Coated bullets and lead residue in the barrel question

[Dan_69GTX]

Latest update:  Finally got some "sport pistol" powder to try.

Loaded up a ladder using the .357 124 grain NLG bullet that gave me issues before.

Shot the ladder and decided on a powder charge. (shot about 80 rounds total)  Loaded up another 200.  Got through maybe 100 rounds and my rear sight broke.  .    So I guess that powder causes rear sights to break!   

Anyhow I took the gun and cleaned it and so far VERY preliminary results look good - no leading.  So, I'll get a new sight, and run another 300 bullets through and see what happens.

Maybe it was the powder? - I don't yet understand the WHY a powder would cause leading.  I have some theories which are hard to prove, but either way - maybe this will work and I'll save $$ by getting some decent ammo to have fun with using coated instead of jacketed or plated.

At least the sight didn't break on Saturday during a competition. 

[Wobbly]

Latest update:  Finally got some "Sport Pistol" powder to try. Got through maybe 100 rounds and my rear sight broke.  So I guess that powder causes rear sights to break!   

No, it wasn't the powder.

You were probably focusing on the rear sight and all that added extra pressure was just too much. This is why it's so important to focus on the front sight. It's much stronger and can take the extra load.

 

[Chuck in Indiana]

Ahh, I wondered why there was so much emphasis on looking at the front sight.. Mr. Wobbly comes through again. 

[newageroman]

Sport pistol is designed for use with coated lead bullets. The theory is that other powders will erode the base of the bullet over time and thus cause leading. I'm not subscribed to this theory, just noting it. I would think that the eroding effect with other powders could be reduced if you load then shoot them in short timeframe, or store you bullets nose up. I moved to sport pistol to try it out and like that its close to N320 but about half the price.

I recently bought a lot of 125RN blue bullets and they are undersized for my gun. I've not noticed leading issues, but group size suffered so my next purchase will be back to the PD124s(which I've used before with great results). I may try ordering a sample of the blue bullets that are specifically oversized for 38sp, I've heard they are better for most CZ barrels.

[Dan_69GTX]

You were probably focusing on the rear sight and all that added extra pressure was just too much. This is why it's so important to focus on the front sight. It's much stronger and can take the extra load.
 

And since I wear glasses that probably put additional load on it....sigh

Or, Painter broke the rear sight hoping I would shoot low and thereby shoot the chrono to distract others from always blaming him for it.

[ThompsonCustom]

Hmmm you should try caughting a bullet see what's going on since your bullets are not being undersized.

Just the other day I pushed some .357 115gr 9mm bullets out of my open gun (cz) over 1750fps which I dont recommend for anyone but the acme coated bullets handled it fine with no leading and the heat and pressure are double what most people would be using them for, I'm still thinking either the coating is failing or the barrel is not large enough for the barrel.

I didn't read ever post but if you haven't done the smash test that will tell you if your coatings good, covered a coat bullet with a rag and take a hammer and beat it close to flat 1/8 to 1/4in range. The coating should not chop or flake off at all.

[skin]

 I don't shoot lead much anymore, but I had the same problem with a 1911. I tried everything I could think of. When I slugged the barrel I noticed that the slug jerked and jumped about the last inch . I found that the barrel right there was a little bit bigger and then went back to the normal size. Just about a thousandth of a inch. Factory reaming defect. Jacketed bullets were accurate, lead was accurate also, but leaded the barrel. Switched the barrel and slugged new barrel, no leading and accurate.

[Dan_69GTX]

Another update:

Ran about 250 rounds of the Acme .357 124gr RN and still had a little leading at the end of the barrel.  So, problem not resolved yet BUT we DO know that the powder did help reduce the leading.

So, I now felt that the statements of the bullet not being big enough is the correct lead to chase.

Found that blue bullets sells the 125gr RN in .358 (for 38 special/357mag) so I ordered 250 of those.  Still using mixed brass, WSP, Sport Pistol I loaded up about 200 to try.  Wasn't testing for accuracy as much as for leading. 

Ran those through and NO leading at all. 

So, now I'll take the 50 or so bullets I have left and load up a ladder to see what the gun likes.  I know that the load I was running worked great (cycled), had a GREAT SD of 5.7 (lowest ever for me), and ran clean, but the group size was too big for me.

Now back to our regularly scheduled programming......

[viking499]

I picked up some of these awhile back, but have not had a chance to do anything with them.

http://missouribullet.com/results.php?category=20&secondary=26

I hope to come up with 2 loads, one super and one sub, to use in my range toys.

[Dan_69GTX]

I saw those when looking around.  But the only one I saw w/o a lube groove was the blue bullets version.  Also, I didn't want to got to 135 grain because I know I have to load short on my gun. 

The blues have to be loaded at 1.075, which is getting too short for my liking.  However they all fed just fine.

Maybe these blues will work fine....then I'll have the "blues" for the pistol and the "reds" for the Scorpion.  The Scorpion just loves the .357 ACME 124gr RN NLG.

[viking499]

I picked up some of these awhile back, but have not had a chance to do anything with them.

http://missouribullet.com/results.php?category=20&secondary=26

I hope to come up with 2 loads, one super and one sub, to use in my range toys.

Load info for the 135gr MBC coated here:
https://czfirearms.us/index.php?topic=96152.msg739645#msg739645


[Mods added all the missing info]

[Dan_69GTX]

Viking499  Thanks for the link.

[Earl Keese]

I'm still amazed you've had so much trouble out of this barrel(Scorpion right?). I wonder if CZ would look at it under warranty.
I've been loading Gallant 135rn in .357, I think I've finally found a bullet/load that works for matches in both pistol and carbine. They'll load longer, but I like them at 1.11, working well with Sport Pistol. I could load lighter for the carbine but I'm not good enough yet for it to matter, heck the Scorpion will never shoot flat anyway.   Having said all this, I've never had a leading issue in the Scorpion with any coated bullets, even the ones that leaded in a 75 barrel.

Sent from my XT1254 using Tapatalk

[Dan_69GTX]

Earl,
The Scorpion did lead a VERY little bit with the .356 ACME 124gr bullet.  With the .357 NO leading at all - so I got a good load there.

It is the SP-01 Target 2 pistol that likes to lead the end of the barrel.  I've had that for several years and have at least 25K rounds though it.  I was almost at the point of just forgetting coated bullets for it and just using the PD 124 JHP, but seems like I always need to tinker and see if there is something else a little better.  The leading issue now is more of a "I gotta figure this out" thing for me.

Just figured I'd update this thread as I go so in case it helps someone else in the future.  Always drives me nuts when someone asks for help/advice.  They receive it, but never report back what happened.

I DO really appreciate the advice, comments you have given!

[Dan_69GTX]

Next update:

Using Sport Pistol powder I loaded a ladder for the blue bullets .358 125gr RN.  I found a few loads that look very promising.  Initially I'd say as good as the PD 124gr JHP.  No leading so far.  So, I ordered a few more bullets to do further testing.

One interesting note - When I loaded the .358 PD FMJ bullets I didn't have good results - just the opposite with the coated .358.

All this testing was done in my CZ SP-01 Target 2, which leaded with the Acme .357 124gr bullet

UPDATE:::  It is .356 PD bullets - NOT .358