Barrel rifling

[Haney]

Don't get too hung up on this. Most builders (myself included) may have preferences that work slightly better with our particular setups.....but by no means are we putting out substandard work otherwise. As pointed out here, there are many more influential variables that can be (and should be) chased instead.

Ern

You nailed it, experience is the best teacher.

 

[Terry Cross]

Don't get too hung up on this. Most builders (myself included) may have preferences that work slightly better with our particular setups.....but by no means are we putting out substandard work otherwise. As pointed out here, there are many more influential variables that can be (and should be) chased instead.

Ern

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.

 

[high right]

Boots was cool to talk to! If you got him started... don't hang up the phone!

Him and Jim were very tight! Jim ran RCLRC range back in the 80's and 90's. Boots made his barrels and did the install work etc... for Jim most of the time. A few guys convinced Jim to start teaching classes for hi power shooting to help new shooters coming into the sport. I'm happy to say I was in on the 2nd class he did and took a few more after that. You always learned/came away with some new knowledge. I'd say Jim was right in the regards it probably cut 3-5 years off of a new shooters learning curve. During the course of the classes Jim also got a gun builder or two (custom smiths) and go over builds etc... and then in another class usually Boots or John Krieger came in and talked about barrels.

Boots was as good of a barrel maker as he was a gunsmith (that's how it started for them... his family owned a gun store in Racine....and then he went to gunsmithing school and then shortly after that he got some equipment and started making barrels) as well as he was an excellent hi power shooter. Pulling his targets was pretty cool to say the least. Talk about a guy who could just pound the center of the target with iron sights let alone a scope. One of the matches I was at and if I recall correctly he won it as well... he laughed after the match and someone asked what was so funny? He said he just realized he grabbed the wrong ammo....he brought his culls/practice ammo to the match instead of his match ammo! Like I said... the guy could shoot also!

Later, Frank

You ever run into a guy named Mark Chanlynn when at Boots?

 

[bohem]

You ever run into a guy named Mark Chanlynn when at Boots?

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.

 

[Frank Green]

You ever run into a guy named Mark Chanlynn when at Boots?

I know who Chanlynn is but no... never met him.

 

[Frank Green]

Thanks! That's really interesting, it looks like there might be something there at 180 degrees opposite as well. I am going to have to slug some barrels and see if I can create a burr like that in a static test.

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.

 

[Buford Boone]

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.

 

[bohem]

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.

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.

 

[Tokay444]

You nailed it, experience is the best teacher.

I forgot, gun smiffin’ is stuck in the stone age of machine technology and theory.

 

[Buford Boone]

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 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?

 

[bohem]

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.