Gunsmithing SH Visits Bartlein Barrels, Part Two: Rifling Machines

[Lowlight]

Here is part two of our multi part interview and look at Bartlein Barrels,

They let SH go behind the scenes and actually document their barrel making process. This includes looking at the machines and the programs that control the rifling.

Bartlein Barrels Rifling Machine - YouTube

Enjoy,

 

[Jeff in TX]

I can honestly say I've never seen a barrel rifled before. I've read a lot on the subject over the years but had never witnessed the machining process and in my mind had formulated a vision of how I thought it was done. After watching the video I have to say what I had pictured in my mind was nothing near how it's really done. Great set of video's and interviews guys, I've learned a ton from them.

 

[TimeWillTell]

Very interesting video, I'm learning a lot from these! I know it depends on certain factors, but on average how long does it take to rifle each barrel?

 

[RobertB]

Awesome. I've always wondered how the cut rifling and progressives happen. Nice to see it. I love the product bartlien puts out.

 

[Boxcar]

Nice to see how far advanced modern day machines are, compared to the old Pratt & Whitney machines that are so coveted.

 

[Frank Green]

Very interesting video, I'm learning a lot from these! I know it depends on certain factors, but on average how long does it take to rifle each barrel?

TimeWillTell, Depends on several things such as.....the length of the barrel, the number of grooves, the depth of the grooves and even things like tooling and the steel etc....but the biggest influence normally are the first three things.

A 5 groove barrel takes longer than a 4 groove. Same as a 6 groove takes longer than a 5 or 4 etc.....

The fastest I've seen barrels done in time wise has been about 30 min. from a rifling point of view only. We've done barrels like this in 4 groove, .224cal. type barrels and even .30cal. 4 groove barrels etc...the longest it's taken us has been 10 groove, 20mm cannon barrels and those were 53" long and the groove depth in each groove was like .020" deep. That's like rifling eight .30cal. barrels at one time. Those took like 12-14 hours (they didn't cost $300 either but they are the nicest 20mm barrels on the planet!)

An average time I would say about 1.5 hours.

Yes you can speed things up and get them done faster by changing things like the cutting speed, return feed rate and how heavy of a cut you take but we are more concerned about the finish and quality vs. how fast we can get it done.

I know back around WWI and WWII 5 groove .303 Enfield barrels they were single point cut rifling them also. Each cut they took out .001" per pass. We are only taking out .0001"-.0015" per pass. So if those .303 Enfield barrels had a .004"-.005" deep groove you only had to take 4-5 cutting strokes per groove and it was done. Doing it .0001" to .0015" per cutting stroke you just multiplied the time frame by almost 10x but they're were not necessarily concerned about the finish in the bores either. It was about getting a stick into a soldiers hands as fast as possible.

Later, Frank
Bartlein Barrels

 

[Jhnmdahl]

Frank - thanks for sharing all the info lately. I'm curious about the machines you use - are they all custom machines, or is somebody still producing cut rifling machines commercially? Looks like a pretty nice setup.

John

 

[Boxcar]

Precihole still makes button and cut rifling machines. I don't know what brand machine Bartlein uses though. But there's still a few company's that make them.

 

[jugi16]

Frank

Is the blank barrel set up similar to the chambering process or does run out even matter when making longitudinal cuts? I assume it does. Thanks for the videos Lowlight.

 

[Frank Green]

Frank - thanks for sharing all the info lately. I'm curious about the machines you use - are they all custom machines, or is somebody still producing cut rifling machines commercially? Looks like a pretty nice setup.

John

Custom machines that Bartlein Barrels built.

Later, Frank

 

[Frank Green]

Frank

Is the blank barrel set up similar to the chambering process or does run out even matter when making longitudinal cuts? I assume it does. Thanks for the videos Lowlight.

Not to sure about your question but just like the P&W rifling machines the rifling head follows the bore there is no real run out/set up issue. Chambering is different as far as the set up goes.

Later, Frank

 

[jugi16]

Not to sure about your question but just like the P&W rifling machines the rifling head follows the bore there is no real run out/set up issue. Chambering is different as far as the set up goes.

Later, Frank

That answered my question.

 

[Slug-O]

Great video and thank you for making them. I got my Bartlein in the mail today. Cant wait to get my rig finished..

Slug-O

 

[Lowlight]

I am glad everyone is enjoying them, make sure you pass them along and share the links ... It helps bring attention and opens up the door for us to do more.

I have a few more segments to do, I have the Pre & Finish (hand) Lapping videos to do, as well as the full Rifling Tool video, so there are at least 3 more.

 

[jbell]

I am glad everyone is enjoying them, make sure you pass them along and share the links ... It helps bring attention and opens up the door for us to do more.

I have a few more segments to do, I have the Pre & Finish (hand) Lapping videos to do, as well as the full Rifling Tool video, so there are at least 3 more.

Ya, stuff like this is great for us "common folk". It really helps us connect with the people who we do business with. It also educates us on the processes and helps develop a deeper respect for the craftsman who support our passion. I know these videos will help promote the manufactures who you visit and also help support the Hide (both of which are great!) but for an end user who may only talk to the people over the phone or via email it takes it to a bit more personal level. Good stuff for sure!

 

[Jrb572]

Do you drill the initial hole in the barrel also? Or do the blanks come with some size hole already drilled in them?

 

[Lowlight]

They drill the initial hole, the blank stock is visible in the video, and the Pratt machines in the first video drills the hole. The bit I have in my hand in part of the first video is a .50 cal drill bit.

 

[oldfatguy]

What? No old guys with leather aprons? Great to see their shop and that they are taking advantage of the latest 'puter controlled machines.

Thanks for the videos, great job, keep them coming. On the downside the waiting period will probably increase.

OFG

 

[Frank Green]

I want to say THANKS to Frank Ga. for coming and seeing the shop and doing the video's from all of us here at Bartlein! Frank talked about coming here and doing it and over time we struggled with letting any pictures or video's being shot here.

We didn't do it or ask Frank Ga. to do it to promote or company or to do it to get more work in any way shape or form.

We're glad everyone is enjoying the video's and hopefully it opens the average persons eyes into how some barrels are made and the time it goes into them etc....any maybe to dispel some myths about barrel making, cleaning etc...all though I know it raises questions as well but all in all I feel it's been a good thing.

Thanks again Frank Ga. and SH!

Later, Frank Gr.
Bartlein Barrels

 

[Frank Green]

Here is part two of our multi part interview and look at Bartlein Barrels,

They let SH go behind the scenes and actually document their barrel making process. This includes looking at the machines and the programs that control the rifling.

Bartlein Barrels Rifling Machine - YouTube

Enjoy,

Gotta say that's my buddy Todd! Has learned a ton since he started here and is one of the best guys to boot! Not afraid to ask questions so he understands things and always trying to make things better! He's good people!

Later, Frank
Bartlein Barrels

 

[buckey]

Did Lowlight buy you Bartlein Boys a few beers??

 

[STR]

Really enjoyed the videos! Thank you.

 

[skeetlee]

What type of control do you have over the barrel steel you receive? Im sure you have certain specs you request from your supplier. Reason I ask, is that over the years while using your great barrels I have noticed some barrels have seemed to cut a little different than some of the other times ive used your barrels. I chamber quite a few of your barrels for personal use, as I am always looking for that ppc hummer barrel. Some barrels seem to cut a little smoother than others. I have always just assumed it is the difference in the steel? I will say I can not see one bit of difference in accuracy no matter how the steel cut. All have been competitive.
question 2- why so much interest in a 5r barrel? With my ppc 6mm barrels 4 groove have always seemed to shoot better. what am I supposable missing? I know of several riflemen that will not shoot anything but a 5R and I just don't understand it? Thanks a bunch Frank! Lee

 

[Frank Green]

What type of control do you have over the barrel steel you receive? Im sure you have certain specs you request from your supplier. Reason I ask, is that over the years while using your great barrels I have noticed some barrels have seemed to cut a little different than some of the other times ive used your barrels. I chamber quite a few of your barrels for personal use, as I am always looking for that ppc hummer barrel. Some barrels seem to cut a little smoother than others. I have always just assumed it is the difference in the steel? I will say I can not see one bit of difference in accuracy no matter how the steel cut. All have been competitive.
question 2- why so much interest in a 5r barrel? With my ppc 6mm barrels 4 groove have always seemed to shoot better. what am I supposable missing? I know of several riflemen that will not shoot anything but a 5R and I just don't understand it? Thanks a bunch Frank! Lee

Lee, Type of control over the steel. This is the biggest thing a barrel maker I'm going to say has no control over. We don't make it. Even though we work with mill closely and want the steel made to the same recipe etc....it still can vary a little from lot to lot. Sometimes the different alloys etc...will vary a tad up or down. They basically have a tolerance range like anything being made. Same goes for heat treatment and stress relieving of the steel. We start with heat treated and double stress relieved material. We ask for a 30rc on the hardness but again they have a tolerance range. I want to say it's 4 points if my memory is correct. So it could come in at 28rc or as high as 32rc. We've made barrels for testing and some for customers with a rc as low as 27 and as high as 35. For the most part I don't see the hardness effecting the way the barrel shoots at all but as you pointed out a slightly different mix in the alloys, hardness etc...can make them machine a little differently from time to time. We do check our steel for hardness when it comes in with a RC tester and the shipment has to have the material certs. as well so we can look at the chemistry/mix etc...we can always send it to a lab and have it checked if we have any concerns on anything.

Also as you know the type of cutting oil you use, is your chamber reamer new or has it been used in X amount of barrels can make it cut differently. Also the relief angles on the cutting edges of how the reamer is ground can make it cut differently in the steel as well. Sometimes a customer thinks he is having a hard time with his reamer and the way it's cutting but it can be the way it was ground.

The difference in the number of grooves? First off I will say the number of lands/grooves or the style of rifling being used to me doesn't really mean anything when it comes to accuracy for the most part and I do have a but here and it's with 6mm in particular. A guy shooting/building a 6PPC benchrest gun I will say only use standard rifling (what we call English/Whitworth style rifling. This is where the lands basically meets the groove at a 90 degree corner) and don't use the 5R style rifling. Why? I feel those short jacket 6mm bullets that those guys use which are mostly in the 65-68gr. range have a short bearing surface. I feel the standard rifling bites them better and drives them better. If you build a 6PPC benchgun with a 5R style barrel I'm going to say on average you will get a gun that will shoot in the high .2's to flat .3's but nothing better. Now take the standard type rifling and we've made 3 groove, 4 groove, 5 groove and 6 groove and even 8 groove barrels I don't see a difference in the way they shoot smaller groups/agg's then the 5R will. I've got a standard 5 groove on my gun. It averages in the mid .1's if I do my part. It was also independently tested in a controlled conditions (test tunnel) and it shot some groups in the '0's and shot mostly in the low to flat 1's. Even though we only see it with the 6mm caliber I do apply this logic to a .30BR shooter and say a .224cal. shooter shooting the lighter weight bullets as well.

Now take another 6mm being used as a long range gun and it's built in 6 Creedmoor but that shooter is shooting 105-108gr. bullets. Those long bullets it seems the 5R style rifling doesn't bother them. My 6 Creedmoor with Berger 105 hybrids or 105 Hornady BTHP has shot 1/2" groups off the bench at 200 yards. I do feel the 5R style rifling with the gentler angles on the sides of the lands and the odd number of grooves (the lands don't directly oppose one another) distorts/upsets the bullet jacket less and helps fight bullet failure which is more of a problem for a long range shooter than a short range shooter. Bullets can fail because of thinner jackets, lot to lot variance and how they're made, damage to the barrel from cleaning or from when it was made, rougher throats from wear/high round count, twist rates and higher velocities. Any one of these things can be a cause or work against one another and cause failures also.

There is an old saying if you want hardcore accuracy go with standard/conventional type rifling and to an extent I agree but when a guy ask me this question as to what to use my first question back is what are you using the gun for? Then go from there before I recommend a 4 groove or a 5R style barrel.

Later, Frank
Bartlein Barrels

 

[ridgeway]

Good questions Skeet... thanks for the detailed answer Frank.

Frank,
Have you ever refused a shipment of steel that did not meet your requirements?

 

[agbm]

Great info, now the video has me thinking about ordering a gain twist/ left hand twist barrel!!!!

 

[Frank Green]

Good questions Skeet... thanks for the detailed answer Frank.

Frank,
Have you ever refused a shipment of steel that did not meet your requirements?

Yes. The mill skipped a operation in the manufacturing process of the steel. The problem was nothing that we could check/test etc...but it showed up during the rifling process. There were no safety issues with it etc...but it was beating up our tools like no tomorrow. We returned the whole lot of steel. The mill replaced it but wouldn't cover our lost labor which came to around $55k and the time it set us back!

So now when we get a new lot of steel will take a couple of pieces and rush them thru the shop and test everything to avoid any headaches down the road! Live and learn!

Later, Frank
Bartlein Barrels

 

[jackinfl]

From an end user stand point this whole back and forth is awesome. From Frank's videos to Frank Green answering questions in depth.

This is much appreciated.

 

[Unknown]

Amazing stuff, and very cool that Bartlein would take the time to educate us. That is some really classy public service to people who aren't even necessarily customers...(yet). It is much appreciated. Thank you.

 

[fiveoshooter]

Excellent video - nice job. I had Al Warner install 5R barrels on our issued R700 .308 duty sticks and they are shooters. Outstanding barrels.

 

[matthias]

very cool to see their shop. thanks for the videos

 

[skeetlee]

Thank you frank for your time. Much appreciated!! Lee Gardner


Actually I would like to thank both franks here for there time and effort.

 

[SFC Carpentier jr]

GREAT job Frank. Enjoying how these barrels are made.