[brockgl]

I would like to change the Mainspring Housing on my Springfield Mil-Spec to one without the ILS. However, I know that Mil-Spec's use a lighter titanium firing pin to meet California drop test laws. What strength of Main spring to accompany the gun's lighter firing pin? I want the gun to be 100% reliable, but I still like the idea of retaining its drop-safe integrity.

23lb? Any ideas?

[Jim Watson]

I'd use the 23 lb mainspring if keeping the Ti firing pin but not the ILS.

[10X]

I would agree with the 23 lb. main spring.

[Canuck-IL]

Clip 2 - 3 coils off of the FPS and 19#s can be reliable.
/Bryan

[Wvladimire]

You can keep the 23 lb main spring. To pretty much eliminate inertia discharges, they suggest a lighter firing pin, such as titanium, and an extra power firing pin spring. You can get this from Wolff. You don't need to go overbaord only 5-10% extra power firing pin spring. And please, do not clip coils from springs, just get a 19lb MS instead of clipping.

[1911Tuner]

Springfield's ILS mainspring is proprietary to the system, and runs to about 28-28.5 pounds. If you use a standard mainspring, you'll need to go with a standard cap. The cap retaining pin is optional, but recommended.

I also advise using a standard firing pin and spring when making the change from ILS to standard.

[Canuck-IL]

do not clip coils from springs, just get a 19lb MS instead of clipping
The suggestion was to clip the FPS - firing pin spring, not the mainspring. Additionally, the SA mainspring is already short!
/B

[XavierBreath]

Springfield uses a .075 diameter 38 Super/9mm firing pin.

Ed Brown makes the .075" SA firing pins in steel. Their part #826. Brownells (http://www.brownells.com/aspx/NS/store/ProductDetail.aspx?p=1323&title=1911%20AUTO%20FIRING%20PIN) has them or you can buy directly from Ed Brown (http://edbrown.com/htmlos.cgi/00550.1.1142934564317969884).

[Big Daddy Grim]

I am no use here have to agree with the 23

[1911Tuner]

Springfield uses a .075 diameter 38 Super/9mm firing pin.

Yeah...There's that. Actually, it's not exactly the same as a 9mm/.38 Super pin. Ed Brown is the only aftermarket supplier that I know of that offers Springfield's proprietary size pin.

On the mainspring...Stick with 23 pounds. I'm more likely to bump it up to a 25 pound spring than go any lower than 23. When you lower the mainspring's load, you speed up the slide in recoil...causing it to impact the frame harder, and often bring on problems with cartridges "jumping" the magazine.

The mainspring and the recoil spring comprise a balance. Changing one upsets that balance...and changing the recoil spring to compensate only makes it worse.

John Browning and a team of Colt's top engineers burned a lot of midnight oil working out those spring rates. Best leave'em alone.

23 pounds is about right for the mainspring. 15 pounds is about right for the recoil spring...even though 16 has become the accepted industry standard. 16 pounds is a bit much, but it'll do.

Good luck!