Fiocci, continued...and recoil springs

[Dwight Gruber]

Just came back from an afternoon at the range, testing the new recoil spring I put in my 1900 American Eagle, in place of the tired-as-a-noodle original. Turns out, Fiocci .30 Luger operates this action just fine.


Now, frankly, I'm still not sure about that recoil spring, about half the time it doesn't completely close the toggle, like it doesn't have enought poop to finish compressing the firing pin spring. I have the same problem Thor reported with my 1920 Commercial (no ejection, rechambering the empty); even this new flat mainspring seems much weaker than the action of the 1920. Has anybody else noted this in comparison, or do I need to find still another flat recoil spring?


--Dwight

Dwight, I'd suggest checking the fit of your barrelled receiver (without toggle installed) to frame fit (no rubbing resistance) and the same with the toggle assy in the receiver. Even a over tentioned ejector rubbing against the breech block can make a big difference. If all of these area check out OK and your got the new recoil spring from me, feel free to return for an exchange, as these with the flat spring do seem to vary more that the coil type. This is probably why the design was changed in 1906. Tom h.

Tom,

From a design standpoint the flat spring is a designers nightmare.

They are so sensitive to any variation in tolerance and heat treatment.

Spring tension is related directly to width, that is

"to double the width is to double the tension.

HOWEVER THE THICKNESS ACTS VERY DIFFERENT !!

To double the thickness increases the tension by a factor of FOUR, ie:

double thichness = 4 x strength or

to halve the thickness is; 1/2 thickness = 1/4 strength.

And a few points difference in hardness has a very unpredictable result in stiffness.

The reason that coil springs are so predictable is because the drawing process creates a wire of very accurate size and and reproducable results.

My observations.

ViggoG

I really goofed !!!!!

ViggoG