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Barrel rifling
- Thread starter BoltGunner054
- Start date
Agreed.
In my opinion reamers cutting chambers that have a tapered body and angled shoulder will be stabilized by those tapers while cutting under load to a degree far exceeding any theoretical bounce or vibration caused by flute count vs groove count.
Is Mark still around? I bought some barrels from him in 2013-2015. Super guy as well but I haven't heard from him in a long time.
Probably won't be able to replicate it by pushing a slug or anything like that into the barrel. Rounds would need to be fired down the barrel and either the bullets recovered and or high speed photography would be needed.
This issued showed up with high pressure/high velocity when this test was conducted. Pressures going over 65k and velocities hitting 3000fps and faster.
The test that Hornady ran years ago along with the Army that same year for the most part it was normal loads/pressures and velocities but they both seen the same thing.... the bullets out of the 5R rifled barrels flew more consistently at long range than out of the 4 groove and 6 groove conventional rifled barrels. They didn't know why but they seen the same thing... BC of the bullets was more consistent.
At short range...say under 500 yards.... for the most part you won't see it on paper but the greater the distance.... any slight changes effecting the BC of the bullet shows up more.
Drag consistency has been discussed more in recent months than I can recall in many years.
The average consumer now has the ability to actually measure it without "breaking the bank".
Two Garmins will give you a MV and a downrange velocity. Hard part is shooting within the appropriate place near but not on the downrange Garmin. I know it has been done at 800 meters. They only lost 1 Garmin.
I've heard about the Shot Marker system but don't have any experience with it. It may have the capabilty to provide downrange velocity and/or time of flight. From what I've heard, the downrange projectile must be supersonic for it to work.
I have extensive experience with the Oehler System '89, have actually used it at 2 miles. Not many have actually begun to use it. My opinion was because it had skyscreens. It now will work with an outside MV source (Garmin, Labradar, Magnetospeed...whatever you trust).
The system is much easier to use now and will provide reliable data - I've run it beside Infinition radar and they gave the same numbers.
These are exciting times to be experimenting with projectile drag.
The average consumer now has the ability to actually measure it without "breaking the bank".
Two Garmins will give you a MV and a downrange velocity. Hard part is shooting within the appropriate place near but not on the downrange Garmin. I know it has been done at 800 meters. They only lost 1 Garmin.
I've heard about the Shot Marker system but don't have any experience with it. It may have the capabilty to provide downrange velocity and/or time of flight. From what I've heard, the downrange projectile must be supersonic for it to work.
I have extensive experience with the Oehler System '89, have actually used it at 2 miles. Not many have actually begun to use it. My opinion was because it had skyscreens. It now will work with an outside MV source (Garmin, Labradar, Magnetospeed...whatever you trust).
The system is much easier to use now and will provide reliable data - I've run it beside Infinition radar and they gave the same numbers.
These are exciting times to be experimenting with projectile drag.
I have used a shot marker for years, since it came out. It made my life much easier than rolling out all the wires I had setup for my acoustic chrono that I built 15 years ago. So far only one genius has felt the need to take shots at the colored things on the corner of the frame while I was at the range with it.
The garmin makes it really easy to setup, but I used it for years with a LabRadar and the Shot Marker and it worked very well.
I forgot, gun smiffin’ is stuck in the stone age of machine technology and theory.
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I looked the Shot Marker up and it certainly seems to be a good piece of kit.
In the spirit of "Trust but verify", have you ever put a Garmin or other chronograph downrange to verify the Shot Marker is giving a reliable velocity measurement?
Off topic, but yes, I confirmed it at short range with the LabRadar when I had both still tracking and I put my own microphones against this one and got data downrange. It's not doppler, but for what it costs I'm hard pressed to find something else that does such a good job for so little money.
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