On Thu, 05 Sep 2013 23:30:26 -0700, pyotr filipivich
wrote:
John B. on Fri, 06 Sep 2013 12:01:07 +0700 typed
in rec.crafts.metalworking the following:
On Thu, 05 Sep 2013 11:41:19 -0700, pyotr filipivich
wrote:
Greetings
I have a couple questions on bullet sizes and barrel thickness.
In order to keep my hand in over summer break, I'm in the midst of
a CAD project. Maybe I can learn a few things too, about CAD, Catia
and the object of my project.
Yes, for "grins and giggles", I am attempting to gin up drawings
for the 6.35 mm "Pistola Con Caricato". The three barrel 18 shot one
off from the 1920's. Yeah, that one.
So, I have the SAAMI pdf with the dimension of the standard .25
cal / 6.35x16mmSR Browning cartridge. "Way cool" - but it did cause a
bit of "redrawing" as I had made preliminary drawings with a dimension
of 6.35 mm. "oops" (Actually, I was trying to get the geometry
sorted out, how to get lines to start where I wanted them, instead of
the apparent random location the program defaults to.)
Anyway, I now have a nice profile of a standard 6.36x16mmSR round
- bullet and cartridge. [23.11 mm OAL, as per spec]. What I don't
know however is: how long is the bullet itself?
"As Drawn" the bullet has nothing inside the brass to hold it
together. While this may not be a serious problem for merely drafting
a chamber for the cartridge, it offends my Professional Standards to
not have a "real bullet" correctly sized which can then be matched up
with the cartridge, and then that Assembly inserted into the Cylinder
Unit.
So, my questions:
1) Does anyone have the specs for the bullets themselves? Or a
link to where those same specs can be found?
Bullet diameter is 0.251".
Length?
--
pyotr filipivich
"With Age comes Wisdom. Although more often, Age travels alone."
I'm not exactly sure what you are asking. I believe that all the
Browning cartridges head space on the case mouth, at least the ones I
had anything to do with did (although on second thought some of them
are semi-rimed I think). I think that you are talking about the
dimensions of the part of the bullet that sticks out of the case,
which, other then overall length, isn't much of consideration, at
least for a .25 Browning.
With pullets shot out of an "automatic pistol" the radius of the
bullet point is more to do with the feeding of the cartridge into the
barrel then anything else.
There is a short tapered portion of the interior of the barrel, just
ahead of the chamber shoulder but that is more a factor of the bullet
being squeezed into the rifling. A revolver that seats the cartridges
outside the barrel still has a "forcing cone" - a short taper in the
rear of the barrel.
See
http://www.trackofthewolf.com/List/I.../1/LINER-40-65
for bore, lands and grooves measurements.
By the way, the above site says that a ".25 Colt Auto" is a 1 turn in
14 inches twist while I've seen it listed a 1-16 elsewhere.
--
Cheers,
John B.