Was buying a few boxes of the pictured .357 for Range ammo and the sales person insisted JSP shoots dirtier than FMJ due to the exposed lead. I said without a compensator cleaning is the same with either, JSP won't lead the barrel as the jacketed portion will be in contact with the rifling

Korth’s cylinder gap is spec’ed at 0.003 inches, so I leave as little behind as possible.

Who is right? - Thanks!

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You are. Powder is also a contributor, and with some lead bullets, it may be the lube more than the lead.

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Formerly Model520Fan

He doesn't know what he is talking about! With either style all that contacts the bore is the jacket Different brands may use different propellants so powder fouling may be more with one than the other, but will come off with a patch and solvent either way.

Just because the guy works in a gun shop doesn't mean he is a shooter or knows anything about guns!

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Gunsmithing since 1961

That federal round has been around a long time and it's good for several uses.I would consider it a clean round.I can't tell the difference between total metal jacket vs full metal jacket by looking down the barrel after shooting.But i shoot mostly lead outdoors maybe the guy is talking about indoor shooting range which i've never done.

You have it right . The jacket keeps the lead from touching the barrel . So as far as leading in the barrel ... no difference
But ... there's always a But ..."Shooting Dirtier" could mean powder residue and a case full of slow burning powder (like 14 to 17 grs. 2400) will leave more residue than a few grains of a fast burning powder (like 2.7 grs. Bullseye) ...

Shooting dirty could mean barrel leading or it simply could mean powder residue / powder fouling .

You got to clarify what you mean by "shooting dirty " .

And the best way to tell which is what is to Choot Em' !
Don't take any salesman's word for anything ... I had one tell me a Weatherby Scope I was looking at could only be mounted
... on a Weatherby rifle ! I didn't buy the scope or a Weatherby rifle ... I knew better than that .

Gary

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Certified Cajun
NRA Member

Uninformed gun salesman. Copper jacketed bullets will leave some deposits in the bore. They just don't show up as readily as lead.

A little dirty or a lot dirty makes no difference in cleanup; it all requires the same effort.

if anything, the opposite would be true as the base of the FMJ, in direct contact with the hot gasses, is exposed lead.
A JSP is formed opposite of this, leaving jacket material to deal with the heat.

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it just needs more voltage

As a practical matter it does not matter. Cleaning is easy, but not necessary very often. Most of my handguns have bores that are a little dirty. Does not affect a thing. I do clean them with Hoppe’s from time to time, but I do not obsess over it like some people do.
The chambers in the cylinder are a different deal. I clean them much more frequently than bores. But I have no qualms about shooting a gun and putting it up a little dirty and not touching it again for 6 months or longer.

Sig striker fired pistols have spoiled me by being so easy to disassemble and clean. I really dread breaking down my 1911's and revolvers now for cleaning.

Even Lead SWC's will need very little in the way of cleaning. If they are shot at a reasonable velocity the cleaning procedure will be the same.

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S&WHF #946
S&WCA #3824

Best off to not listen to a gunshop commando. The whole purpose of bullet jackets is to prevent leading. I does not matter if it is FMJ, JSP, or JHP. I would further say that airborne lead is greater with many FMJ bullets as the jacket usually leaves the lead at the base of the bullet exposed to the hot combustion gasses.

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VCDL, GOA, NRA

Actually, I believe that, primers and lead bullets impacting a hard bullet trap contribute more to lead in the air at indoor ranges.

Well, they never did put out a test for gunshop workers, obviously.

I would not take that guys advice on anything. End...

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Freedom is never free!!
SWCA #3437

Uh, I think you mean "gunshop" not "gunship". Even then, the military obviously has some training mandate, the thugs in vans not so much.

But, post 8 has it right, most fmj has lead exposed at the base. TMJ/plated not.

Propellant powders make a difference. Also, not all bullet jacket materials are the same, ranging from pure copper to brass (copper-zinc alloys), bronze (copper-tin alloys), copper-nickel alloys, mild steel (with or without plating or shellac coatings), even aluminum and zinc has been used in commercial ammunition. Every combination will vary in how it reacts to flame temperature of the powder burn and bore friction.

A related argument can be made that overly zealous or harsh cleaning methods are more harmful to the firearm than any amount of shooting, regardless of the ammunition type.

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Life of the party until 8:00PM

Was going to buy some ball valves "NOBODY USES BALL VALVES ANY MORE! I couldn't be a salesman of that type. I don't care if Ed McMahon could teach you how to sell anything.

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"He was kinda funny lookin'"

Another way to look at it would be that any fouling differences would be minimal at best. As for cleanup, any jacketed bullet whether it's FMJ or some other configuration will leave at least a small amount of copper fouling. This needn't even be removed unless accuracy is adversely affected. It probably won't be unless you've done a great deal of shooting or the compulsive bug bites which won't allow a gun to be put away unless the smallest amount of fouling is reduced to bare metal. "Bare metal" cleaning is not recommended because it may affect accuracy in a negative way until the bore is slightly fouled.

I don't know anything about Korth guns, the .003" gap, etc., but is there some truly valid argument for treating such guns any differently than other good quality firearms?

I may be overlooking something of importance here, but I don't think so. However, I see I've fallen into the trap of commenting on a matter of little worth, just as others have.