Con FUSION!

[briandg]

I had my clock out this afternoon. fired about 40 test rounds, reloads with aa2, 125 grain lead bullet, and i checked all of them before boxing them. After about 30 rounds, I had a jam. The round went into the chamber, and locked up with about 1/16 to go. I hauled it home, tapped the bullet out and pulled it with my intertial puller.

Before I pulled it, I went over ever bit of the surface with a 50x glass. I went over it all with a caliper, and it was all within spec. After pulling it, I found nothing at all odd about the bullet, other than a ring where it was forced back into the crimp when I tapped it out of the barrel.

After clearing the jam, I cleaned and thoroughly examined the barrel and gun. Nothing unusual that I could see.

WTH? Something caused this thing to hang up just short of the end of the chamber, and I can't find a darned thing. it was military brass, most iikely once fired.

Rounds were minimal, low pressure, nice softball rounds. the shells dropped at my elbow.

seriously, any ideas at all? it's going to be weeks before I can get back out and test fire again, using factory loads this time.

In fact, it was a pretty crappy day overall. My .357 loads failed me too. I had two occasions when the cylinder would not turn, upon opening, I found the bullets protruding a bit, enough that they were stopped by the forcing cone. So, did I accidentally let a few get light crimps? again, using my readers and a 50x glass, shoot, that crimp looked solid enough for minimal loads.

On top of that, I've not fired a revolver in a long time, and shooting SA on this thing showed a twitch/flinch.

 

[Jeffm004]

I had this with some .45 SNS Casting bullets because I left the bullet "lip"? protruding past the brass just that / much too far out. They hang up my 1911 and shoot fine in my Sig. I did not find it with a plunk test, I used a gauge and coated the whole shell with a sharpie. It still took several to find the problem, lead extending past the chamber and maybe a bit "/" wider. It was a pain to find and it was about 2 in 50.

Good luck.

Oh, as an added bonus, the gun will re-size them for you so it is really hard to catch, you have to check the ones you haven't cycled.

 

[briandg]

I didn't sit down and test the remaining rounds yet. I checked all of this as I loaded, as it was going to be the first box of ammo that I had loaded not only with this powder, but this bullet, and for this gun. I may have about 20 left to work with.

there just shouldn't be anything wrong. they were my hand cast, run through a lyman lubrisizer. The bullets were all lubed, and all showed scraping from sizing. the one I pulled looked totally normal.

If the glock has an incredibly tight chamber, maybe that's it. The thing was spotless when I went down. It was spotless when I cleaned it afterwards. No signs of lead, not even any dirt.

 

[PA-Joe]

Weak loads may not cycle the slide enough. You can also remove your barrel and drop each round in to see if it spins freely and is the correct length.

Sounds like light crimp on the others.

 

[TailGator]

Sometimes I can feel burs that I can't see, even with magnification. I run my fingernail around the rim when I have a cartridge that stops that far in on my chamber gage. Odd, though, that it happened after you checked them.

My first bet is the same as yours on the revolver rounds. If you didn't load them long, they backed out.

 

[Mobuck]

The 357 symptoms point to inadequate crimp.
It's also possible you failed to remove all the flare from the other rounds which failed to chamber as well. You didn't mention what caliber you had the stuck round with (9mm?).

 

[Mike / Tx]

Sometimes I have that happen with my Colt 1911. I think it is just a touch of lube that builds right in the front of the chamber where the lip of the case should headspace at, combined with just a touch of the lip on a particular case that might not have all of the flare crimped out. Can't prove it since I usually pull the round and go on with things. I use both the barrel and a case gauge and usually find the ones with the lip needing a touch of attention. However, with a little lube build up, and / or powder residue combined, that might be the added culprit.

On the revolver loads, I use a fair amount of crimp. Usually I start off light, then work into it to the point a single round will hold everything tight through three or more cylinders of the same load. I load six and shoot five, measuring the last one after each shot. When things move I add more crimp till they don't. It matter not whether it is a light wad cutter load or full bore magnum load, the process is the same. I also trim all of my target or magnum revolver cases to ensure a uniform crimp. I know most don't go that far in case prep for handgun loads, but shooting for group or hunting you want the best you can assemble just like with a rifle and I find it does make a difference.

 

[LE-28]

Did you check that your resizing die is touching the shell plate on your press. This will cause a bulge from an unsupported chamber to not be fully addressed when re-sizing the case.
Aside from the lead ring on the mouth you also have to watch for this. These bulged cases will seize up a semi-auto in short order.

If this happens again take the unfired case out of the chamber and go all over it with a sharpie marker or something, take the barrel out of the gun and push it in the chamber with your thumb, if the bullet is crooked or the case has a bulge, you will see a rub on the case.

if you find nothing get a pointed object and go around the mouth of the case with it to see if you find some loose lead. It's really hard to see and in most cases I have to use a machinist scribe or pick to see it. Chamfering the inside of the cases will help stop this problem.

On the .357mag, if you are using minimal loads and still have bullet jump, you don't have any neck tension.

Make sure all your re-sizing dies are touching the shell plates and with the .357 cases, make sure your not over flaring the case. You only need enough flare to just get the bullet to stick in it long enough to seat it. Any more than that is too much. You should have plenty of neck tension with the .357 mag cases to hold the bullets in place with no crimp at all on light loads.

I don't crimp mine at all unless I'm using a slower pressure building powder like 2400 or H110. I've never had a bullet slip.