Flame Cutting

[David LaPell]

Ok, this might be a dumb question but here it goes. With flame cutting, I have heard the use of slower burning powders cause it, and some say faster burning powders cause it. So which is it? I don't shoot alot of rounds, (each gun maybe 500 rounds a year). Is there anyway that flame cutting can be avoided in my .357's and .44 Magnum? Both of these guns are over thirty five years old, and my .357 has it a bit worse, but I don't put full house loads in it all the time. (can't say what the previous owner used). The cylinder gaps are both within specs.

 

[Aussie44]

The only way Flame cutting can be avoided is if you don't fire the gun.Flame cutting will only go so deep and stop.Keep shooting and and have fun.

Ken

 

[Leonard]

I thought flame cutting was only a real problem on some of the maxi cartridges 357 etc.

 

[Aussie44]

.357 max eroded the barrels(Forcing Cone Area and the rifling)Accuracy went down hill real quick.Dan Wesson came with an extra barrel and a voucher for another barrel at a reduced price,Flame cutting was not much of a problem,It only goes so deep the stops.

Ken

 

[pownal55]

i find w296 and h110 to be the bad flame cutters in the magnums. i use 2400 now, less flame cut with good velocity.

 

[m1gunner]

One of my revolvers showed what looked like a lot of flame cutting when I first got it. Turned out to be leading and/or powder fouling. After a good cleaning, it was just about all gone, and the forcing cone looked like new as well.

Pleasant suprise for me.

 

[Smitty500Mag]

The weight of the bullet and how hard it's crimped has a lot to do with flame cutting. A light bullet will leave the casing before the powder is completely burned in the casing causing a lot of it to be burned at the cylinder gap. Same thing with the crimp, a bullet that has a hard crimp will stay put longer letting the powder burn in the casing instead of at the cylinder gap.

Smitty

 

[TSQUARED]

As a general rule, the slower powders especially loaded with the lighter bullets will contibute more to flame cutting that the faster powders with heavier bullets.

 

[butchkent]

Smitty's got it.

 

[WR Moore]

I'm not so sure about what actually does the cutting or the cause. I have a model 28 in .357 that went decades without flame cutting. Then I got curious about a box of factory 158 gr JSP Remingtons that I'd bought when I bought the gun and never fired. Cranked off 6 of them. @#$%%^^ I had "flame cuts". I do know that the barrel/cylinder gap does affect the process. And I had reworked the piece to minimize endplay before firing the flamethrowers.

When we issued 681s and 125 gr Federal, we had some pistols that cut badly and some with only minor issues.

 

[Sparks]

.357 max eroded the barrels(Forcing Cone Area and the rifling)Accuracy went down hill real quick.Dan Wesson came with an extra barrel and a voucher for another barrel at a reduced price,Flame cutting was not much of a problem,It only goes so deep the stops.

Ken

We may be off track a bit here. Flame cutting in a revolver refers to the metal erosion of the top strap, just above the f/c. The term is not used to refer to barrel wear to my knowledge. The hotter the ammo, and especially with the slower burning powders, the more flame cutting (of the top strap) there will be. I also cannot think of a reason why the cutting would stop at a certain point, but I'd be interested to hear an explanation to be certain. Now, of course, the hot ammo is going to take its toll on barrel erosion as well. But once again I have never heard that there is a limit to how much erosion can occur.

Of interest to those who own revolvers that have pre-drilled top straps. If the drilled holes are unfilled, they will bounce the cylinder flame backwards and show up as burning marks along the front outside of the cylinder. This process ruins the finish on the cylinder of a blued gun. Solution is to fill the drilled hole directly above the f/c with an allen screw filed flat with the top strap.

Sparks

 

[Aussie44]

Sparks,Read the question before my answer.

Leonard asked - I thought flame cutting was only a real problem on some of the maxi cartridges 357 etc.

My Answer - .357 max eroded the barrels(Forcing Cone Area and the rifling)Accuracy went down hill real quick.Dan Wesson came with an extra barrel and a voucher for another barrel at a reduced price,Flame cutting was not much of a problem,It only goes so deep the stops.

What that says is the 357 Max was a barrel eater and flame cutting was not a major problem,And that the Dan Wessons came with an extra barrel and a voucher for another barrel.

And yes I know what flame cutting is.

Ken

 

[n4zov]

Having actually owned and fired thousands of rounds through one of the infamous Ruger .357 Maximum revolvers, here is my experience. Yes, a very small "cut" appeared in the frame above the barrel/cylinder gap, but it reached a certain point and did not seem to progress any further. I have no idea why this occurred, but it had no effect on the safety or strength of the gun. The flame cutting simply was not an issue nor do I believe it would have ever become one. I did not notice any significant barrel or throat erosion, and the gun maintained its accuracy.

The 10" Ruger was fired in IHMSA competition and loaded exclusively with near max. loads of WW296 and 158-180 grain jacketed bullets. In the Ruger .357 Maximum revolver I believe the flame cutting problem has been greatly exaggerated!

 

[44wheelman]

Top strap cutting will obviously be worse when max pressures with hotter burning powders occur at the barrel gap. What combination of bullet weight & powder burn rate I don't know...that would require lots of time to determine. My brand new 657 was cut pretty quick using max loads of W296 with a 215gr bullet. But once it reached .020 or so deep, it pretty much stopped.

I am sure bullet crimp, powder type, forcing cone profile & finish, chamber throat dia. length & finish, barrel gap, and steel are all factors. Since S&W 357 cylinders are shorter than 44 cylinders, I would guess they are likely effected more.

So to reduce top-strap cutting, shooting lower pressure loads (.38 & .44 specials) would all but eliminate the problem.