To flute or not to

[Eddie Harren]

"Now to the idea of bottom ports..."

This is one situation we all have in common!

 

[rifleman700]

thanks, I think. If a computer simulation says so, like everything on the Internet; it must be true. Of course, scientists also proved that Bumblebees are too unaerodynamic to fly.

I stand by the only empirical data produced. That by Savage 25 or so years ago. This would be a good time for someone to fit, chamber, and headspace barrels to an action; then fire them. Then flute without removing the barrel from the action and retest.

Since that is not likely, all we have is conjecture and opinions. That, and the fact that it costs well over $100 to flute a barrel weighs heavily in the process.

I could very well be wrong, I've been married twice, so my judgment is occasionally suspect.

Now to the idea of bottom ports...

If you want testing / documentation, buy Bryan Litz's latest book MAILRS. It all there with plenty of data.

 

[FrankLD46]

I am in the process of making the list for my new build for GA Precision to build me a 6.5 Creedmoor. It will be the Crusader with a 26 inch barrel and 1:8 twist. Fluting will help reduce weight and have not made a decision. Will fluting reduce stiffness and rigidity and reduce accuracy at long range? Opinions is appreciated

if the barrels any good and smithing done right fluting will not hurt accuracy blieve it or not fluting came about because of us benchresters wwho fire so many rnds so quickly [at times] and needed the barrels to cool down quickly thats all it wass designed for barrel cooling

 

[FrankLD46]

I've built a couple of 7mm Rem Mags with 10-fluted Kriegers that shoot really great groups for their owners - and they look neat, which I've always thought was one of the reasons people really wanted the flutes in the first place.

OTOH, I ordered in a factory fluted Krieger 6.5mm blank in medium Palma contour for another customer several years ago, then wound up buying it back from him when he ran into $$ problems. I chambered it in 6.5x47, fitted it to a trued M700 in a laminated wood copy of the McM A5, and proceeded to try to find a good load for it. That SOB turned out to be one of the pickiest bbls I've ever chambered - I found exactly one load that shot acceptably well out of it.

Right now, I've got a Howa long action out in the shop that I fitted a Krieger in 280 AI for. The blank was ordered in as a #5 sporter, but when I opened the box, it turned out to be a #6 sporter, which is considerably heavier than I wanted. I've been thinking about sending it out to one of the shops I trust that specializes in fluting bbls & bolts, and having them do the 10 flute pattern that Krieger offers in an effort to reduce weight - may go ahead with the plan, since I doubt seriously that I'll ever be able to sell it as-is. Should do some shooting with it before to establish an accuracy baseline, then I'd have an idea whether the fluting hurts accuracy or not.

 

[FrankLD46]

i have had fluted and regular barrels and have had excellent acc from both kind i would not turn flutes on a barrel without consulting a reputable gunsmith mite set up stress in your barrel

 

[M14AMU]

You guys may as well admit that if a winner uses the lid of a commode for a rest.....there will be a shortage of commode lids!!

 

[LHSmith]

The lesser the barrel metal- the quicker it heats up. The more barrel metal-the longer it takes to cool down. Pick your poison as it's a catch 22 thing.

 

[IdahoSharpshooter]

so, increasing the surface area by 30-50% will not keep the barrel any cooler, or cool it off any faster...?

I went out to the garage to look at my HD. It is air cooled, and has fins on the cylinder head and cylinders. HD says they are there to "significantly increase the cooling rate and increase (speed up) thermal (heat) transfer from the combustion chamber and pistons". Sounds like cooling the way I read it.

I also popped the hood on my car. The radiator has cooling fins. Why?

Anybody here got an air cooled motorcycle? Got fins?

 

[LHSmith]

so, increasing the surface area by 30-50% will not keep the barrel any cooler, or cool it off any faster...?

I went out to the garage to look at my HD. It is air cooled, and has fins on the cylinder head and cylinders. HD says they are there to "significantly increase the cooling rate and increase (speed up) thermal (heat) transfer from the combustion chamber and pistons". Sounds like cooling the way I read it.

I also popped the hood on my car. The radiator has cooling fins. Why?

Anybody here got an air cooled motorcycle? Got fins?

And if you paint the fins flat black, you'll increase it's efficiency by 0.05%. It's a duration (time thing) that prevents one from using that analogy. One thing I do know for certain is in Benchrest I don't want my barrel to heat up quickly.......I want to fire a shot or two to warm it up...then I want the barrel temp. to remain as constant as possible ( i.e.= minimize delta T) in an attempt to minimize variables. With current barrel contours and non shooting time in between relays, cooling is not a problem until it gets above 90' at which point a damp towel on the barrel works fine. I am sure fluting has merits in other disciplines.

 

[dkhunt14]

I could very well be wrong, I've been married twice, so my judgment is occasionally suspect.

Now to the idea of bottom ports...

They actually have them, called drop ports. Reliable ejection on cases that are known to be hard to eject. Also no pressure from an ejector pin trying to push a case sideways. Matt

 

[Tempest]

I built my son a new FTR gun for his graduation present. I had the barrel fluted honestly because it looked cool with the paint scheme I chose for it. Hope it shoots!

 

[IdahoSharpshooter]

I read Litz's chapter on fluting. I am not sure two fluted barrels means diddly. The only thing those two barrels have in common is chambering. If he got twenty barrels from one maker, fitted, etc, them one at a time to an action, then shot ten five shot groups under controlled conditions; then fluted them all the same way, then shot ten five shot groups under identical conditions, it would be such a small sample group that no one would put their professional reputation at risk by publishing a paper to be read in a peer journal claiming anything beyond the fact that barrels seem to warm up as the number of groups fired increases.

The report would read like Litz, where he quotes Harold Vaughn "Most of the experts SEEM TO THINK that fluting doesn't help." Litz then says that he (Vaughn) doesn't provide any context or data in the book to help us understand what led him to say that. That means, in court, that is just and only Vaughn's opinion. Litz then bases his opinion, not based on any scientific data, just POI shift sampling on TWO barrels, that fluting may be an issue. Since one barrel's POI was twice that of the other, which barrel provides valid data?

His findings have the same validity as a car magazine testing a red Hellcat, and then a blue one, and claiming, since the blue one ran a faster quarter, that painting a car blue will increase performance over painting it red.

If you had a life threatening disease, and there were two treatment options; would you choose one method of treatment over based on the same two sample criteria?

In the end, to flute or not comes down to preference, since we have no clear winner as to accuracy.

Rich

PS: Tempest, that is a gorgeous rifle. Who did the fluting, if you do not mind sharing?

 

[Tempest]

Thanks! One of those few times in life, something actually turned out better than you thought it would. The paint turned out killer. Benchmark did the barrel. Very happy with the end result.

 

[rifleman700]

Am I missing something here? Who is saying that fluted barrels are junk? The conversation is do the flutes actually have a real world advantage other than weight compared to a standard barrel.

If two barrels tested is not a large enough sample then what makes 20 better? Where is it written that 20 is the magic number. This kind of talk can go on and on. There will always be somebody that wants more samples because they are unwilling to concede a data point.

If you were to figure the deflection percentage difference between the heavy palma bbl and the fluted heavy palma bbl tested I would bet that the percentage of material removed would be the same. More material less deflection.

I would not hesitate a moment to use a fluted bbl again but it would be for weight purposes only.

 

[M14AMU]

Rifle Smiths love fluting! It turns into $$$$$$$$$$$$!!

 

[Mr.Knowit all]

I read Litz's chapter on fluting. I am not sure two fluted barrels means diddly. The only thing those two barrels have in common is chambering. If he got twenty barrels from one maker, fitted, etc, them one at a time to an action, then shot ten five shot groups under controlled conditions; then fluted them all the same way, then shot ten five shot groups under identical conditions, it would be such a small sample group that no one would put their professional reputation at risk by publishing a paper to be read in a peer journal claiming anything beyond the fact that barrels seem to warm up as the number of groups fired increases.

The report would read like Litz, where he quotes Harold Vaughn "Most of the experts SEEM TO THINK that fluting doesn't help." Litz then says that he (Vaughn) doesn't provide any context or data in the book to help us understand what led him to say that. That means, in court, that is just and only Vaughn's opinion. Litz then bases his opinion, not based on any scientific data, just POI shift sampling on TWO barrels, that fluting may be an issue. Since one barrel's POI was twice that of the other, which barrel provides valid data?

His findings have the same validity as a car magazine testing a red Hellcat, and then a blue one, and claiming, since the blue one ran a faster quarter, that painting a car blue will increase performance over painting it red.

If you had a life threatening disease, and there were two treatment options; would you choose one method of treatment over based on the same two sample criteria?

In the end, to flute or not comes down to preference, since we have no clear winner as to accuracy.

Rich

PS: Tempest, that is a gorgeous rifle. Who did the fluting, if you do not mind sharing?

I disagree with you that there was no data bc he used POI and Temp of the barrels and that IS some data. Do you have any data supporting fluting?? Any? I haven't seen a test anywhere supporting barrel fluting. I have heard great grounds for it but in the end no empirical data. But you are correct that 2 barrels is VERY small amount of data and I don't think an accurate account could be drawn from this test but it is a start even if it doesn't hold much validity. I think Litz even wrote that somewhere in that chapter.
Accuracy International posted a study that they did and why they stopped fluting their barrels. I believe it was in one of the Sniper magazines from a few years back. You may want to read it.

As I said before... There are a lot of VERY sensitive shooters on here. Someone bad mouths a scope, barrel co., action, bullet, etc... another shooter has had good luck with and it's on!! I don't think anyone is saying that your gun won't shoot if it's fluted but that the benefits may not be as good as we were once told. JMO

 

[jmatters]

if the barrels any good and smithing done right fluting will not hurt accuracy believe it or not fluting came about because of us benchresters who fire so many rnds so quickly [at times] and needed the barrels to cool down quickly thats all it was designed for barrel cooling

My experience is with 2 different rifles. One is a Tube gun the other a conventional configuration.
Barrels are identical, same mfg., same profile, same length, chambered by the same smith, same reamer. The fluted barrel cannot keep up with the non-fluted one.
The fluted is attached to a BAT action, jewell trigger with a NF fixed 42 Comp. It shoots about 3" at 600.
The unfluted is on a PAS action (now Time Precision), with a Shilen(?) trigger and a NF 15-55 comp. It has shot 2" and under.
Same match; different relays.

Maybe its the randomness of barrels, but I offer the experience here for what its worth. I won't use a fluted barrel on a comp gun again.
Your mileage may vary.

 

[JRS]

I read Litz's chapter on fluting. I am not sure two fluted barrels means diddly. The only thing those two barrels have in common is chambering. If he got twenty barrels from one maker, fitted, etc, them one at a time to an action, then shot ten five shot groups under controlled conditions; then fluted them all the same way, then shot ten five shot groups under identical conditions, it would be such a small sample group that no one would put their professional reputation at risk by publishing a paper to be read in a peer journal claiming anything beyond the fact that barrels seem to warm up as the number of groups fired increases.

The report would read like Litz, where he quotes Harold Vaughn "Most of the experts SEEM TO THINK that fluting doesn't help." Litz then says that he (Vaughn) doesn't provide any context or data in the book to help us understand what led him to say that. That means, in court, that is just and only Vaughn's opinion. Litz then bases his opinion, not based on any scientific data, just POI shift sampling on TWO barrels, that fluting may be an issue. Since one barrel's POI was twice that of the other, which barrel provides valid data?

His findings have the same validity as a car magazine testing a red Hellcat, and then a blue one, and claiming, since the blue one ran a faster quarter, that painting a car blue will increase performance over painting it red.

If you had a life threatening disease, and there were two treatment options; would you choose one method of treatment over based on the same two sample criteria?

In the end, to flute or not comes down to preference, since we have no clear winner as to accuracy.

Rich

PS: Tempest, that is a gorgeous rifle. Who did the fluting, if you do not mind sharing?

That so called testing was performed by the "experts" at PRB, and Litz stated what he was told by the PRB clan

 

[JRS]

From Dan Lilja:

"We've been asked if machining flutes into a rifle barrel causes stress in the steel. The short answer is no, it does not. To the contrary, fluting can and will relieve stress if it is already present. The same is true of any outside machining work performed on a barrel".

 

[nakneker]

Half of my rifles have flutes, half do not. They all shoot under a half inch or they get sold. I love the looks of the various types of fluting and haven't seen any negative effects with many different rifles.