flame cutting

[STORMINORMAN]

The number of modern revolvers actually damaged by reasonable reloads are probably less than the number of owners who would ever in their entire lifetime shoot enough unreasonable rounds to damage them...?

Just an IMHO.

Cheers!

P.S. If you are truly worried that a 357 Magnum K-FRAME is going to somehow wear out prematurely, just go ahead and get an L- or N -FRAME.

 

[rwsmith]

Not saying you can't use it....

So... I have 4 lbs H110 and 3 lbs 296. I don't load light weight bullets. How do I use this powder with 158gr lead swc for 38 spl and 357 mag so I don't ruin my guns?
I also shoot 454 Casull 300gr lswc and 44 Mag 240gr lswc. Upon edit I also have a 265gr lswc gc in the 44.

...but H110/Win296 isn't a recommended powder for .38 Special. And these powders do better at max or close to max loads, so I would be inclined to use another powder for .38 Special. Maybe CFE Pistol, Accurate #5 or Alliant Power Pistol.

 

[silicosys4]

bedwards .. I think you'll be just fine with 158 grains bullets. When a bullet base is even with the forcing cone at the B/C gap is when flame cutting would be at its peak. The heavier/longer bullet would delay this "moment" enough for a more complete powder burn within the cylinder/case. At least that's the theory.

This is exactly right, but most importantly, the delay in getting the heavier, longer 158+ gr bullet in motion also contributes greatly in a full combustion, reducing the sandblasting effect of unburnt powder blowing through the cylinder gap and onto the topstrap and across the forcing cone as its deflected off the base of the bullet as it enters the forcing cone.

A 125 gr. bullet is light enough to get moving and through the cylinder into the barrel, with the base of the bullet flush with the forcing cone at a point where there is still unburnt powder being blasted through the cylinder gap with nowhere to go except out through the cylinder gap, against the topstrap and laterally across the forcing cone.
This is when the bullet is still moving slowly, exposing the metal to the blasting effect for the longest. A heavier bullet has more resistance to acceleration therefore a longer delay in that kick out of the case, through the throat, and into the barrel, enough time for a more complete combustion with much less umburnt powder being blasted through the cylinder gap.

coincidentally, this is one reason for a heavy crimp, in addition to resisting bullet pull, a heavy crimp also increases resistance to acceleration and delaying the bullet movement, allowing for a more complete combustion. IMR 4227 is notorious for incomplete combustion without a heavy crimp.

In the case of flame cutting, its the unburnt powder particles that do all the damage.

 

[rmc]

Heavy charges of ball powders coupled with light bullets are the combination to avoid.

AGREE!! I picked up a Ruger 357 Maximum at a very good price because the owner was reloading 110 and 125 grain bullets with fast powder. The flame cutting had reached it's max depth but the owner thought he made the gun unsafe and wouldn't shoot it any more. Slow powder and 180 to 200 grain bullets and I now have an accurate long range shooter.

 

[rockquarry]

Sadly 2400 is gone.

Got lucky, I guess, but found an 8 lb. jug about two weeks at Powder Valley.

 

[Nevada Ed]

The K frame cracks and throat erosion seemed to be greatest with light bullets, 110 & 125 gr, and ball powders. The worst problem seems to be when the bullet has passed through the throats. Delaying that millisecond by using longer bullets, [heavier] seems to be the answer. I consider 240 gr bullets to be light in 44 magnum. Staying heavier than that gives the bullet a longer time to pass through the forcing cone and allows the powder a more complete combustion.

I will add that a K frame will also crack from powders that are NOT
a ball type, .......... namely Unique, since I never had 2400, until the 90's, and with loads from manuals.

 

[71vette]

bedwards .. I think you'll be just fine with 158 grains bullets. When a bullet base is even with the forcing cone at the B/C gap is when flame cutting would be at its peak. The heavier/longer bullet would delay this "moment" enough for a more complete powder burn within the cylinder/case. At least that's the theory.

You are also using less powder with a 158 vs a 125. Another factor.

 

[Forrest r]

As others have stated, flame cutting of the top strap is a non-issue. It happens & I'm sure it will eventually affect a revolvers frame. The round count would be astronomical.

Again, as others have stated, ball powders and sanding occur. Hotter burning powders like bluedot, powder pistol, lil-gun, titegroup, etc. will flame cut faster than powders like clays or ww231 for example.

At the end of the day it really doesn't matter what you use/shoot. Your revolver is going to need have the bbl setback and a new forcing cone cut. The timing of that revolver will need rebuilt at the same time.

My own experience:
I shoot a mix of standard 38spl reloads (bullseye or clays/158gr cast). 38spl p+ (any medium burning powder/158gr) and 357mags that are a mix of fast burning powders, medium powders and mag/ball powders. This is a bbl out of a 586 that had +/- 75,000 rounds ran thru it since it's last rebuild (2x rebuilds prior).

Has the typical flame cutting with the majority of it at the 12 o-clock position.

It's nothing more than the price of doing business

 

[Chuck Edwards]

comment confirms what ive been reading in other places, so listed data, the faster powders would have smaller charge weights like say titegroup? and probly need to confirm against a chart?..thanks

Be careful with Titegroup. I burned a nice trench across the top strap of my 27-3 with a thousand rounds of a max load of it in .357 brass under 125-grain LFPs. I was trying to get a lower-recoiling full-power load and it kinda worked but the juice wasn't worth the squeeze. The problem stems from the fact that Titegroup is an extremely hot-burning powder, plus the use of short bullets as mentioned above. All my .357s now live on a diet of 158-grain ammo.

Titegroup works okay as a powder for .38 Special - I went through several thousand rounds of 158-grain +P-level loads using it when I was an active IDPA competitor. The 67-1 I used showed no ill effects from those loads, but the cylinder got hot enough practicing reloads that I switched powders.

 

[STORMINORMAN]

"Life (barrel?), on this the third planet from the sun, is for most carbon-based life forms distributed on a bell-shaped curve..."

You have your "+/- 75,000" rounds (per rebuild!) firearms and you also have those multiple revolver owners (as in: owning more than one) who will never shoot 1,000 rounds of magnum ammunition in their entire life!

And the twain need not ever actually meet? (With apologies to R. Kipling!)

Cheers!

P.S. I'm hoping I live long enough to unintentionally wear out a barrel in a modern revolver...

 

[stansdds]

As others have stated, flame cutting of the top strap is a non-issue. It happens & I'm sure it will eventually affect a revolvers frame. The round count would be astronomical.

Again, as others have stated, ball powders and sanding occur. Hotter burning powders like bluedot, powder pistol, lil-gun, titegroup, etc. will flame cut faster than powders like clays or ww231 for example.

At the end of the day it really doesn't matter what you use/shoot. Your revolver is going to need have the bbl setback and a new forcing cone cut. The timing of that revolver will need rebuilt at the same time.

My own experience:
I shoot a mix of standard 38spl reloads (bullseye or clays/158gr cast). 38spl p+ (any medium burning powder/158gr) and 357mags that are a mix of fast burning powders, medium powders and mag/ball powders. This is a bbl out of a 586 that had +/- 75,000 rounds ran thru it since it's last rebuild (2x rebuilds prior).

Has the typical flame cutting with the majority of it at the 12 o-clock position.

It's nothing more than the price of doing business

Most shooters will not fire 75,000 rounds in their lifetime, much less through just one firearm.

 

[243winxb]

S&W 44Magnum 29-2 Barrel set back in 2018.

Another thread got me to thinking(I know dangerous)
Are some powders more prone to flame cutting than other powders? I load 44 mag with H110 and I know the muzzle flash is a big ball of fire.
I don't shoot whimpy loads and like ringing steel at 100 yrds. I am happy with H110 but if theres a better powder with less flame cutting that would make the revolver happy too.

My 29-2 had the barrel set back by S&W when it was sent in for the cylinder rotating backwards. Got all new springs also.
Cost less then $200. Used H110 & 296 with 250 gr home cast.

Takes many years of use to burn out the forcing cone.

[

Photo after barrel set back. Barrel should have been replaced, but this one is Mag Na Ported.