Leading in 1911 Chamber?

[Cascade1911]

I was shooting my Springfield Mil-Spec yesterday, working up some new loads using W231 instead of my normal Bullseye. Toward the end of the session I had some failures of the slide to go fully into battery, I had to push them forward a little. I suspected my over all length might have been a touch long (I load my 230 gr LRN at 1.245" so it spaces off the bullet rather than the case mouth).
This morning I disassembled the firearm and found what looks to be leading in the chamber. A loaded round drags going in and this I suspect is the cause of the failure to go into battery. I suspect the reason is that I was shooting some pretty low pressure loads as I was working my way up, the case was not expanding in the chamber.
Has anyone else had this problem?

 

[g.willikers]

Low pressure loads with hard cast bullets will lead more than usual.
Light loads need a slightly softer bullet to reduce leading.
For a better explanation, check out the bullet casting and bullet makers web sites.

 

[Cascade1911]

I do understand increased leading in the barrel with light loads and hard lead (not enough force to deform the lead into the rifling) but what I'm looking at appears to be lead in the chamber. I know that a light charge will not expand the case to fill the chamber but I never thought the gasses bypassing the case would include enough lead to build up enough to prevent a cartridge from fully seating.

 

[g.willikers]

Maybe, since the reloads are head spacing on the bullet, the cases are just a little bit enough back in the chamber to allow the leading to occur there.
Not enough to cause the out of battery condition, until the lead builds up some.
Just guessing, though.
Try reloading with the cartridges head spacing on the case mouth and see if the problem goes away.

 

[Cascade1911]

Thanks for the help g.willikers. What I'm looking at is build up at least half to three quarters of the way back the chamber rather than build up in front of the case (like I'm used to when shooting 38's out of my .357 mag).

 

[g.willikers]

Now, that's weird, to have lead deposits way back there.
Powder residue makes sense, but lots of lead is different.
Maybe a better description of the reloads.
Like the powder weight, the diameter of the fired cases, diameter of the bullets, length of the cases before and after, and anything else that might help.
The over all length doesn't seem excessive, though.

 

[Cascade1911]

...and thats what I thought. I'll get into the loads in the Handloading forum but they weren't all THAT low, just prudent starting loads (low end of published data).

 

[Aguila Blanca]

This morning I disassembled the firearm and found what looks to be leading in the chamber. A loaded round drags going in and this I suspect is the cause of the failure to go into battery. I suspect the reason is that I was shooting some pretty low pressure loads as I was working my way up, the case was not expanding in the chamber.
Has anyone else had this problem?

Yes, but it isn't leading. It's powder residue. Take a look at your brass -- I'll bet the sides are black. If you're shooting very light loads, the cases don't fully expand and seal against the chamber wall, so there's some pressure (and powder residue) that gets pushed back along the chamber walls.

 

[GeauxTide]

Probably lead shavings that get smeared on ignition. Set your seating depth to headspace on the case mouth. Have shot a bunch of 200 SWC in my SFA without issue using dirty old Unique.

 

[Mike38]

Cascade1911, I recently had the exact same problem with 230 grain RNL. I seated the bullets .020 deeper and the problem went away.

 

[Cascade1911]

I'll give that a try Mike. Maybe spacing off the bullet is the problem.

Aguila Blanca, you are right in that I did see burn marks on the case sides and knew that I was probably running too light. What surprised me was to find lead rather than powder residue in the chamber (yep, definitely lead, scrapped it with a small screw driver and got little silver flakes) Maybe its the combination of the light charge and spacing the cartridge back. Once I get a good shooting charge I'll try moving the bullet back forward.