FAS 6007: FTF due to weak hammer spring?

[lognom]

Hi,
I have a FAS 6007 that I've been happy with except for a ftf issue. Every magazine one or two bullets won't fire. I've tried different ammo brands, the firing pin is intact, and I've thoroughly cleaned the bolt and breech. I assume the problem is the hammer spring but Chiappa is on back order. Is there any way to purchase a generic hammer spring or does it have to be a factory spring? I read on this forum that Domino FAS pistols were prone to weak hammer springs so maybe the Chiappa version has somehow inherited this?

Thanks,
Lloyd

[David M]

https://www.gunsprings.com/index.php
Measure the coil diameter and wire diameter and match the spring.
You can buy a long length and cut/grind to size.
Welcome to the world of Italian springs....

[lognom]

David M,
Thank you.

[fc60]

Greetings,

For a TEMPORARY fix, try this...

Remove spring and measure the free length.

Now, stretch the spring about 40% longer.

Important, place the spring in your oven and temper at 450F for 30 minutes.

Cheers,

Dave

[spektr]

Respectfully, another possibiity is a dirty chamber. 6007s have tight chambers to begin with and a bit of build-up results in the round not fully seating. The firing pin will strike the round and instead of going off, it is pushed further into the chamber, the rim will have the appearance of a light strike and it will drive you nuts. Cleaning the bolt face and breech is inadequate to fix it....... you need to scrub the chamber. I use a nylon brush wet and follow it up with dry patches.

[Gwhite]

Better still, use a .25 caliber rifle brush bent at a right angle to form a handle.

http://www.targettalk.org/viewtopic.php ... 96#p186896

Most common cleaning solvents won't get rid of ancient baked on carbon. In order of increasing effectiveness, I have used:

1) Bore Tech Rimfire Blend
2) Bore Tech C4 Carbon Remover
3) Sharp Shoot R Carb-Out

If you have a borescope and can still see carbon residue, using a MILD abrasive will get rid of the last bits. I put JB Bore Paste on a stack of several .22 VFG felt cleaning pellets on a rod, and scrub in & out. If all else fails, you can try the same approach with Flitz Metal Polish. It's more abrasive than JB Bore paste, but a lot more gentle than other metal polishes.

[lognom]

I'll try cleaning the chamber. I didn't do that yet. I'll also try the spring stretch too.

Thanks,
Lloyd

[spektr]

Dont do the spring stretch until after the cleaning. If you do both and all it needed was a cleaning, The higher firing pin velocity mayshorten the pin life of break it.

[lognom]

Hi,
I tried everything recommended here including cleaning the chamber with Sharp Shoot R Carb-Out and .25 caliber Otis brushes, replacing the hammer spring, cleaning the slide and frame, and polishing the feed ramp. I've tried different ammo and the firing pin is intact. Still no go, but then I stumbled on this blog post about the Domino FAS where he states that the magazine is responsible for the light striking, I think the Chiappa FAS inherited the flaws of the Dominoo FAS.

http://bullshooter.blogspot.com/2006/06 ... autos.html

He recommends oiling the rounds in the magazine. At the range I noticed the first round in the magazine generally would fire but the other rounds wouldn't so somehow the magazine is responsible. Also if I put a round in the chamber and closed the bolt, without a magazine in the pistol, the round won't fire. Is that normal? The light strike problem existed when the gun was new but but has only gotten worse.

I'd take up the issue with Chiappa service but they're hard to get ahold of, to say the least.

Lloyd

[JamesH]

Sometimes the issue is weak recoil spring, the recoil spring on the FAS602 had to be changed regularly.

Weak recoil spring, weak hammer spring, lightweight hammer, short hammer travel, peened over chamber at the ejector cutout, dirty chamber, weak hammer strike, non-ideal firing pin design, draggy magazine,soft firing pin metal, non-euro ammo all conspired to cause light-strikes in the FAS

For some people the key was to profile the tip of the firing pin into an arc, or angle it so more of the impact went into the priming compound and less into the absolute edge of the case which is hard to crush.

That said I had a late model FAS602 which worked fine for years.

[lognom]

Thanks. I'll try replacing my recoil spring next time I go the range. Also, in the targettalk archives, someone with a Domino FAS said he lightly lubricated the magazines with WD40 before use and never had a misfire. I'm going to try that next time too.

[deadeyedick]

Had the same problem with my 602….change the hammer spring and forget the rest.
I think I used a Wolff s@w hammer return spring…about 15 lbs or more.
Spring length should be 31 mm.

[lognom]

I'll try another hammer spring.

Lloyd

[Gwhite]

Thanks. I'll try replacing my recoil spring next time I go the range. Also, in the targettalk archives, someone with a Domino FAS said he lightly lubricated the magazines with WD40 before use and never had a misfire. I'm going to try that next time too.

I would avoid WD40 on any firearm except if it got caught in a flood. "WD" stands for "water displacing", and it does a good job of getting water out of things.

WD40 is not a particularly good lubricant, and when it dries, it leaves a gummy residue that can glue small mechanisms together. Locksmiths love it, because customers use it on locks. They then have to call the locksmith when it seizes up the pins & springs inside.

Pardini USA recommends oiling the top round in every magazine using FP10. I've rarely found oiling the rounds in a magazine to be useful for anything but a diagnostic technique. I didn't have any FP10, and tried RemOil once. The oil got cooked, and the residue in the chamber quickly made things much worse.

[lognom]

O, I'll skip the WD-40. I was going to try oiling the top round but after what you said, maybe I won't.

[Gwhite]

O, I'll skip the WD-40. I was going to try oiling the top round but after what you said, maybe I won't.

If oiling the top round helps, you probably have a dirty chamber. Running a .22 bore brush (especially a worn one) through the barrel will NOT adequately clean the chamber.

Check out: viewtopic.php?p=317263#p317263

[lognom]

Gwhite,

Thanks. However, I've already followed your chamber cleaning instructions to the letter (Otis .25 caliber brush, Carb-out, examine with borescope,etc.) and that didn't help. The one cleaner I haven't yet the tried is the paste.

Can you guess why generally the first round in the magazine will fire, but subsequent rounds won't. Is that a helpful clue or hint what the cause is? The magazines and the gun are fairly new.

Lloyd

[fc60]

Greetings,

A similar issue with my FAS603 (32 WadCutter).

The recoil spring had weakened to the point the slide would not chamber a new cartridge once the chamber started to foul.

A new recoil spring cured the problem.

If you have a known new spring, remove the spring in the pistol and compare the lengths. If the old spring is tired it will be quite obvious, as it will be much shorter in length.

Cheers,

Dave

[lognom]

I have spare FAS recoil springs. but in my case, the slide will chamber the subsequent rounds but they'll light strike and so not fire.

[deadeyedick]

How did slide return springs get into the conversation. I went back and the OP said that several bullets wouldn’t fire not that they failed to load.

If the hammer spring is changed your problem of rounds not firing will go away.
It is a daunting task disassembling the trigger box however it transforms a paperweight into a fully functioning pistol.