Mossberg 930 / 930 SPX mag springs

[njl]

I've got a 930 Waterfoul for which I've acquired all the parts to make it an SPX. In its original configuration, it's been 100% reliable except that I generally cannot get it to feed the first round from the magazine. i.e. if I load one into the chamber, close the bolt, load the mag, they all fire/feed just fine. If I load the mag on an empty chamber, the mag won't feed.

In SPX configuration, I've not put many rounds through it, but it's basically the same. Shoots fine...won't chamber from an empty chamber / full mag.

The original spring is 23" and tapered at the follower end.

The spring that came with my SPX parts is 28.75" and not tapered.

Measuring how much spring protrudes from the open mag tube, the shorter spring is 10.75" longer, the longer spring is 17" longer.

I tried assembling it in SPX configuration with the 23" spring, and doing that, it appears it will chamber from a full mag pretty reliably as long as I pull the bolt back with significant force with the stock against my thigh. Once the mag has been downloaded by 3 rounds, it's hard to cycle the action without the mag feeding a shell. i.e. cycling it very slowly/gently still tends to feed a shell most of the time.

I've not tried firing it in this configuration yet. I've read that Mossberg shipped some of the early SPX's with short (23") springs, and that there were "problems" with them, but I haven't seen any details on what the problems were. I've also read of people getting new SPX's with anywhere from 23 to 40" mag springs.

If I want this gun to be reliable but also be able to go from "cruiser ready" to ready to fire without having to manually feed one into the chamber, is more testing with the 23" spring worth a try? Should I go with the longer spring, but cut a couple coils off of it? Is there a "right" length for the mag spring in the 7-round mag configuration? I'd guess the "right" length really depends on the strength of the spring. I've read some are made of thicker material than others.

Where's a good place to get spare/replacement springs? I looked at Brownells and Wolff's web site, and didn't find specific springs for the 930 SPX at either site.

[ChuckS]

A fix for the feeding issue is discussed in the mother of all 930 threads:

http://www.brianenos.com/forums/index.php?showtopic=142693entry1605064

Also, pretty much any other question should be answered there also.

Good Luck,

Chuck

[njl]

Do you mean the bit about removing the shell holder and doing a fluff and buff on it? I've considered doing that...but just below that, he says the mag spring should only extend 10" beyond the end of the tube. That's about where I am with the original spring.

[njl]

I went ahead and removed the shell holder and polished it with some Flitz and a rag by hand. With the longer spring now, if I cycle the action briskly, it feeds from a full mag. Every round after that wants to feed no matter how slowly / gently I cycle it. That's a big improvement. I'm temped to take a couple inches off the long spring, but will probably hold off on that for now.

The hardest part was getting the shell holder pin's clip back in place.