So im confused. The 4506 and the 1006 use the same part number through S&W #201610000. So one would assume they are rated for the same pounds. When I looked at the wolff website the 4506 is rated at 14lbs and the 1006 is rated at 18lbs. I bought one from wolff for the 4506 and it is shorter and does not have the same tension when racked. So whats the deal?

There are two recoil springs for the 4506. One is for wadcutters #200710000 and the other is the standard #201610000. Personally, I think that 14# spring noted on the Wolff website refers to the watcutter spring, otherwise the 14# figure makes no sense whatsoever. The actual standard spring is probably 16# to 17#.

Personally, I use a 18# Wolff recoil spring (47318) in my 4506-1 (I only shoot full power 230 FMJ ammo and reloads). And in my 1006, I use a 20# Wolff recoil spring (47620) with my 180 FMJ reloads (1050 fps). They both function perfectly, and sharply throw the spent cases right where I want them.

Good luck.

I mostly use 15# Wolff's & sometimes 16# recoil springs with 200gr. and 230gr. loads. Mostly LRN & LSWC reloads at just barely major PF level. Work well for me.
If shooting heavier, I would use the 16# Wolff. It is a pretty meaty slide, thus no need to go too heavy.
Get a couple of 15# and a couple of 16# and maybe a 17... try em out.
If you hate them PM me and I will buy 'em.

I guess what I was trying to point out is the fact that wolff states the standard is 14 lbs for a 4506 amd 18 for a 1006. But smith uses the same part number for both. So whats the true pounds? 14 or 18? I know I can throw in what ever I want into it. Im just trying to get the correct answer for standard.

The Wolff site in not accurate. Their site also states a 1066 takes a lighter factory standard spring than a 1006, wrong! #14 is the correct factory weight for yours.

Cheers
Bill

__________________
Because they don't make a .46

14 lbs does not make sense. Spring #201610000 is standard in the 4506 and the 1006. I dont see the 1006 running with a 14lbs spring. So whats the true weight of spring number 201610000?

14lb

Just as all the 4.25 inch guns in both 10mm & 45 also run the same 17lb spring pn: 895240000, all the 5 inch guns use the same 14lb spring pn: 201610000. If I'm not mistaken, I believe the wadcutter spring for the 4506, pn: 200710000 is a 12lb.

All these gun have very heavy slides. During firing the slides and barrels are locked together for about the first quarter inch of rearward travel. While the barrels are nearly identical dimensionally on the exterior ,the 10mm barrels are a good deal heavier due the the extra wall thickness. Thus the reciprocating assembly on a 10mm gun is heavier than that of an otherwise identical 45 model. In simpler terms the top end assembly from 1006 weighs more than that of a 4506. This is why the 14# works in both guns.

Cheers
Bill

__________________
Because they don't make a .46

Thank you very much sir. Now it makes sense. Since I have you here I got a second question. Does the length of the spring make a difference? I bought the wolff 14 for the 4506 but its much shorter then the original. When raked it feels weaker the the original and I can feel tue slide battering the frame more. Is it in my head? Or does wolff use the wrong by using a shorter length?

Well Sir, there are a number of things that govern how much muscle a spring has or more accurately, how much energy a spring can store & release. To be sure, the length is very important in making sure a given recoil spring is the correct fit for a particular weapon. In addition to length, we have the coil count, the specific steel allow used to make the wire and wire shape that determines the muscle.

I don't know what spring was originally in your 4506 but for the sake of discussion I'll assume it was a factory 20161. If the new Wolff spring you got is significantly shorter and weaker than the used spring you took out, I'd venture Wolff sent you the wrong part.

You mention you can feel the slide battering more with the new Wolff spring. Well, If your gun is sprung correctly for the loads you're using there should be no battering at all. You'll no doubt get plenty of advice to use an extra power spring of this or that weight. What I'll tell you is to be careful messing with extra power springs. Use a spring that's appropriate for the loads you're using and nothing more. Heavy extra power springs... Slide/frame battering is eliminated but... All that stored energy has to be dumped into something. That something is your locking lugs, barrel cam and slide stop cross pin as the slide is violently flung back into battery. Those are the bits that are now getting battered when using heavy springs beyond the design limits of the gun. Granted it may take a while but what you eventually wind up with is loose lockup, poor accuracy and head space growth.

What I suggest is call S&W directly and see if they have some 20161 springs on hand. Often times I've called S&W and been able to order parts that have been out of stock at all the regular suppliers. Just might be worth sitting on hold for a bit

Anyway, get you a fresh stock factory spring in there and use that as a baseline to determine what your gun needs. Run some standard pressure 230g loads through and if there's no battering or function problems, you're good to go. If you sense any slide/frame battering try a 15# spring and so on. Not every one of these guns behave exactly the same. What works in my gun may not work for yours or for the loads you're using.

Ideally you want full travel of the slide with the spring bringing the slide to a halt just as it kisses the frame then sending the slide back forward into battery. You don't want any short stroking or feeble ejection either. Keep a weather eye on how your gun ejects the brass too. That's an warning warning sign of either a too weak or worn out recoil spring when your empties are landing in the next county.

Forgive me for the long winded reply, I hope you find some of it useful.

Cheers
Bill

__________________
Because they don't make a .46

Thank you very much. It was all useful. I'll be buying a few different weight springs and seeing what works.

Recoil springs {compression springs} are measured at x LBS at installed height. Free length does not matter.

Tom