External extractor: How should it fit up?

[Ray P]

I'm on my third or fourth iteration trying to get a Star Firestar M43 to extract consistently with whitebox target (read: cheap) ammo.

1st: The gun has made two 6-month long trips to the local gun store's contracted gunsmith, with the original extractor. The professional smith really deepened & exaggerated the hook, but the pistol still failed to extract about 75% of the time.

2nd: After some forum discussion a year or so ago, I swapped out the barrel thinking I might have a chamber problem. No effect. Original barrel restored.

3rd: I purchased a new extractor, pin & spring from Spain. Not knowing how to fit it up, I did a straight drop-in. It now extracts 80% of the time; and if I use top of the line 124 gr JHPs, there is no extracting problem.

I'm wondering what else to try. After searching the gun forums, I found a few threads on the subject, but nothing of direct benefit. Another thread on this site did talk about checking the fit-up of the case to the breach face, but I'm not sure of the results I found.

Per the sketch below, I measured the gap between a fired case and the breach face when the cartridge rim was fully engaged by the extractor. My Star with old extractor & pin had a 0.032 in gap. The Star with new extractor & pin had a 0.024 in gap. At first, I thought this might be my problem; excessive gap. But I just did the same check on my S&W 639. Here I show a 0.026 in gap.

Not wanting to shoot gold dots for all occasions, are there any thoughts on what to try next; or a recommendation on a smith that understands external extractors?
View attachment 275588

edited to correct "0.24" to "0.024"

 

[model 649]

Here's a few thoughts. Check spent cases for marks on the case web (just above the rim). I have experienced a condition where the extractor hook was sometimes contacting the case web on firing and the hook would be "bounced out" and fail to extract. In your sketch, look at the area at the top or chamber-facing end of the hook and the case web to get an idea. Put a case into the slide and push it back against the breechface. The top or forward face of the hook should NOT contact the web of the case hard as you push the case against it. It can be almost or VERY BARELY contacting with the head of the case when its firmly against the breechface(preferrably not touching). Else-wise, the extractor should be able to hold a complete cartridge when mildly wiggling or shaking the slide(try this with the slide off the frame). They don't have to have monster-tension here. The case rim is held by a pinching action between the extractor hook's inward surface and the left inner wall at the breechface. Be sure there aren't any deep gouges, etc. at that area where the case rim contacts the slide(opposite the hook). I haven't seen your exact extractor set-up, but some hooks are fitted for depth-of-reach into the slide by removing metal from the hook where it contacts the slide on it's inner (hook-side) surface. It's best to match it up with the part originally fit to the slide when replacing. The extractor springs also weaken over time (usually several years at least).
Hope this helps you.
Josh

 

[Ray P]

Thanks, Josh!

I'm gonna print this out, and read it about 5 or 6 times with the slide, barrel and a case in hand.

some hooks are fitted for depth-of-reach into the slide by removing metal from the hook where it contacts the slide on it's inner (hook-side) surface. It's best to match it up with the part originally fit to the slide when replacing.

I strongly suspect you are correct on needing adjustment for depth of reach, but I am reluctant to use the old one as a guide as it worked worse than the new one.

Thanks again,

Ray

 

[mete]

How's the chamber ? Polished or rough ? A rough chamber can cause problems.Compare fired and new cases between 'top of the line ' and others.

 

[Ray P]

Finally got a chance to fire 50 rounds in the gun today.

The mix was 20 rounds of speer 124 gr JHP, and 30 rds of Rem 115 gr JHP.
I had 5 magazines: 1 new factory mag, 2 older factory mags that came with the gun when I bought it, and two aftermarket magazines.

1. As I expected, no failures to extract/eject using the higher-end ammo. Surprisingly, I did have 2 FTF; both happened (once each) in the two old factory mags; both times on the 2nd round in the stack. This could be a spring problem.

2. All the brass shows a consistent pattern: Looks like the hook is riding on the case above or forward of the rim.

View attachment 276334

(edited to correct spelling)

 

[NeoCan]

My M43

I've had an M43 FireStar for years...
I was using it as a carry gun until a few years ago when it started to have extraction problems.
I took it to one gunsmith, but the problem persisted.
Since then, the gun has stayed in the closet...
However...I'd still like to use it.
My problem is that it fails to extract about 10 - 15% of the time, no matter what kind of ammo that I use. (Not good for a carry gun.)
I'm willing to pay IF a gunsmith can fix it...
I'm not skilled to do it myself...
Any recommendations on a gunsmith?

[email protected]

 

[Ray P]

Welcome to the site, NeoCan!

I'm asking for extractor info here because I haven't found the smith yet that really knows these guns.