Weird jam

[svandamme]

Originally Posted by Hoss in IL

On the rare occasion that I have a failure to return to battery with my re-loads, I can just bump the back of the slide with the side of my fist and it goes into battery.

I've had it fail to battery with the cheap mec gar mags a few times
When that happened there was a visible gap between the breech face and the barrel. And in those cases i could bump it shut

This is different, as the slide does not want to move, it's feels very stuck , needs quite some effort to release.
And there is no gap at the barrel / breech face

[BadOscar]

Originally Posted by svandamme

I've had it fail to battery with the cheap mec gar mags a few times
When that happened there was a visible gap between the breech face and the barrel. And in those cases i could bump it shut

This is different, as the slide does not want to move, it's feels very stuck , needs quite some effort to release.
And there is no gap at the barrel / breech face

This sounds like the extractor is too tight. Too tight can cause it not to go fully into battery and also make it very hard to eject a live round.

[Dave Waits]

something else to check is the length of your cases. No longer than .898". Also, you may want to take a 357 case, inside champher it til the edge is sharp and scrape out the headspace ring.Sometimes, especially if your cases are shorter than the ring, crud will build up in the headspace ring(45ACP and all Semi-auto cartridges that're straightwalled, headspace on the case-mouth).

Another thing, how many rounds on the Recoil spring?

[Hoss in IL]

Nice tip on using the .357 case as a carbon scraper, Dave. I'm going to make a couple of them.

[svandamme]

Originally Posted by BadOscar

This sounds like the extractor is too tight. Too tight can cause it not to go fully into battery and also make it very hard to eject a live round.

Would this be something i can set when i reassemble it?
Or is this a case of extractor needs to be modified?

Originally Posted by Dave Waits

something else to check is the length of your cases. No longer than .898".

I'll measure then, they had only been fired/reloaded once, had not measured them previously, was planning to do that on the second reload.
They are all from the same batch of factory Fiocchi.. I do't pickup other brass.

Originally Posted by Dave Waits

Also, you may want to take a 357 case, inside champher it til the edge is sharp and scrape out the headspace ring.Sometimes, especially if your cases are shorter than the ring, crud will build up in the headspace ring(45ACP and all Semi-auto cartridges that're straightwalled, headspace on the case-mouth).

I'll look into it, but i don't think there's much carbon in there, it's been cleaned with brake cleaner before, but i'll check.

Originally Posted by Dave Waits

Another thing, how many rounds on the Recoil spring?

About 700 Factory Fiocchi ball + around (600) softer reloads

How long should a spring last, and do you know what number Wolfs Spring goes in a PM7/45?


I did notice that the reloads with AA#7 seemed to make it dirtier then the Factory or VV N340 loads.. I was planning to discontinue the use of AA#7.. for this and other reasons (small flake, doesn't flow well in the power meter, the power also shakes out of the shells to easy on the 650, i generally don't like the AA7)


Thanks for all the tips Guys, i'm learning things here, much appreciated!

[Dave Waits]

Stijn, if you can get it I would recommend using Hodgdons' HP-38. It's the same powder as ww231 only less expensive. Burns very clean. Hodgdon owns the Winchester powder business now and all their powders are made by Hodgdon.

AA-7 is actually a little slow for the 45ACP, this and other powders at this point on the Burn-Chart may be what's causing your problem. 45ACP is a low intensity cartridge and powders for it should be on the fast side. There's not enough pressure-build to burn slower powders. If you want to stick with Alliant powder, I would recommend AA-5.

As for your spring, it should last about 3000 rounds or so, should be a 16lb.spring and the closed-end should go around the Guide-rod for proper operation.

What are using to lube the slide with? Either run it wet or use a good gun-grease like Plastilube or Tetra-Lube.

At this point, it seems that you have a fairly new gun and it's just breaking in. However, unburnt powder from the AA-7 and the lube you're using could be forming a sludge that's slowing down the slide.

One more thing it might be, what is your crimp diameter at the casemouth, should measure .470-.472.

Dave

[svandamme]

The last of the AA7 is out , i'm sticking with the N340 now, but i'll get some faster VV next time.. VihtaVuori lists N320 , N340 and N350, i went with the middle.

Spring was/is installed as you describe

No lube, just plenty of FP10, it sweats when it warms, so i'm pretty sure it's wet enough


I'll check the crimp over the weekend, I'm loading 5-600 rounds , brass is tumbling as we speak..

[Lane]

Originally Posted by Dave Waits

Stijn, if you can get it I would recommend using Hodgdons' HP-38. It's the same powder as ww231 only less expensive. Burns very clean. Hodgdon owns the Winchester powder business now and all their powders are made by Hodgdon.

AA-7 is actually a little slow for the 45ACP, this and other powders at this point on the Burn-Chart may be what's causing your problem. 45ACP is a low intensity cartridge and powders for it should be on the fast side. There's not enough pressure-build to burn slower powders. If you want to stick with Alliant powder, I would recommend AA-5.

As for your spring, it should last about 3000 rounds or so, should be a 16lb.spring and the closed-end should go around the Guide-rod for proper operation.

What are using to lube the slide with? Either run it wet or use a good gun-grease like Plastilube or Tetra-Lube.

At this point, it seems that you have a fairly new gun and it's just breaking in. However, unburnt powder from the AA-7 and the lube you're using could be forming a sludge that's slowing down the slide.

One more thing it might be, what is your crimp diameter at the casemouth, should measure .470-.472.

Dave

See what I mean?? This guy is a genius!!



Lane

[GoldenVolt]

svandamme,

Here's a good test when working up a new load or using a new bullet.

Remove barrel from slide, drop new round in chamber.

The round should be flush with the end of the barrel and should make a nice ping sound.

If it makes a thud, and the head (back of round) of the bullet isn't flush with the barrel, the bullet could be hitting the lands (rifling) of the barrel.

There are a couple things to look at.

1) case length. 2) Over all length. 3) undersized chamber 4) bad bullet profile.

Hope you get it worked out.

Greg

[BadOscar]

Originally Posted by svandamme

Would this be something i can set when i reassemble it?
Or is this a case of extractor needs to be modified?

See third paragraph here:
http://www.cotep.org/forum/showthread.php?t=566