Good day

I have a model 27 from 1980 and I get exsessive leading when I shoot LSW. After about 20 shots I can scrape lead out the barrel, I shoot 158 grain LSW with a hardness of 22 brinel.

I did slug the throut of the cylinder and they are .359 and so are my bullets

Does someone know if this is the cause of the problem and if the throut is to large.

Brgds
Herman

Drop it down to 0.357" or 0.358".

How are bullets lubed or coated? How hot are they loaded? Like mentioned try some smaller. Is guns timing good,? Just that many rounds causing bad lead is all wrong

If your throats are truly .359", .359" bullets should work okay, but a .358" bullet might work better. Worth trying. You don't mention whether you're using .38 Special, .357 Magnum, load, or velocity. Makes a big difference. Even with maximum .357 Magnum loads, the bullet alloy could be too hard and that in itself can cause leading.

Yep that is a hard alloy.

38 special loads with titegroup, n320, and Ba9 all give leading.
Loads are between min and max.

Timing seems ok no problem that I can see

Alloy is much too hard for .38 Special loads. About 10-12 BHN would work far better, particularly if bullet fit (diameter) is right. You should have no leading with this combination even using maximum .38 Special loads. Most commercial bullets have hard lubes. They will work fairly well, but a soft lube would probably be even better.

22 BNH would be good for rifle velocities - 38 special not so much. What kind of load are you doing?

If the throats and barrel are .359 then .359 should be the best diameter but sometime you just have to experiment to find out what works best.

22 Brinell is way too hard and probably the reason for leading.
Brinell vs. velocity is discussed here;

Brinell level vs. velocity guidelines

I've found that very hard alloy causes more leading than it prevents. Try softer alloys and Lee Liquid Alox lube. The liquid alox has almost totally solved my leading problems.

I use Dardas RNL (.358") bullets with a hardness of 15 - 16 and don't really get much leading. I like the RNL configuration because they seem to deposit a lot less lead than SWCL does due to its sharp shoulder. The RNL shape is not sharp and eases its way into the forcing cone easier and with less leading.

When you are removing the lead, the Lewis Lead Remover (sold by Brownell's) is the best and most efficient way to get it out.

I've experimented with different alloys in the .38 Special and many other handgun and rifle cartridges. I think others who have done extensive work in this area will support my findings... using light, moderate, or maximum standard pressure loads, a soft 1 in 16 or a 1 in 25 (tin / lead ratio) bullet almost always shoots more accurately and with less leading than a Lyman #2 mix which is about 15 BHN. Plain wheelweight alloy, about 12 BHN, will also do better than Lyman #2. In fact, with moderate .357 Magnum loads, the softer alloys still often beats the harder Lyman #2. I don't shoot magnum handgun loads of any kind any more, but Lyman #2 will come into its own and show an advantage with warm .357 Magnum loads (or magnum loads for other cartridges).

The bullets are about the only ones I can by and acc the manufacture they are 22. I use the same brand in my .45 colt Blackhawk 255 lsw light loads and in 300 grain ruger loads and I have no leading at all.

The bullets can be pushed with a little force thru the the cylinder.
Will get some other bullets from a friend that makes his own bullets and these ar sized at 358 with a gas check.

The loads that I use are
3.5 grain titegroup, heavy leading
5.0 grain Ba9, leading
3.5 grain N320, leading

Increasing a powder charge will often serve to decrease or eliminate leading, but Titegroup and N320 are roughly Bullseye powder equivalents and your 3.5 grain charge of either powder is probably around maximum, so I would not increase either charge. I am unfamiliar with Ba9.

Pushing bullets through a cylinder with slight force is a good measure of fit, but the alloy must be "right" or close to it for the intended pressure of the load. The .358" gas checked bullets may be too small in diameter but are certainly worth trying. Gas checks won't eliminate leading in most cases, but they will often reduce it. However, one shouldn't "need" a gas checked bullet even for recommended maximum .38 Special loads.

I don't know about the .45 Colt loads you describe. I suppose very light loads may be exempt from leading if bullet fit is fine, but I have little or no experience with very hard bullets fired at low to minimal pressure.

There are exceptions to everything including cast bullet usage. Accepted "conventional wisdom" and rules don't work 100% of the the time. Experimentation is usually worth the effort. Good luck-

I gave some of the bullets to a friend that has a Saeco hardness tester and acc to him they are between 10 and 12 BHN wich is far below the value I got from the maker. Did send them a mail about this but they did not replied yet.

But this means they are to soft for magnum loads I guest but should still be oke for .38 special loads or not.

Ba9 has almost the same burn rate as N320 when I look at the vithavuori burn chart.

I have to start over again with my test loads I think.

Occasionally I find pushing a bore slug down the barrel that it abruptly stops at the junction point where the barrel threads onto the frame . When indexing the front sight , if they over tighten the barrel to get the sight alignment correct it causes a " tight spot " there . It down sizes the cast bullets , causing sometimes severe leading .
Leading is a " subjective " issue . I don't call pulling a few flakes out of the barrel when cleaning " leading " . If I get pieces an inch long , or more then I realize there are some issues that need attention .

The lead deposits are just after de forcing cone, and they are not that long. I never had a problem with leading before, i am use to shoot FMJ 9mm, .45 acp. With my 686 I shot lead wadcutter .38. Targetloadsand had no probblems with leading with those. With the model 27 I want to shoot .38 plus loads and 357 magnum loads and than the leading apeared. Does some one can give me a example of server leading and leading the is acceptable (pictures)

Brgds
Herman

BINGO.........358 with a gas check , that should cure it.

Another trick you might want to try is loading 9 mm bullets, use a taper crimp (I use my 9 mm taper crimp die to do this)
I found a cast 120 or 124 grain truncated cone 9 mm , sized .357 , shot extremely well in 38 special-357 magnum.
Jacketed .355 might also work, load a few and give them a try .

Gary