S&W’s new EDM barrels seem to lead very bad due to the design with the rounded rifling. Marlin rifles get complaints for the high twist rate they have. I’m sure there is more to this, but is this the future even if the EPA doesn’t get us??? Is casting going to become like shooting BP as fewer are into it each year???

the non lead compliant barrel thing has been with us since the early 1900's. at least one of the prototypes of the 1903 springfield had such a barrel which was rumored not to be able to meet mil specs for longevity.
I think it boils down to production rate where alternate forms of rifling are being employed.
They seem to claim velocity gains with such schemes, though I have yet to see any real world difference. In fact my 1911A1 Springfield exceeded a USP with polygonal rifling by an average of 20 FPS using factory ammo out of the same box.
Looking at the bores from a machinists point of view, I can see where a tool would have better service life when forming such rifling.
In the case of EDM methods its even more tempting since its an arc that does the work. I suspect that a barrel rifled with EDM methods would have a coarse surface rather than a burnished one afforded by traditional tooling. Perhaps with a little time at the bench with some slugs and lapping compounds, an EDM barrel just might find some redemption.

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it just needs more voltage

Also, there is the issue of the wrong alloy/lube/diameter for the wrong purpose and caliber. It is a balancing act with all the factors to keep the leading down. Low velocity target rounds seem to suffer terribly for alloy that is far too hard. Everyone thinks "hard cast" is the way to go and buy hard, incorrectly sized/lubed bullets for their firearm and wind up wondering why they have terrible leading problems.

Slug your barrel and chamber throats, check the bullet diameter and hardness, get the right load data and adjust everything as necessary.

I have some of the new revolvers that have EDM barrels and shoot cast just fine- but then I push them moderately and keep the alloy soft, and had a local 'smith ream the cylinder throats.

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Lost it all in a boat accident

I don't think S&W is intentionaly trying to steer anyone away from lead bullets. It's just a by-product of their trying to manufacture their guns as cheap as they can to make a higher profit margin. It's the new age business ethic as opposed to the old one of making your customers happy.

I don't mean in any intentional way this is being done. I just mean this may be the way of the future for one reason or another. Or I guess they could be doing it at the request of ammo companies. These days nothing surprises me much any more.

nah ... its a function of tooling
EDM requires an electrode which involves lower cost than a tungsten carbide button or similar cutter which has a very limited service life.
In EDM its a chunk of tungsten that need not be sharpened or even be all that precise and gives a greater service life at lower replacement cost

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it just needs more voltage

Huh! I shoot lead in late model S&Ws and Marlins. Had no idea I was supposed to be having problems.

In Lee's manual for reloading, Mr Lee writes of a way to calculate the hardness of your bullet to match it to a chamber pressure to lessen leading and increase accuracy. Included are several pages of load recipes to help find a load that works best.

Very fascinating.

The bullets used may have to be a bit harder cast with this rifling.

I'm a total Noob at this, but I've just finished reading four reloading manuals back to back and I slept at a Holiday Inn last night

You need to take a look at S&W's ECM barrels sometimes. The best description I've seen for barrels with this type of rifling is that they look shot out and over polished. Because you won't find a sharp corner and the surface finish approaches the smoothness of glass. I suspect that exceptional smoothness is the reason why they don't do well with lead bullets, it's so smooth that it won't properly "wet" with common lubricants.

I've also seen some postings by re-loaders who claim that their ECM barrels don't lead up with their home brew ammo. However, I have yet to see one of them reveal what they are using to lubricate their bullets. Quite simply, with the correct lubricant it may be possible to shoot lead in these barrels, however I don't know the secret. Until I find out that secret, I'm only using jacketed ammo in my ECM barrels.

For me, that really isn't a problem. I don't reload at this point and after looking into the cost involved in reloading jacketed ammo don't see enough benefit to spend the money for a reloading setup. However I am saving my brass in the event that 38 spl. gets even more expensive or the price of FMJ in bulk goes down.

I'm also curious about the possible velocity benefit of the ECM process. Based on appearance alone, it certainly looks like an FMJ bullet will slide down an ECM barrel with less friction than the older style cut rifling. I'm curious enough that at some point I may actually purchase a chronograph. Both my 67-1 and model 620 have identical B/C gaps at 0.006 inch so there may be some validity in comparing the results from each gun shooting FMJ.

As for the accuracy of the new process, my 620 is simply stunning when I mount a scope on it and shoot it from a rest. I also have a 6 1/2 inch 610-3 with an ECM barrel that I've done fairly well with using a reflex sight at 35 yards, discount the one flyer and with 40 caliber Federal I've shot it to 2 1/4 inch in my best effort to date. At some point I'll mount my scope on the 610 and try it at 50 yards, however it's going to take more practice because I've already found that longer barrels require better recoil management skills than I have at this point. While my best with the 610 is 2 1/4 inches, the average at 35 yards runs around 4 inches.

I bought the Wheeler fire lapping kit years ago and fire lap every new gun I buy.

I shoot cast almost exclusively and have very little problem with lead build up.
When I do get some buildup I use an Outers electronic Lead remover. By the time I clean the next one in line the offending gun is clean too.

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Shoot fast & live long
Warren

Another good reason to buy only old guns!

The EDM barrel in my .44 Special would have horrendous leading with lead bullets. I tried different alloys, lubes, and commercially made lead bullets. Nothing helped. Then I bought some copper-plated lead bullets from Xtreme Bullets. Problem solved. Now I shoot some plain lead bullets, and then shoot some copper plated bullets.

you also must take into account metallurgy
the old world way promoted work hardening and an alignment of the grain structure. EDM leaves the steel "raw" in this regard as the process has a penetrating effect more than a longitudinal cutting or pressing effect

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it just needs more voltage

I was just wondering does S&W use EDM that uses a graphite electrode that the edm machine rotates the electrode as it goes through the barrel or do they do it with a wire edm machine I have seen some wire edms that can jut about do anything, just wondering which one they use. Jeff

There is one thing to note, as of just three years ago, not all barrels on all guns were EDM cut. When I toured the plant then, women were still cutting rifling on some revolver barrels on old oil bath rifling machines. I believe they were model 25 or 29 barrels. That may have changed by now.

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Lost it all in a boat accident

I have been shooting Hornady HBWC's in my 620 and did not know I was giving up accuracy. Maybe the soft swaged bullets are the key but if it shot any better I would be impossible to live with.

I don't see pressure from any one manufacturer, but undoubtedly there IS pressure to get rid of lead from several quarters. I think it's another way in many that shooting is going to become more and more difficult to enjoy and become more of a PITA to be a gun owner/shooter. What does bug me is that I think that the ammo/gun suppliers will fall in step with the EPA and cave in to public pressure and be 'proactive' in making lead obsolete even if performance suffers.

Lead????

With what I have been paying for bullets recently, I am certain that they are made of silver, palladium or rufenium.

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Gunner, Sabot Up!

Ruthenium, actually.

Rufenium being the Southern colloquial spelling

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Gunner, Sabot Up!

Rufenium is any room in your house that has a rufe.

H'YUK H'YUK H'YUK

I wonder if this is also part of the upcoming "lead free" laws some legislators are looking into. It would not surprise me if Obama or one of his ilk now that the gun ban went down like the Hindenburg are looking into this very thing. Again, this is just another reason to get into casting bullets. Granted if they ban lead bullets for hunting I will be in a bit of trouble, but then I would keep the good stuff I have just for that, like my Speer Deep Curls.

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Vaya con Dios