I was impressed, for example, by the interest and experience Tuner has regarding 1911 springs. For what I can tell, it's the only (except someone in Brian Enos' Forums) that keeps data about Colt OEM recoil springs and tell loudly that they aren't as strong as supposed. I like very much spring "stories" too, and I think this little report may results interesting.
One year ago a buyed, new, a Colt 1991 NRM 5". Very good! In about 1800 rounds, usually reloaded by me, I didn't had a single stoppage. Please take note that, for an old my habit, I use a quite relaxed grip.
For many reasons (I like tinkering, I'm a gunwriter specialized in testing gun related products, and my NRM ejected spent cases quite distantly) I've tried sometimes a 16.5 lbs Wolff variable recoil spring and a 16 lbs ISMI. These resulted much stronger than my OEM spring (I think it's a 14 lbs), and in both occasions I got, about one time in every 100 rounds, the same FTF (bolt over rim), exactly what Tuner predicts about too strong recoil spring. And the remedy was the same Tuner suggested: 11lbs Wolff magazine springs, or return to the original Colt recoil spring.
A big applause to you, Tuner, and please... share with us your database about OEM spring weight!
The recoil spring in my NRM Commander was too light and too short. Didn't matter all that much, but it was...
I've got a ton of spring test data... somewhere. I noticed that recoil springs weren't "standard" as far back as 1976, and tested every new Colt and Springfield that I could until about a year ago. I'll dig up the notes and post on it in a day or so. The biggest discrepancy that I found was in the Colt Commanders. "Standard" spring rate is supposed to be 18 pounds, but many went as low as 13.5 or 14 pounds... and this went as far back as one unfired NIB '65 Model LW Commander that had a spring in it that tested at 13.2 pounds. I know that the spring would take a little set and lose some of its original tension over the course of 25 years... but wouldn't amount to more than 10 or 12%, which would have put it at about 14.5 or 15 when new. I've also noticed that many Commanders have function problems with a true 18-pound spring.
One trend that I did notice was when Kimber first flooded the market. Many... but not all... Kimbers were oversprung, with resultant feeding and short-cycle issues. Several years ago, Springfield was installing 16-16.5 pound recoil springs in their 1911A1s... and they suddenly changed that about 10 years ago. At that point, the 5-inch guns had What looked to be Wolff 14-pound springs with as much as 2 full coils lopped off... but not in all the guns. Some had 14-pound springs with 32 coils.
Curious... what?
Tuner - I'm curious whether Wolff recoil springs are generally of the weights they advertise? Thanks, WB
quote:
I'm curious whether Wolff recoil springs are generally of the weights they
advertise?
Nope... They'll vary a little. Wolff springs vary less from advertised rating than ISMI, though. Wolff usually can be counted on to produce within a pound of what it says on the bag. ISMI springs... in my somewhat limited experience vary as much as 2 pounds plus/minus... AS INSTALLED. ISMI springs come out of the package overlength to allow the smith to tune them for length and loading. Dimensional differences within the spring tunnel does make a slight difference... and so will differences in the thickness of the guide rod head. Little things stack up.
When tuning the spring load for best function, remember: More coils with a lighter spring is better than fewer with a heavier spring. If you need to clip more than 2 coils, it's time to drop to the next lower number and start over. F'rinstance...A 16 pound/32 coil spring that's clipped to 28 coils will produce about the same loading as a stock 14-pound spring. If the gun likes a 14 pound spring...use the one with the greater number of coils.
I purchased 10 Nowlin Heavy-Duty firing pin springs for 1911's. Out of the 10, several were a 1/4 inch shorter than the others.
Is this right? They all have the same part number
Dunno Ken... All the Nowlin(Wolff) FP springs that I've gotten are to spec on the length. Series 80 Colts usually have shorter/lighter springs in 'em than
I'd be comfortable with in a standard design pistol... but I've never seen a designating part number on Nowlin or Wolff packages.
I'm as confused as you are...