Recoil Spring weight for 9 mm STI

[shooterrdy]

I am sure this has been covered, probably beat to death but I am curious as to what shooters find in changing the recoil spring rates for 9 mm STI 5" Marauder, Edge, Eagle style pistol

I have a 135 grn. BBI loaded with 4 grain of CFE Pistol, chronograph says 959 FPS avg. or 129 Power Factor, current spring is ISMI 11lb. silicon

would a lighter spring soften recoil?

would a 12.5 increase felt recoil?

any advice or experience appreciated. Thanks

[jcc7x7]

I run 9lbs springs in both my 9's and they feel very soft to me.

Get a 9, 10 and 11 lbs spring, a couple hundred rounds of ammo and your timer and go and do some standard drills with the different wgt springs and see if it makes a difference in your splits with the different wgts etc. ( make sure your shooting A's or there will not be a true comparison)

[billdozer]

Matts out if it requires alphas!

[Jammer1911]

Running a 10# in my Fusion Semi Custom

[Scott Steele]

9#

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[leath4m]

10 pound, 38 super Edge shooting minor.

[shooterrdy]

Well guess I need to get a 9 lb. and give some a try Thanks all

[oak hill]

I run 9lbs springs in both my 9's and they feel very soft to me.

Get a 9, 10 and 11 lbs spring, a couple hundred rounds of ammo and your timer and go and do some standard drills with the different wgt springs and see if it makes a difference in your splits with the different wgts etc. ( make sure your shooting A's or there will not be a true comparison)

Great advice

[mach1soldier]

I'm thinking you could go lower. I was around 9 for Minor PF and prefer 11-12 for 155 PF (bowling pin load).

[shooterrdy]

must say the 9 # feels pretty good had been running an 11# I think a 10 would be good as well, gun came with a 10 not sure how true to weight any off them are but other than the 10 all are ISMI silicon treated gonna give the 9 a run for awhile.

also Installed a Nitro Finn thumb rest so got a whole new feel now.

Thanks again for all replies , (except 1)

[Chris1911]

I have three STI 1911's, a five inch, a 6 inch and a 5 inch with a 6 inch barrell with a weight on the end. I use a 9lb in all of them.

[Steve RA]

Fairly stock 1911 9mm - 10lb Wolff variable rate. Seems to work well with any load i've tried in the gun.

[Jaxshooter]

I run a 9 lb conventional recoil spring.

[mwc5]

Another 9lb spring in an STI

[v1911]

are we recommending an ISMI 9# or Wolff 9#?

Personally, I use Wolff, but was looking to experiment with ISMI. I know there's a world of difference between the two when it comes to mainspring. Just comparing the two for recoil spring, the ISMI is several coils shorter.

[ltdmstr]

I use 9lb. Wolff standard (not variable) springs in 9mm 1911s.

[t0066jh]

I run 9lbs springs in both my 9's and they feel very soft to me.

Get a 9, 10 and 11 lbs spring, a couple hundred rounds of ammo and your timer and go and do some standard drills with the different wgt springs and see if it makes a difference in your splits with the different wgts etc. ( make sure your shooting A's or there will not be a true comparison)

I think this is the best advice. Not only are the times of your splits important, where is your second shot (on a USPSA target)?. If it's high, not enough spring to bring the recoil back down. If it's low, too much spring. The variables are power factor, (determined by, bullet weight, and bullet speed), and, very important, how tight you are gripping the gun. just my humble opinion.