The Firing Line Forums

Go Back   The Firing Line Forums > The Skunkworks > The Harley Nolden Memorial Institute for Firearms Research

Reply
 
Thread Tools Search this Thread
Old August 15, 2020, 11:05 AM   #26
Double K
Senior Member
 
Join Date: June 16, 2020
Location: Colorado
Posts: 486
It's human nature to experiment and push boundaries in everything around us, some people are less curious than others about what is possible and isn't.
To me that was a waste for my engineer friend to ruin that 700bdl{he eventually ruined the action as well} but it was his gun to do with as he pleased.
Double K is offline  
Old August 18, 2020, 05:04 AM   #27
Hal
Senior Member
 
Join Date: October 9, 1998
Location: Ohio USA
Posts: 8,563
Quote:
one would think accuracy and dependability would outweigh the need for speed. why so much desire for speed in todays ballistic world? just a novices' question.
On the practical side - increased velocity delivers more potential distance & flattens out the trajectory.

On the not so practical side - "Hold my beer and watch this" and/or "look what I can do"...
Hal is offline  
Old August 23, 2020, 11:38 AM   #28
Ricklin
Senior Member
 
Join Date: February 22, 2008
Location: SW Washington state
Posts: 1,798
Your old time engineer friend might want to broaden their knowledge base. The high speed dental turbine handpiece routinely turns at 400 thousand RPM, some go as high as 500 Thousand RPM.
They tend to be "all" RPM and "no" torque. With a diamond cutting instrument I know of no material that can't be cut.
The newer electric high speed handpiece attains a max. of 200 thousand RPM, Hand pressure alone will not stall the cutting instrument. It will cause the cutting instrument (bur) to fail violently. Yes, you can put out an eye with one.
My engineers loved the fact I had one. Perfect tool to modify a production mold they screwed up on. A diamond in a high speed handpiece did the trick.

Handy tip. Diamonds are cheap nowadays. One can purchase a chuck for Dremel or Foredom tools for dental size diamond burs. The variety of shapes and sizes is amazing. The burs are available under a dollar each. I modified the Borosilicate glass print bed for my 3d printer, quick and easy with a diamond.
__________________
ricklin
Freedom is not free

Last edited by Ricklin; August 23, 2020 at 11:43 AM.
Ricklin is offline  
Old August 23, 2020, 01:50 PM   #29
Double K
Senior Member
 
Join Date: June 16, 2020
Location: Colorado
Posts: 486
Quote:
Originally Posted by Ricklin View Post
Your old time engineer friend might want to broaden their knowledge base. The high speed dental turbine handpiece routinely turns at 400 thousand RPM, some go as high as 500 Thousand RPM.
They tend to be "all" RPM and "no" torque. With a diamond cutting instrument I know of no material that can't be cut.
The newer electric high speed handpiece attains a max. of 200 thousand RPM, Hand pressure alone will not stall the cutting instrument. It will cause the cutting instrument (bur) to fail violently. Yes, you can put out an eye with one.
My engineers loved the fact I had one. Perfect tool to modify a production mold they screwed up on. A diamond in a high speed handpiece did the trick.

Handy tip. Diamonds are cheap nowadays. One can purchase a chuck for Dremel or Foredom tools for dental size diamond burs. The variety of shapes and sizes is amazing. The burs are available under a dollar each. I modified the Borosilicate glass print bed for my 3d printer, quick and easy with a diamond.
Probably should have mentioned that was in 1978, technology has changed a good bit since then.
Double K is offline  
Old August 29, 2020, 10:44 AM   #30
Ricklin
Senior Member
 
Join Date: February 22, 2008
Location: SW Washington state
Posts: 1,798
Way before that

The high speed turbine handpiece was invented in the early 60's, may have even been a touch earlier. It's not new technology by any measure.

What is fairly new is the lower cost of diamonds. High quality diamond burs (the cutter) used to cost 5 bucks each. They are now about one dollar each.
__________________
ricklin
Freedom is not free
Ricklin is offline  
Old August 29, 2020, 11:04 AM   #31
TRX
Senior Member
 
Join Date: September 24, 2008
Location: central Arkansas
Posts: 390
> Yep. Never tried them but some people said they shot as well as the rifle in question would shoot normal ammo.
---
That turned out to be highly variable. Remington developed their .30-06 and .308 saboted rounds with normal production Remington rifle barrels; .002-.003 deep rifling with 1:10 twist. Unfortunately the rest of the industry was moving to slightly shallower rifling (jackets were getting harder and thicker for some hunting rounds) and they were backing off to 1:12 or even 1:14 twist to stabilize the lighter, pointier bullets that were becoming popular. On those rifles, the sabots would sometimes strip instead of spinning the bullet, and the slower twists didn't stabilize them enough for best accuracy.

That's why you see so many head-butting contests polarized at "I used them and they were great!" and "I used them and they shot like corkscrews!"

Remington also made the Accelerator for the .30-30. Twists and groove depth are all over the place on those, but I don't think they sold very many.

The Accelerators have been out of production for quite some time now, but if you want to give the idea a try, EABCO sells their own design of plastic sabots and a special bullet seating tool for quite reasonable prices. They also have loading data. Remington's .30-06 loads had 55 grain bullets at >4000fps, solid .220 Swift territory.
TRX is offline  
Old September 3, 2020, 12:49 AM   #32
JohnKSa
Staff
 
Join Date: February 12, 2001
Location: DFW Area
Posts: 24,239
I found a silly (but entertaining) video on youtube. They set up a .38sp chamber with a long smoothbore barrel and fired 6mm aluminum balls using .38SP blanks.

A full load achieved over 4600fps muzzle velocity.

https://www.youtube.com/watch?v=obH3gnCGXu0

Here's a second video trying some hotter loads.

https://www.youtube.com/watch?v=JpGFCX82IQs

Over 5250fps.
__________________
Do you know about the TEXAS State Rifle Association?
JohnKSa is offline  
Old December 31, 2021, 09:56 PM   #33
Grey_Lion
Senior Member
 
Join Date: April 15, 2018
Location: Baton Rouge - Louisiana
Posts: 396
For those mentioning rail guns - here ya go - enjoy -https://futurism.com/company-selling...WZVTfgKwz-ermw
Grey_Lion is offline  
Old December 31, 2021, 10:00 PM   #34
Grey_Lion
Senior Member
 
Join Date: April 15, 2018
Location: Baton Rouge - Louisiana
Posts: 396
Navy has been playing with rail guns but reading some of their initial results indicates that they go through launch tubes like crazy as they wear out.

I'm aware that some conventional different results might be had with solid copper projectiles that behave differently under extreme pressures than FMJ rounds so that might lead you in a different direction in your research.
Grey_Lion is offline  
Old January 21, 2022, 12:32 AM   #35
44 AMP
Staff
 
Join Date: March 11, 2006
Location: Upper US
Posts: 25,572
The Internet says escape velocity is 36,699 fps. i'd say that's the fastest possible speed ON EARTH.
__________________
All else being equal (and it almost never is) bigger bullets tend to work better.
44 AMP is offline  
Old February 20, 2022, 09:22 AM   #36
TXAZ
Senior Member
 
Join Date: September 5, 2010
Location: McMurdo Sound Texas
Posts: 4,316
If a rail gun is fair game, then consider the ion thruster / ion gun, ant an electron gun found in older CRT-based TV’s.
https://www.nasa.gov/centers/glenn/t...opulsion1.html

NASA says …” often used just one at a time. Spacecraft powered by these thrusters can reach speeds up to 90,000 meters per second (over 200,000 mph). In comparison, the Space Shuttles can reach speeds around 18,000 mph.”
The muzzle velocity of the ions coming out (in a vacuum, in space or on a test rig on earth) is on the order of the speed of light, 300,000 Km/sec).


Conversely, you can build your own “Electron gun” (or pull it out of an old TV tube) and reach speeds over 13 million mph.
And this gun can kill if pointed at a very close target for extended periods of time).

“For an electron gun with a voltage between its cathode and anode of V = 100V the electron will have a speed of about v = 6 × 10^6 m/s.”
https://spark.iop.org › speed-electrons
The speed of electrons | IOPSpark - Institute of Physics
__________________

Cave illos in guns et backhoes

Last edited by TXAZ; February 20, 2022 at 09:40 AM.
TXAZ is offline  
Old March 4, 2022, 12:52 PM   #37
Ricklin
Senior Member
 
Join Date: February 22, 2008
Location: SW Washington state
Posts: 1,798
Very cool

Professionally I am a Radiology guy.
One of the darn few new products that still employ a vacuum tube. X-ray generators, radar, and microwave ovens are the only common items I can think of, I'm sure there are others.

High voltage required, 45,000 - 120,000 volts on the anode for human diagnostics.
I'm a careful sort, that kind of voltage can make you a pile of ashes. I'm old, not bold.
186,282 miles per second in a vacuum, the ballpark speed of light. Classic physics. Einstein.

That may or may not be the "real" speed limit of the universe, stay tuned!
__________________
ricklin
Freedom is not free

Last edited by Ricklin; March 4, 2022 at 12:59 PM.
Ricklin is offline  
Old March 21, 2022, 06:34 AM   #38
stuckinthe60s
Senior Member
 
Join Date: January 31, 2017
Location: Va., Ct., Mo..
Posts: 583
what year did those navy /army bullets get issued?
__________________
Retired Military Aviation
Former Member Navy Shooting Team
Distinguished Pistol Shot,NRA Shotgun/Pistol Instructor
NSSA All American, Skeet/Trap Range Owner
stuckinthe60s is offline  
Old March 27, 2022, 02:51 PM   #39
mrmeval
Junior Member
 
Join Date: September 25, 2008
Posts: 4
I worked with a friend in the 90s. He worked up some max loads for .30-06. In one test the bullets never got to the chronograph. So we set up some paper targets facing each other to see where they were dying as he suspected they were disintegrating from the rotation or had terrible accuracy.

They were disintegrating, they peppered the paper at a few feet before the chronograph. The previous loading had hit 4k in a .30-06 with poor accuracy.

In another test a non-Remington .30 cal sabot for .22 bullet was used with a 5.56 bullet pulled from a old cartridges. This was loaded in a .308 and it did well on speed at about 4200 but accuracy was poor till he dropped the FPS down to around 3800. Accuracy was meager but close to a bolt action .223 rifle.
mrmeval is offline  
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 12:02 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2022, vBulletin Solutions, Inc.
This site and contents, including all posts, Copyright © 1998-2021 S.W.A.T. Magazine
Copyright Complaints: Please direct DMCA Takedown Notices to the registered agent: thefiringline.com
Page generated in 0.04911 seconds with 10 queries