9mm Cast lead. Glock.

[coalman]

There should be NO sizing down of lead in the reloading process, period.

"Should" being the operative word IMO. I used mixed brass and the cheapest LRN I could find (because cost savings is the whole point even to hassle with LRN in 9mm for me). Seat lead bullets in mixed brass, and seat FMJ (not plated) bullets in mixed brass, then pull both and check size. Unless I belled cases more than I prefer, I've found seating the 9mm LRN in the case will size away that .001" difference much of the time, assuming the bullet was .356" to start with since I don't check every bullet. I never had issues with neck tension regardless though.

p.s. keep in mind my reply was specifically regarding that the extra LRN .001" provided "better" neck tension.

 

[Steve A]

Here is a good lead bullet for 9mm or .38 Super:

It is a 130 Grain LSWC - IPSC section - then look in the .38/.357 portion.

http://www.bulletworks.com/

 

[ljnowell]

"Should" being the operative word IMO. I used mixed brass and the cheapest LRN I could find (because cost savings is the whole point even to hassle with LRN in 9mm for me). Seat lead bullets in mixed brass, and seat FMJ (not plated) bullets in mixed brass, then pull both and check size. Unless I belled cases more than I prefer, I've found seating the 9mm LRN in the case will size away that .001" difference much of the time, assuming the bullet was .356" to start with since I don't check every bullet. I never had issues with neck tension regardless though.

I dont sort my brass so I use mixed brass in 45acp, 9mm, and 38/357. I do sort for 45 colt. Never had a problem with it. Brass isnt hard enough to cause that. Brass will expand before bullet shrinks. Brass has a different spring back though thats the reason when people swage down a bullet with a lee factory crimp die you lose neck tension. The brass will spring back a little and the bullet wont. Thats a super hard carbide ring and when it resizes lead it makes a solid contact you have to push through. Brass isnt sizing down the lead unless you are shaving a bunch of it off.

There has to be an issue somewhere else.

Dont take it as though I am trying to be argumentative or critical, I just want to make sure that there isnt another problem you are battling. I have done it before myself, trust me.

 

[LiveLife]

cast lead for a 9mm factory Glock G17.

IMHO, shooting lead loads in factory Glock barrels can be done with some considerations. Glock barrels differ from typical barrels (that have square cut land/groove rifling) by having rounded rifling with longer leade/freebore and very smooth start of rifling - http://www.thehighroad.org/showthread.php?p=8464678#post8464678

Below is an example of a square cut land/groove rifled barrel with rifling that tends to dig/cut into the lead bullet surface

In comparison, Glock barrels have very smooth rounded rifling with gradual/smooth start of rifling that may not allow the bullet surface to grip the rifling as well

These aspects of Glock barrels may allow the lead bullet to slide deeper into the rifling before the chamber pressure starts to build during which time more high pressure gas leaks around the bullet, more liquefied lube is blown off the bullet surface and gas cutting/bullet base erosion increases.

IME, these will result in more flaky/crusty fouling deposit along the rifling. Below is a Glock barrel after 100 rounds of lead loads and you can see the flaky/crusty fouling deposit especially along the rifling.

In comparison, below is a Lone Wolf barrel after several hundred rounds of the same lead load. As you can see, there is no flaky/crusty fouling deposit, just residual lube smearing.

IME, the flaky/crusty fouling deposit on Glock barrels don't initially affect accuracy until around 100-200 round count. More importantly, if the fouling deposit is allowed to continue, you may essentially end up with a smooth bore barrel with a reduced groove diameter which will probably increase the chamber pressures.

For these reasons, I usually recommend inspection of the Glock barrels after 200-300 lead rounds and clean as necessary to ensure accuracy is maintained and fouling build up is removed - http://www.thehighroad.org/showthread.php?p=8465230#post8465230

 

[JohnKSa]

I usually recommend inspection of the Glock barrels after 200-300 lead rounds...

I think it would be wise to be even more conservative than that given the results of Mark Passamaneck's investigation/measurements.

As I mentioned earlier, he noted that he tried the same lead bullet load in two apparently identical Glocks and found that one, after having fired only 75 rounds, exhibited twice the effects of pressure increase as the other pistol did after having fired 300 rounds.

So while your experience, with your Glocks may indicate that inspecting after 300 rounds is sufficient to insure safety, Passamaneck's observations note that another, apparently identical gun, might actually show double the effects after only 75 rounds that your Glock shows after 300 shots fired.

Assuming the process continues in a linear fashion, after 300 rounds, such a gun could be showing 8 times the effect of pressure increase as your gun.

 

[blarby]

So, BDS- you think a shorter or longer bullet, or a profile difference, would help in a factory BBL ?

For all of the testing thats been done, you think I could find a reference to the exact bullets being used....... but I can't.

We have this ability to you know, carefully craft the bullet design to suit the purpose at hand

 

[LiveLife]

blarby, I did preface my post with this

shooting lead loads in factory Glock barrels can be done with some considerations

As JohnKSa posted, there are variables to consider. I do not know what Mark Passamaneck's lead loads were but my loads were Missouri 18 BHN 125 gr RN using high-to-max range W231/HP-38 lead load data referencing 1999 Winchester load data (124 gr LRN W231 Start 3.3 gr (910 fps) 23,800 PSI - Max 4.0 gr (1035 fps) 32,900 PSI) and 4.0 gr Promo load using Red Dot load data (as indicated by Alliant) referencing 2004 Alliant load data.

Previously I have used 22-24 BHN stepped 124/125 gr RN bullets (nose profiles like the Dardas/ZCast RN above) with high-to-max load data W231/HP-38 and got mixed results that included increased leading/fouling build up and decreased accuracy (BTW, ZCast advertises 14-16 BHN and Dardas offers both RN profiles in 16 BHN).

... shorter or longer bullet, or a profile difference, would help in a factory BBL?

IMO, bullet profile that allows for longer bearing surface (nose profile like Missouri RN/CN or SWC) and subsequently gets seated deeper in the case neck than stepped RN bullet profile may build more consistent chamber pressures faster to address Glock barrels' rifling. Also, a softer lead alloy (say 16-18 BHN) will deform faster to obturate the barrel to reduce high pressure gas leakage/gas cutting/bullet base erosion etc.

What I have noticed while shooting Missouri 18 BHN 125 gr RN lead loads in factory Glock barrels in comparison to 22-24 BHN 124/125 gr RN lead loads is that the softer 18 BHN bullet loads produced less leading and fouling build up that maintained accuracy longer. Perhaps this was due to better obturation from softer lead alloy that sealed the high pressure gas sooner to reduce gas cutting/leading/blowing liquefied lube etc.