photo Dragoon-Navyset_zps3txqpebh.jpg

Author Topic: pietta '60' army and conicals  (Read 782 times)

Offline bigted

  • Full Member
  • ***
  • Posts: 216
  • when all is said ... more will be said then done.
    • View Profile
pietta '60' army and conicals
« on: January 15, 2017, 05:18:19 PM »
well by "accidentally on purpose" i discovered a new bullet to load in my army colt revolver. upon messing with the 51 i began to wonder what it would take to make the Lee tumble lube 200 grain .452 diameter bullet work in my 60 colt.

so wondering out to the shop i took a couple of these bullets cast of pure lead and turned one upside down and turned the cylinder till the upside down [nose in the chamber] was under the rammer. well this went smoothly so i retracted the bullet and smeared SPG lube on the tumble lube grooves. now installing it back under the rammer again upside down i half heartedly used the rammer to shove the bullet half into the cylinder. this went so smooth i just rammed it all the way into the cylinder and wiped off the resultant "ring" of lead off the cylinder face.

gotta say they look cool in the cylinder upside down and filling the whole mouth with lead.

so took another and lubed it likewise and rammed it home as well. now removing the cylinder i hoped i had a punch that would shove em back out thru the nipple hole ... yep had a brass punch just made for such stupid's.

now that i know they will chamber and be below the mouth of the chamber ... guess i need to discover how much 3Fg powder will fit into the cylinder and allow it to be seated just below the chamber mouth

cap n ball FULL WADCUTTER man ... and in 44 cal ... anybody else fooled with such a thing?
BIGTED

Offline Captainkirk

  • Administrator Extraordinaire and Part-Time Gunslinger
  • Administrator
  • Hero Member
  • *****
  • Posts: 3802
  • "Nothing like a nice piece of hickory"
    • View Profile
Re: pietta '60' army and conicals
« Reply #1 on: January 15, 2017, 07:07:49 PM »
Ummm...yep. Cap'n Walker's Texas Rangers. One of the theories of the 'sploding Walkers was that some of the Rangers couldn't figure out which way them newfangled 'picket bullets' were supposed to load, and figured "path of least resistance" was loading the pointy end first thus creating a huge pressure spike when the headstand bullets tried to shove the ass-end through the forcing cone...
There are other theories, of course (including poor quality steel) but the proponents of this particular theory are fairly well set in their beliefs. Remember; even a wadcutter has some taper to the point. They also point to the fact that the burning charge no longer has a flat base to obturate, but a taper which allows the burning charge to expand into the area between cylinder wall and projectile rather than pushing against the piston-shaped base.
Naturally, the Walkers held a bit more powder (up to 60gr) in comparison to a '60 Army (maybe 40gr max with a conical).
Do I buy this 100%? No, but there is a grain or two of merit in the theory.
Just throwin' that out there.
"You gonna pull those pistols, or whistle Dixie?"

Offline prof marvel

  • Jr. Member
  • **
  • Posts: 77
  • Newbie
    • View Profile
Re: pietta '60' army and conicals
« Reply #2 on: January 15, 2017, 10:15:50 PM »
I must concurr with Capt Kirk -

please note that the pressure is measured in  "pounds per square inch".
on a flat based .44 bullet the area acted upon ( assuming a .445 bullet after squishing into the chamber) is  .1554 square inches.

the nose of the bullet will present significantly more surface area. since the nose is sort of paraboloid surface area is .40886 sq in,
so the pressure will be 2.6 times that of the flat based bullet!

If , with black powder with a flat based bullet , you are getting a chamber pressure of say, 10,000 psi,  by loading with the "point down" you could be seeing as much as 31,500 psi against the "base"

by contrast a roundball ( for pressure purposes we are looking at a "spherical section" rather than a true half-sphere ) we have a surface area of .2512 square inches and would see a pressure of  ~ 16,000 psi on the "base"


remember, your milage will vary with the actual surface area, numbers, etc.

but I would not chance it.

yhs
prof marvel
« Last Edit: January 15, 2017, 10:32:30 PM by prof marvel »

Offline bigted

  • Full Member
  • ***
  • Posts: 216
  • when all is said ... more will be said then done.
    • View Profile
Re: pietta '60' army and conicals
« Reply #3 on: January 16, 2017, 07:56:28 AM »
No argument here ... Just a question or two ... 1- how does this effect the pressure on deep hollow based bullets such as the Minnie bullet? 2- all the flat nose bullets I have (357) aren't tapered in the least and they are also hollow based bullets.

I am not too educated in the numbers game so I have to try to understand from those whom would share their knowledge with me. Thanks for the share and education.
BIGTED

Offline Captainkirk

  • Administrator Extraordinaire and Part-Time Gunslinger
  • Administrator
  • Hero Member
  • *****
  • Posts: 3802
  • "Nothing like a nice piece of hickory"
    • View Profile
Re: pietta '60' army and conicals
« Reply #4 on: January 16, 2017, 08:42:46 AM »
I'm no engineer, Bigted, but it seems to me that the pressure wave on a hollow based minie' would be quite different; it would be working to expand the thin skirt edges and push against the inner base of the bullet while a backwards bullet would have the wave trying to expand a solid mass in the center of the chamber, and having no give, would expend the energy pushing OUT on the cylinder burning towards a decreasing space...like quench in an internal combustion engine cylinder. I can see in my mind's eye where it could induce a failure in a weak cylinder or create dangerous pressure spikes in excess of design.
If it were me, I'd leave that sleeping dog lie.
"You gonna pull those pistols, or whistle Dixie?"

Offline bigted

  • Full Member
  • ***
  • Posts: 216
  • when all is said ... more will be said then done.
    • View Profile
Re: pietta '60' army and conicals
« Reply #5 on: January 17, 2017, 01:25:44 PM »
OK ... now we are talking something i know a bit about ... engines.

never made the connection between cubic inch engine performance and a bullet action with the same sort of combustion. be like installing a shaved head or more like a higher dome piston to increase the compression. YES i can now see your point. thanks for the object lesson.

i will leave the bullets rite side up and load em in what they were designed for.

thanks again for the lesson/comparison ... sunk into me noggin finally. the hollow based bullets actually increase the area and capacity for the cylinder/chamber ... thus reducing pressure/compression.
BIGTED

Offline Captainkirk

  • Administrator Extraordinaire and Part-Time Gunslinger
  • Administrator
  • Hero Member
  • *****
  • Posts: 3802
  • "Nothing like a nice piece of hickory"
    • View Profile
Re: pietta '60' army and conicals
« Reply #6 on: January 17, 2017, 08:50:26 PM »
Yeah, engines are something I know a little bit about myownself. L@J
"You gonna pull those pistols, or whistle Dixie?"

Offline HAWKEN50

  • Full Member
  • ***
  • Posts: 168
  • Newbie
    • View Profile
Re: pietta '60' army and conicals
« Reply #7 on: January 18, 2017, 04:27:56 AM »
 :o  Yep load em flat base down, With the nose down it would be like a shaped charge
« Last Edit: January 28, 2017, 04:11:28 PM by HAWKEN50 »

Offline ssb73q

  • Hero Member
  • *****
  • Posts: 1999
  • Gunsmoke junkie
    • View Profile
Re: pietta '60' army and conicals
« Reply #8 on: January 18, 2017, 09:49:04 AM »
:o  Yep load em flat base down, With the nose gown it would be like a shaped charge

Hi HAWKEN50, I agree in principle.

Regards,
Richard
There’s nothing better in the morning than the smell of bacon and black powder smoke!

Offline prof marvel

  • Jr. Member
  • **
  • Posts: 77
  • Newbie
    • View Profile
Re: pietta '60' army and conicals
« Reply #9 on: January 19, 2017, 12:11:52 AM »
:o  Yep load em flat base down, With the nose gown it would be like a shaped charge

THAT ^^^

that pretty much sums it up in one sentence. Thanks Hawken

yhs
prf marvl

Offline bigted

  • Full Member
  • ***
  • Posts: 216
  • when all is said ... more will be said then done.
    • View Profile
Re: pietta '60' army and conicals
« Reply #10 on: January 28, 2017, 03:30:20 PM »
abandon the idea as ... what do my wife call me time to time ... SIMPLE. anyway i have the Lee molds for both 36 and my 44's so i will stick with them and use them other rascals for their intended purpose.

thanks for the replys all and this the reason i like to bounce some of my thoughts and urges on you folks ... easy sightin from outside the brush pile. (7&
BIGTED