Excessive leading?

[cdet69]

Can an oversized bullet cause excessive leading?

[Mr Humble]

Usually leading is caused by blowby from too small bullets. The classic is the Colt SAAs with small throats and big barrels. With black, the bullets forced thru the small cylinder mouth might "bump up" but with smokeless leading was almost a sure thing. Many articles have been written about fixing this problem.

Too soft an alloy, pushed to hard with a lube that fails can also cause leading, but undersize is worse than oversize.

Have you slugged the bore ?

[stubshaft]

Yes, boolit fit is the most important thing but not the only thing.

[cdet69]

No I have not slugged my bore. I will try it today and see what I get. It is an 1903 Springfield in 0-06 and I was using bullets sized to .311. Not sure if the lead was there before I started though.

[bowenrd]

I use .311 in my '03 Springfield.

Are you using gas checks? I never had any luck shooting rifle without gas checks.

Is the bore absolutly 100% clean before shooting cast? If the bore is fouled from years of neglect it will lead terrible. Use a good copper solvent. It may take a couple of days to clean. Keep running solvent patches until there is no more blue/green showing.

My avatar on the left was shot with cast at 100 yards with a Rem M700 30-06.

[captaint]

What kind of lube are you using ?? Mike

[375RUGER]

Not sure if the lead was there before I started though.

Scrub the bore clean. Get it free of all copper, lead, and other fouling. Make sure all copper is removed.
Do this before you slug.
With a super clean barrel, now you can go to the range and you will know if it's something you are doing.

[MBTcustom]

Use a gas-check,
leave the size alone,
pull a boolit and make sure its still .311 after you load it,
Use a good lube like FWFL or Javelina
For the most part, I would answer your original question "no" but that's not completely true. I have had trouble getting a GC boolit past 2600FPS without leading and the '06 can easily push faster than that.
If your boolits are going slower than 2600, have a good gas-check, good lube, are hard enough for fast shooting (3% antimony, 2.5% tin), and are actually the same size that they were when you loaded them in the cases, then I say "no they cannot cause excessive leading".

[Cadillo]

I would clean that barrel down to the bare steel before I even started to experiment with lead boolits. I only cast for handguns, but have learned that what folks here say about lead sticking to jacket fouling is true.


No I have not slugged my bore. I will try it today and see what I get. It is an 1903 Springfield in 0-06 and I was using bullets sized to .311. Not sure if the lead was there before I started though.

[Mr Humble]

When are we gonna get over the jacket fouling myth ? If the bore is clean (not fouled with chunks of jkt material), a cast bullet could care less if there is a jacketed bullet "wash" in the barrel. The reverse is also true. All this assumes you have an excellent barrel to begin with.
For example: in my Browning 1885 45-70, I switch back and forth between lead and jacketed, black and smokeless and it could care less. If you have a barrel that fouls with jacketed bullets or leads with lead, you have a rough bore. My Browning looks like a mirror inside, many other brands or old military rifles usually do not. There was a reason Harry Pope hand lapped his barrels and why all of today's best barrels for lead bullets are hand lapped.

As far as 1903 Springfields go they range from bench rest quality like the NRA Sporters to rough as a cob like a lot of WW II 03A3s. Until you slug it you don't know if it varies end to end from .306 to .313 or if even what diameter it is. Until you put a borescope in it you really can't know what the bore's condition is.

Good shooting !

[cdet69]

Bore slugs at .310 with a loose spot about 3" from the muzzle. I do not know if it is fouled with copper. I am using a 180 grain bullet coated with Lee Alox lube. The bullet has a gas check.

[MT Gianni]

In general leading at the muzzle end is probably lube failure and leading at the chamber end is generally a lackof proper fit.

[Mr Humble]

That loose spot is a problem. Back in the day most guns designed for cast bullets were choke bored (got tighter as you went to the muzzle.) A .313 bullet like a 180 Loverin that carries a lot of lube and is long might bridge that loose spot. Don't cast it too hard and don't try to push it too fast.
You didn't mention the barrel date so hard to guess how smooth it was when made, but a fire lapping probably would do no harm.

[cdet69]

The barrel date is 1918. So it is not to far off from being a hundred years old. Still groupes 3" at 100 yards with my shooting abilities.