Sig 220 Recoil Spring

[Taio]

The original recoil spring for the Sig 220 (and Browning BDA) was 15 lbs. Unless I am mistaken, the bulk of the excellent reliabilty reputation was formed during these years. In the 1990s, the recoil spring was increased to 20 lbs to help with the more popular +P loads. This stronger recoil spring has always seem stiff to me, especially compared with my Colt 1911 and it's 16 pound spring. What I have found with the 20 lb spring is that when using full power, 230 grain bullets, it has very fast slide velocity. If my mags are starting to get dirty (near the end of a shoot), or if I have a spring that is getting a little weaker, I will get a failure of the slide to lock open, or even pass over a round in the magazine. With my mid range reloads, the slide is a little slower, giving the rounds in the magazine to get in proper position.

My question (sorry to took too long to get to it) is this: Will an 18 lb spring give my slide a little more "dwell" time in its rear position, and be more forgiving on my magazines and bullet position. 18 lbs is less than factory, but still 3 lbs heavier than the original 15 pound spring, so I would think I would not have any increased wear on the Sig. What do you think?

[ghostrider]

Taio:

I believe that the 18 lb. spring would actually give you more rearward slide velocity. If your cases are dinged near the center from hitting the ejection port, I wouldn't go to the lighter spring. What I found on my 220 is that slower burning powder like AA#5 gives me more usable velocity without too much slide velocity. I use 8 grains with a 200 gr SWC and 7.5 (0.2 under the starting load) for a 230. I have been up to 8.5 gr.(right at 1000 fps) with the 200 gr HC before seeing the effects of too much slide velocity.

[n2299]

Taio, instead of going to an 18lb spring why don't you just try the "old" 15lb recoil spring. I belive a lighter spring does give you the extra "dwell" time you're looking for.

FWIW I use a 14lb spring with my 9mm P220 and have never encounter a problem.

[Taio]

I went out last weekend with the Sig 220 and the Wolff 18 lb recoil spring. After putting 100 rds of Fed. 230 hardball and 50 rds of my reloaded 200 SWC through it, I have to say I was impressed! The recoil seemed smoother, ejection seemed just as positive as with the 20 lb spring, and it felt like a more "natural" weight of spring. I'll save the 20 lb spring should I get the hankering for some +P loads.