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Old August 15, 2020, 11:05 AM   #26
Double K
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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.
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Old August 18, 2020, 05:04 AM   #27
Hal
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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"...
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Old August 23, 2020, 11:38 AM   #28
Ricklin
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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.
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Old August 23, 2020, 01:50 PM   #29
Double K
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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.
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Old August 29, 2020, 10:44 AM   #30
Ricklin
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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.
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Old August 29, 2020, 11:04 AM   #31
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> 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.
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Old September 3, 2020, 12:49 AM   #32
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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.
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