Breech of the Piece

The day dawned overcast, damp, and slightly chilly: standard fare for Washington state. I was not deterred by the weather, though, for today I would be firing my 1911 for the first time. Bolting my breakfast, I hurried to the range with the newly-completed gun. With the targets in place, I chose a magazine, loaded a single round, and with nervous hands tripped the slide release.

Clunk.

Anticlimax.

The round didn't even feed off the magazine, no matter what I tried. This was definitely puzzling, as snap cap after snap cap had fed through this very same pistol. Disappointed, I returned home to investigate further. The complete and utter failure to feed under all circumstances made it highly unlikely that this was a standard jam; more likely was the possibility that the cartridge was being prevented from sliding up the breech face. The extractor was the likely culprit here, but it didn't look like the rim was even making it high enough to engage the extractor:

So what extractly is the problem?

Finally, I measured the breech face width at the bottom and found it was 0.475" across, which wouldn't be a problem if .45 ACP didn't have a rim width of 0.480". I'd heard of this problem occurring in slides found on Sistema Colts, but had never expected to run into it myself. The snap caps had worked fine because they were built undersized to start, and the edges of the rims had been chewed up by repeated chambering. I'd found bits of aluminum inside the gun, but it had never occurred to me to wonder which part of the snap cap had produced those chips.

Widthout a doubt the source of the problem.

The solution is to open up the bottom of the breech face to about 0.484" wide by taking material evenly off both sides, beveling the extractor's tensioning wall to make the bottom flush with the new width if necessary. More room can be provided by taking an addition 0.004" off the side opposite the extractor, bringing it to 0.488". Some builders will open it up all the way to 0.490", but removing the minimal amount of metal is always a good starting point. A slight bevel on the bottom edges of the breech face will help funnel the rounds into place and complete the job.

Rank and file.

The tool for this job is a narrow #2 Swiss cut pillar file. Swiss cut files are cut with fineness proportional to their number, so #2 is fairly fine. Someone who knew what he was doing and had several of these things might opt to start with a #0 to open up the face to within a thousandth of an inch of where he's trying to go, then sneak up on the final measurement with a #1 or #2. As a ham-fisted amateur, I opted to take it nice and slow.

Defiling the slide.

After opening up the extractor side of the breech, I proceeded to the opposite side. In both cases, the filing was tricky work due to the limited space and constricted angles; maybe a #0 file would have helped speed things up.

Opening up the breech under the extractor left a little bit of the extractor exposed, so I very carefully used a small needle file to add a bevel to it, then cleaned it up with some 600-grit sandpaper.

The bevel's in the details.

With the extractor beveled, it fitted nicely with the reshaped breech face:

We've breeched a stopping point.

I'd thought filing the breech face open had been a chore, but it was nothing compared to putting a bevel on the bottom corners. I finally managed to put a small bevel in place, but it was very difficult to do while avoiding inadvertently filing other parts of the slide.

One final thing to note is that after extensive filing in one place with a single file, you're left with some fairly deep filing ridges. Standard metalworking procedure, I'm told, is to file with successively finer and finer files until the ridges are reduced; I had to use sandpaper wrapped around the file. It worked, but I could see how the proper tools would have made the job a lot easier. What a strange concept.

After cleaning up the filings and reoiling the gun, I was ready to go again. Now I would definitely be able to test-fire the gun for sure. Not like last time.

Or would I?