber, and would do the same for a Marlin 95 or Win 86--assuming you wanted to run 510 grain boolits in a rifle so chambered. Before we go much further, I want it known that I'm not keenly interested in getting this boolit anywhere near the design-strength limit of the Ruger pressure-wise. I've already seen the movie that features 400 grain+ bullets going at 1800 FPS+ from this 7-1/4# package, so been there/done that/got the T-shirt. What I'm trying to prevent is boolit bases running into the case's inside taper and distending the case walls like a snake that ate a big rat.
With that in mind, and knowing the land diameter of my Ruger to be .449", I'm considering a sizer die that would enable the boolit's leading drive bands--2 to 4 of them--to be sized down to that dimension, thus enabling a longer cartridge overall length/less deeply-seated boolit in the single shot Ruger.
Further--the Mountain Molds Fat Thirty 190 grainer I'm using in my Lee-Enfield and Mosin-Nagant is Dan's typical tangent ogive/flat nose form, with full-diameter nose extending .100" forward of the primary drive bands. In the Lee-Enfield, this boolit's design requires fairly deep seating to enable chambering, and while it's not the end of the world to have lubed drive bands extending into the powder space, it's nice to not be required to do so. A similar approach to this issue--sizing the nose down to "bore-rider" dimensions could be a solution.
Has anyone else given this "nose sizing" bit a try? I was thinking that sizing and lubing the drive bands first, then turning boolit upside down and sizing the nose last would be preferable. Lube in at least one of the nose-end grooves might be a good idea to ease passage of the bore rider, and I'm thinking that sizing from .460" down to .449" might best be done in 2 or more steps. I know that a purpose-built mold with proper as-cast dimensions is the BEST answer, but doing things right misses the point I'm driving at (did I really say that?).
Whaddaya think, folks?