Recently got into reloading, and am loading a 115gr LRN from missouri bullet with 4.0gr of Universal, COL of 1.100. I have noticed that after 100-125 rounds, I am getting a lot of buildup (I assume leading) just forward of the chamber. Is this normal?
9mm leading too much?
- Thread starter no_agenda
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SCPigpen
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I'm not familliar with Universal but the charge may be too hot for cast bullets.
LiveLife
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no_agenda, leading is usually deposited in streaks/strips down the barrel along the grooves of the rifling. Bullet lube and fouling from powder ignition is typically black residue that comes clean with Hoppes #9 solvent.
I usually run my copper bore brush with dripping amounts of Hoppes #9 solvent several times through the barrel and let the solvent soak for 10-15 minutes. After the soak, almost all the fouling will come clean revealing any leading in the barrel.
Below is the load data for Universal and 115 gr bullet:
I usually run my copper bore brush with dripping amounts of Hoppes #9 solvent several times through the barrel and let the solvent soak for 10-15 minutes. After the soak, almost all the fouling will come clean revealing any leading in the barrel.
Below is the load data for Universal and 115 gr bullet:
Too light of charge will not obturate the bullet base (expansion of the bullet base from the expanding gas "bump" to seal against the rifling) and allow the hot gas to escape around the bullet causing "gas cutting" that will put a lot of fouling at the chamber end of the barrel.
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Hmm. Leading next to chamber area indeed indicates that the pressure is too high for the bullet hardness. See here.
On the other side, QuickLoad with the above parameters shows that the max pressure is below 20K PSI. According to the above-referenced article. the bullet hardness (BHN) should be no less than 10 to provide enough torque to spin up the bullet and have no leading at that area. Missouri bullet states that their bullets are harder than BHN 10.
I would suggest to slug your bore. May be it is too large for the bullet, and the buildup is caused by gas cutting.
On the other side, QuickLoad with the above parameters shows that the max pressure is below 20K PSI. According to the above-referenced article. the bullet hardness (BHN) should be no less than 10 to provide enough torque to spin up the bullet and have no leading at that area. Missouri bullet states that their bullets are harder than BHN 10.
I would suggest to slug your bore. May be it is too large for the bullet, and the buildup is caused by gas cutting.
LiveLife
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no_agenda, I was referring to an older load data I had on my computer. I just checked the Hodgdon website and it indeed shows lower load data for Universal (corrected load data for my post).
Well, do verify whether the fouling is lube/powder residue or actually leading.
Well, do verify whether the fouling is lube/powder residue or actually leading.
Four Knives
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Also curious because I'm having some leading in a G22 with Lone Wolf Conversion Barrel.
Missouri Bullet 115gr LRN over 4.3gr W231 with 1.090 OAL.
I'm loading a bit short because otherwise the projo will engage the rifling in my Sig P6 upon chambering and keep it from going into battery, so I'm trying to make a paper punching load that will work in the P6 and the G22 with conversion barrel.
The leading evidences itself with smears in the grooves of the rifling early on for about a centimeter or centimeter and a half.
Also curious because I'm having some leading in a G22 with Lone Wolf Conversion Barrel.
Missouri Bullet 115gr LRN over 4.3gr W231 with 1.090 OAL.
I'm loading a bit short because otherwise the projo will engage the rifling in my Sig P6 upon chambering and keep it from going into battery, so I'm trying to make a paper punching load that will work in the P6 and the G22 with conversion barrel.
The leading evidences itself with smears in the grooves of the rifling early on for about a centimeter or centimeter and a half.
LiveLife
Member
no_agenda, if the fouling is near the chamber end and especially hard to clean, you are probably getting gas cutting. Too much charge typically causes leading at the end of the barrel.
Gas cutting occurs because powder charge is too light to obturate the bullet base or bullet hardness is too hard and diameter is too small for the barrel so hot gas is escaping around the bullet. Mind asking which pistol you are shooting out of?
You could cover all bases and test load some at lower/higher charges (say 3.8 and 4.2 gr) and see if the fouling gets better or worse. If the fouling decreases with the higher charge, then lack of obturation is the cause for the fouling.
Four Knives, I have not shot the 115 gr MBC bullet. I do like the 125 gr Small Ball for the LW conversion barrel for G22/G27. I have gotten minimal leading with 4.3 gr of W231/HP38, but I was range testing different OALs from 1.08" to 1.12" so I am not sure which OAL may have caused the leading.
I am planning to do more test loads at 3.8gr /4.0gr using 1.10" OAL. If leading problem gets worse, then I will go back to 4.3gr at 1.10" OAL and see what happens.
Gas cutting occurs because powder charge is too light to obturate the bullet base or bullet hardness is too hard and diameter is too small for the barrel so hot gas is escaping around the bullet. Mind asking which pistol you are shooting out of?
You could cover all bases and test load some at lower/higher charges (say 3.8 and 4.2 gr) and see if the fouling gets better or worse. If the fouling decreases with the higher charge, then lack of obturation is the cause for the fouling.
Four Knives, I have not shot the 115 gr MBC bullet. I do like the 125 gr Small Ball for the LW conversion barrel for G22/G27. I have gotten minimal leading with 4.3 gr of W231/HP38, but I was range testing different OALs from 1.08" to 1.12" so I am not sure which OAL may have caused the leading.
I am planning to do more test loads at 3.8gr /4.0gr using 1.10" OAL. If leading problem gets worse, then I will go back to 4.3gr at 1.10" OAL and see what happens.
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If your bullet is undersized, it will lead. You need to understand that most 9mm pistols do not have .355" groove barrels. Many have .357/.358" barrels just like .38 cal. revolvers. I used to own three Beretta 92's. I was using .359" lead bullets in them to prevent leading. The reason was the barrel miked .358" and the throat miked .360". The bullet needs to be a snug fit, yet small enough to chamber reliably. But it cannot be .002" or .003" undersize because propellant gasses will overtake it before it even enters the bore. If that happens, the bullet will be gas-cut and molecular lead in a vaporized state will travel in front of the bullet and stick to the barrel. That's how you get leading with low pressure, slow moving lead projectiles.
Its is a Glock 19 with Lone Wolf barrel. Also, allegedly missouri bullet co. has "harder" cast lead than most, and I have heard (just now on a podcast) that gas cutting will occur if a load is too hot with softer lead AND if the load is too light with a harder lead bullet. So....I need to increase my load....
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18 is pretty hard. What powder weight did you try? You may need to bump it up a couple tenths at a time until the leading quits or you get to max. If it still leads, your barrel may be a bit on the large size. It may require a bigger bullet than .356. Trying a .358 bullet is worth a try, assuming it will chamber. Won't hurt to load one up and see.
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