I need some guidance/advice. I have been trying to fix a problem with my O/U shotgun (a Fausti Stefano Elegant)...consistent light strikes and failure to fire on the top barrel. I've narrowed it down to possibly a small spring that sets the sear loosing it's temper and bending causing it to not work properly. When the sear does set, on release the hammer and sear maintain a firm contact, slowing the hammer down, causing a light strike...I think. A new spring will tell me. Any further suggestions?

Sounds reasonable. Check the firing pin channel for dirt, etc, too. I've seen that a few times, but mostly with concealed carry handguns.

check its closure isnt hampered by build up of crud.....
maybe try your world famous 2stroke petrol soak/cleanse.

Definitely no crud guys. All parts move freely and smoothly in their relevant positions. I normally only lubricate the action with graphite. I have pulled the entire action apart (about a thousand small 'bits and bobs') and cleaned each part, plus the body of the action etc individually using near enough a full can of Brakleen to thoroughly clean the action and all parts.

I've bitten the bullet and ordered two new sears and associated springs...they come as a single item/part...through the Aussie Fausti agent. Pretty happy with the price, $50 plus post. Should have them by the end of the week. Looking at the original parts, there doesn't appear to be a need to do any fitting as the parts are case hardened and should come ready to drop in.

good stuff mate...hopefully end of your issues.

I've often wondered why no-one has developed a gauge for measuring firing pin strikes !!!

Almost every serious shooter I know has encountered some sort of issue centered around firing pin force, myself included.

It sounds like you got it figured out Vince.
The fact it only happens in the top barrel pretty much eliminates the ammo.
Had a bad batch of primers once, was convinced it was the gun until I shot some different ammo.

Vince,
How far out of the breach face does the firing pin protrude?
Firing pin not worn or chipped?
Cheers

Lost Chambered wrote:

I've often wondered why no-one has developed a gauge for measuring firing pin strikes !!!...

I think every shooter I know uses the old Mark 1 eyeball method by inspecting the indentation in the primer to see if it is a good strike.

I've tried all sorts of methods to "measure" or "record" firing pin strikes mate. Plasticine in the primer pocket, playdoh in the primer pocket, spent primer with the old strike indentation hammered out. I even tried a simple couple of pieces of paper (to see if the pin pierces it). None of them provide what I would call a consistent or measurable strike that I would trust, although the piece of paper to check if it pierces was probably a reasonable indication of sufficient strike.

I would imagine something along the lines of a "snap cap" with a method to record the length or amount of movement of the spring loaded cap might work. Another option would be a pressure type switch and a battery powered LED that would light once sufficient force is applied to the switch. This wouldn't actually measure the strength of the strike, just tell you if it was a hard enough strike to detonate a primer.

dhc4ever wrote:

Vince, How far out of the breach face does the firing pin protrude? Firing pin not worn or chipped? Cheers

Firing pin is good Pete...I replaced it about a couple of thousand rounds ago. The protrusion is heaps, if anything a tad more than the bottom barrel that consistently fires.

I decided to experiment a little with the spring and attempted to re-temper the little bugger. Firstly I ensured it was straight and coils were even, then I heated it up to cherry red then dropped it into a container of vegetable oil. Fitted it back into the action and tried it...damned if it didn't work like a champion...but I don't trust it so it will be replaced when the new parts arrive later this week. It will sit there as a spare or an example of size in case I need to get one made to buy another.

Good luck with it Vince
You are a braver man than me
I always end up with spare parts and a non functioning firearm

Nice trick with the spring! I've got a revolver now (Ruger Security Six I got in the late '70s) that may have a weak hammer spring. Like you, however, I think I'll just order a new one.

Vince,
I like a story with a happy ending. All the best...
Gil

Tiks wrote:

Good luck with it Vince You are a braver man than me I always end up with spare parts and a non functioning firearm

There's nothing difficult about it mate, just have to keep your wits about your and make liberal use of the camera so you have pics of what it all should look like. I am used to dismantling firearms from my time in the Army so I suppose it is sort of second nature to me. I'm also fairly mechanically minded, so again, it wasn't overly difficult. The two things I always do though is take pictures, and when dismantling, lay things out in order. I use a sheet of cardboard (a pizza box works real well), poke holes in it, write the name of the part beside the hole, including LEFT or RIGHT, and push the parts into the holes so they don't move or get mixed up. Come time to reassemble, it's simply a matter or reassembling in reverse order.

As an aside mate, have you seen the latest Tikka bits Cleavers have for sale? Unimag II

Pumpkinslinger wrote:

Nice trick with the spring! I've got a revolver now (Ruger Security Six I got in the late '70s) that may have a weak hammer spring. Like you, however, I think I'll just order a new one.

Wolff make a complete spring kit for most revolvers Punkin and they are reasonably priced (or they used to be) and improve the action no end. I had a Wolff spring kit in my S&W 586 and it was great.

Wolff Springs

Gil wrote:

Vince, I like a story with a happy ending. All the best... Gil

Thanks mate. Not quite at that happy ending yet, but if Australia Post does their bit, things should all fit into place by Friday this week.