Storm Lake .357 SIG conversion Range Report

[swsig]

As to your OOB problem? Have you chrono'd the ammo? It sounds as if maybe the Sig ammo may be weaker and not retracting the slide to full extension or not hard enough. That's how my problem starts. When my issue first starts, the slide will extract and eject, but I'm thinking it just barely clears the round in the mag enough for it to pop up a little to catch the slide and at this point there's not enough energy in the slide to strip the round from the mag. Or it may be stopped on the front of the mag, these mags don't allow much for for longer cartridge lengths, but with the Sig round I would think it would be clear of the front edge of the mag if it's high enough to stop the slide. Next time out I'll check that.

Hope the wife rehabs good. My wife had a similar problem awhile back. She now has a gamma nail in her femur.

I don't have a chrono, but subjectively, the SIG Sauer ammo doesn't feel or sound any weaker than the others. As I think about this some more, I'm wondering if my problem (as george_lehr suggests in #16) is due to a weak recoil spring assembly. About a year and a half ago, I had a bunch of failures to fire/OOBs with .40 cal. in my 40c. A new RSA completely cured the problem. This (my current) RSA has only about 2,500 rounds on it, so I haven't considered it a suspect. But who knows, I may have gotten a short-lived one. (The previous one cratered around 3,500 rounds.) Next time I go to the range, I'll take the original RSA that came with the 40c and try it out. It never had a failure to feed/OOB in 6,000 rounds. I swapped it out at 6,000 rounds only as a precaution. If the SIG Sauers run perfectly with it, I'll have found the source of my problem. Then I'll hit up S&W for a new RSA.

Now that I think about it some more, I wonder if that may be the source of your problem, too. A weak RSA would cause the slide to move forward with too little force to properly strip the top cartridge from the magazine. I guess that's now my universal solution to all M&P problems: Get a new RSA!

Thanks for your concern about Mrs. swsig. Fortunately, the only treatment she needed was rest and rehab. I don't know what a gamma nail is, but I'm sure Mrs. swsig is glad she didn't need one!

 

[swsig]

With Mrs. swsig now recovered from her pelvic fracture, I was finally able to get to the range yesterday. The six week absence did nothing for my accuracy (Horrible!) with my 13,000 round 40c's .357 SIG Storm Lake conversion, but I did learn more about what might be causing my out-of-battery/failure-to-fire problem.

I fired 40 rounds each of SIG Sauer, American Eagle, and Lawman ammo, 10 rounds of each brand in groups of three. With the first group, I experienced what I had previously. The ten Lawman and American Eagle rounds all fired normally, but I had one FTF with the ten SIG Sauers. I then replaced my current recoil spring assembly with the one that had come with the 40c, which had performed flawlessly for 6,000 .40 cal. rounds. Disaster! Virtually every shot with all three brands ended up out of battery. The many rounds the old RSA had handled had weakened it to the point that it couldn't deal with any .357 round. But this experience strongly suggested that the RSA is the source of my problem.

I put my current RSA back in for the last 60 rounds, and I added more lube (SLIP 2000 Extreme Weapons Grease) to the barrel and slide supports. The final 40 combined Lawman and American Eagle rounds fired perfectly, but I still had about a half-dozen FTFs in the 20 remaining SIG Sauers. My current RSA has 2,700 rounds combined .40 and .357 rounds on it, so it may now have weakened enough to have problems consistently returning the slide to battery. There is also an expanding area of wear on the top of Storm Lake's barrel hood, suggesting that it is not completely broken in, with only 428 rounds so far. (See attached photo.) The resulting drag on the slide may be creating enough resistance that the RSA is not always able to overcome, regardless of how much lube I put on it.

Solution, (I hope!) is a new RSA. I ordered a couple from Brownells last night, and they say they'll be here by Wednesday, which will be in time for me to take them on my usual Thursday range visit. I intend to shoot my new Storm Lake barrel until it is finally broken in and OOB/FTF-free, even if it takes another 13,000 rounds! Stay tuned.

 

[asilcot]

I bought factory 357 Sig barrels for my M&P 40 and the P229. I bought the Sig first and it drove me nuts doing the same thing you described. I absolutely could not get it to close on a reloaded round. It shot factory ammo flawlessly although I only tried three brands. When I bought the M&P I had a box full of rejects that would not cycle in the 229. I loaded them in the M&P and shot all of them with no failures. Both 357 barrels are very accurate. I think this is inherent with the 357 Sig cartridge.

The S&W factory 4.25" barrel is still available and in stock at Midway. The 3.5" is still a mystery. I have the part number and called S&W yesterday. Told the lady I had a part number and wanted to check availability. Gave her the part number and she said "You want to buy a BARREL?". Pretty much told me that they do not sell barrels or slides to riff raff and the conversation headed downhill from there. Before she hung up I asked whether the part was even still being made. She said it is still a valid part number but availability would not show in inventory because (refer to "riff raff" above). Guess I will have to go Storm Lake if I pursue the conversion for the 40C.

 

[STORMINORMAN]

I'll jump in and opine that there is no reason I can see that either of the two 4.25" 357 Sig barrels, either the factory one @ Midway for $90 (!) & still available (a Thanks! to asilcot as above) or the StormLake conversion wouldn't work just fine in one of the new M&P 2.0 Compacts with the 4"barrel option. The "extra" .25" is IMHO negligible...

A 5" 9mm StormLake conversion works just fine in a 4.25" M&P frame: that's an "extra" .75" and the "raised portion of the barrel" is an inch + 1/4 long on mine. Lockup is excellent, as is accuracy.

Cheers!

P.S. Sportsmens Outdoor Superstore has the 40 S&W M&P 2.0 Compact 4" without safety (Model 11684) for $299: subtract the $40 S&W rebate (Military & LEO, I believe?), hit Midway for a $90 barrel and for $350 you have a brand new M&P in two calibers! Has to be one of the BEST DEALS EVER!

 

[swsig]

I was back at the range today with my 40c Storm Lake .357 SIG conversion, and a new factory recoil spring assembly. The first thing I noticed was how much stiffer the new spring was. 2,700 rounds had taken its toll on the old one for sure. I fired 50 rounds of American Eagle FMJ: Perfect. I fired 50 rounds of Gold Dot HP: Perfect. I fired 40 rounds of the problematic SIG Sauer FMJ: Perfect. I thought my strong new RSA had cured my out-of-battery problem. Then I fired the last 10 rounds of the SIG Sauer ammo: Four out-of-batteries! Bleah! Very disappointing.

I now have 578 .357 SIG rounds through this barrel, plus a new RSA, and my 40c conversion still can't handle SIG Sauer ammo. That's the bad news. Fortunately, the SS stuff is only target ammo, so I can simply not use it at the range. American Eagle and Lawman (both perfect so far) will do just fine. But the really good news is that the conversion has been perfect through 100 rounds of Gold Dot self-defense ammo. Perfect functioning with self-defense ammo is the most important aspect of any carry gun. If it stays perfect through another 100 rounds of Gold Dot, I'll have enough confidence to start using my 40c conversion as my everyday carry.

Overall, I'm very satisfied with my Storm Lake barrel. If it shot SIG Sauer ammo as reliably as it has with the other brands. I'd give it a solid A. Even with its limitations, I'll still give it a B+. I'll continue to update this thread as I progress through future range sessions.

 

[ShivasIrons]

357 Sig is a great round. great to see people shooting it and keeping it alive. I have shot a fair amount of it over the years, but for some reason, never ended up owning a handgun chambered for 357 Sig.

A quick note about recoil and the 357 Sig. The First time I shot a 357 Sig was when the VA State Police adopted it. A friend was a Trooper and I was running some rounds through his Sig. At first, I thought the recoil was pretty stiff. Then, after a few mags, I noticed it was muzzle blast and not truly recoil. The recoil impulse and rise was less than the 40 I was shooting. Pay attention to that the next time you shoot 357 Sig and see if it makes a difference.

 

[Ivan the Butcher]

This is the first time I've seen this thread. In looking at the photo of the replacement barrel's wear pattern, it looks to me that you barrel slide fit is off in that area of contact. I have an older Sig 229 with a round count in the 7000 range! The wear in the lockup area is even and only at the outside edges (Both on the top and sides of the barrel!) About 50% of the ammo used is the Ranger LEO ammo, the other 50% is Speer Lawman.

I see two solutions: fit the barrel at your expense or return it for manufacturer's warrantee replacement. ("Do Nothing" and "never use Sig ammo" are options that you indicated won't be considered.) You should consider if your lubrication includes this area on the inside of the slide.

I'm interested on how this plays out. I've never been a fan of 40 S&W but many department are leaving that round to go back to 9mm. So, I've been thinking of doing the exact conversion you've done. (Since I really like the 357 Sig round!)

Ivan

 

[swsig]

This is the first time I've seen this thread. In looking at the photo of the replacement barrel's wear pattern, it looks to me that you barrel slide fit is off in that area of contact. I have an older Sig 229 with a round count in the 7000 range! The wear in the lockup area is even and only at the outside edges (Both on the top and sides of the barrel!) About 50% of the ammo used is the Ranger LEO ammo, the other 50% is Speer Lawman.

I see two solutions: fit the barrel at your expense or return it for manufacturer's warrantee replacement. ("Do Nothing" and "never use Sig ammo" are options that you indicated won't be considered.) You should consider if your lubrication includes this area on the inside of the slide.

I'm interested on how this plays out. I've never been a fan of 40 S&W but many department are leaving that round to go back to 9mm. So, I've been thinking of doing the exact conversion you've done. (Since I really like the 357 Sig round!)

Ivan

I changed my mind about SIG ammo. Since I don't have to use it, I won't. As long as my Gold Dots continue to cycle perfectly, that's all I need. I figured some wear on the hood might occur because each slide an aftermarket barrel would have to fit will be slightly different due to pre-existing wear patterns. Initially, I lubed the hood to S&W's minimalist specs, but after the continued wear, I began to lube the heck out of it. The wear pattern seems to have stabilized. The first photo below is the one I posted previously, and the second one is after yesterday's 150-round session. I can't see much change. For further comparison, the third photo shows my original .40 cal. barrel with over 13,000 rounds. I'm looking forward to seeing how this all plays out.

 

[Wee Hooker]

If you find the 357sig's recoil too stout, you can always "bloop" it out of the 40S&W barrel. It will hardly recoil at all . Keyholes the heck out of the target though. Ask me how I know?

 

[Ivan the Butcher]

With the photo of the OEM barrel it shows that the replacement barrel is too thick on the foreword slope over the chamber. It is not only wearing the barrel, it wearing the slide also. I personally, would stone it down a 1/10,000" or two, but I believe a trip back to the manufacturer is in order. But that is me. Have fun and please keep us posted.

Ivan

 

[asilcot]

I figured some wear on the hood might occur because each slide an aftermarket barrel would have to fit will be slightly different due to pre-existing wear patterns. Initially, I lubed the hood to S&W's minimalist specs, but after the continued wear, I began to lube the heck out of it. The wear pattern seems to have stabilized. The first photo below is the one I posted previously, and the second one is after yesterday's 150-round session. I can't see much change. For further comparison, the third photo shows my original .40 cal. barrel with over 13,000 rounds. I'm looking forward to seeing how this all plays out.

Possibly a case of tolerance stacking. The barrel hood is at the large end but within spec. The ejection port in the slide may be at the small end of acceptable. The two combined may result in the tight fit. I am sure Storm Lake would buff it down a little to take care of it but that is your call.

I just received the same barrel in the mail today. Weather permitting I hope to get to the range with it tomorrow. I will let you know how it looks after a few rounds.

 

[swsig]

...I just received the same barrel in the mail today. Weather permitting I hope to get to the range with it tomorrow. I will let you know how it looks after a few rounds.

I'll look forward to that.

 

[TAROMAN]

I had one Storm Lake barrel.
The thing was so short throated that not one round that passed the tight Shooter's Box gauge would plunk and spin.
Not wanting to throw good money after bad, I threw IT onto the junk box.
If you haven't heard, Storm lake was taken over by the firm that controls Remington.

 

[BigDaddy7972]

I have a Glock 23 and two Storm Lake conversions to 357sig and 9mm. I think the accuracy is improved over the stock Glock barrel.

Is this an everyday carry for you? I ask because I also picked up a 40 to 9 Storm Lake barrel for my G23. I've shot about 1k rounds through it without a single failure yet other people tell me that it's an unsafe thing to do. Your thoughts or anyone else's for that matter.

 

[Mahalo_.32]

I have a 357sig barrel in my 40c from Storm Lake and I have a factory 357sig barrel in my FS 1.0 neither of them have any issues with WWB, Fiocci, Federal, AE, Lawman, Gold Dot or Underwood. I do have similar wear marks on my Storm Lake barrel but that is to be expected since aftermarket barrels tend to have tighter clearences. If I had no issues with a few brands of ammo and 1 issue with another that ammo will stay out of rotation for that firearm... Your M&P is a very reliable firearm. The 357 sig was discontinued by S&W because the market for that caliber 357sig was NOT strong enough for them to continue. I have shot countless rounds of sig with NO MALFUNCTIONS with the previously stated ammo in either of my 2.....
A little more cash into my gun fund piggy bank and I will have my new 2.0 which will have a brand new sig barrel to boot.
Glad to see more people keeping the 357sig alive

 

[asilcot]

I'll look forward to that.

I made it to the range today. Shot about 100 rounds through the Storm Lake barrel. Only 5 were factory (Speer Lawman 125 gr Gold Dot). The rest were cast reloads. No malfunctions. Photo attached to show barrel wear at the end of the day. For velocity comparison the Speer Gold Dot five shot average from the P229 was 1289 fps. Same ammo through the 3.5" Storm Lake was 1222 fps across my Oehler 35 P.

For reference the reloads were 125 grain cast powder coated. Five shot average of 1211 fps.

 

[asilcot]

I had one Storm Lake barrel.
The thing was so short throated that not one round that passed the tight Shooter's Box gauge would plunk and spin.
Not wanting to throw good money after bad, I threw IT onto the junk box.
If you haven't heard, Storm lake was taken over by the firm that controls Remington.

Thanks for this reminder. When my Storm Lake barrel arrived yesterday I opened it, cleaned it and checked to see that it would fit in the gun and close properly. After what I went through with the P229 I assumed that the ammo I am loading would shoot in ANYTHING. After reading your post I went out to the shop at midnight last night to make this vital check and the ammo would not chamber in the new barrel. I went over to the reloading building and grabbed my case gauge (the same one you have). My ammo would not go in the gauge. Checking my Dillon 550 I found that the lock nut for my Lee FCD had loosened and the die had backed off. I adjusted it, recrimped five rounds and checked the fit in the gauge and then in the gun. All was well then except that I had to recrimp almost 200 rounds. I finished up about 1:30 this morning. Better then and at home than finding out when I got to the range today.

 

[swsig]

I made it to the range today. Shot about 100 rounds through the Storm Lake barrel. Only 5 were factory (Speer Lawman 125 gr Gold Dot). The rest were cast reloads. No malfunctions. Photo attached to show barrel wear at the end of the day. For velocity comparison the Speer Gold Dot five shot average from the P229 was 1289 fps. Same ammo through the 3.5" Storm Lake was 1222 fps across my Oehler 35 P.

For reference the reloads were 125 grain cast powder coated. Five shot average of 1211 fps.

Good to see that you have wear marks on your hood in the same places as those on mine. They're not the same shape, but at least I know that what I'm seeing on mine is normal. Thanks for the photo!

 

[CB3]

I made it to the range today. Shot about 100 rounds through the Storm Lake barrel. Only 5 were factory (Speer Lawman 125 gr Gold Dot). The rest were cast reloads. No malfunctions. Photo attached to show barrel wear at the end of the day. For velocity comparison the Speer Gold Dot five shot average from the P229 was 1289 fps. Same ammo through the 3.5" Storm Lake was 1222 fps across my Oehler 35 P.

For reference the reloads were 125 grain cast powder coated. Five shot average of 1211 fps.

Two questions:

Aren’t those 9mm + 100 FPS velocities?

And isn’t a critical lockup surface of the slide causing the wear mark pictured, thus indicating slide wear that should be concerning? Either the barrel is not dropping far enough to let the slide pass over it without wear/friction, or that part of the barrel hood maybe should be reduced, as I don’t think it effects lockup.

 

[asilcot]

Two questions:

Aren’t those 9mm + 100 FPS velocities?

And isn’t a critical lockup surface of the slide causing the wear mark pictured, thus indicating slide wear that should be concerning? Either the barrel is not dropping far enough to let the slide pass over it without wear/friction, or that part of the barrel hood maybe should be reduced, as I don’t think it effects lockup.

I don't want to sidetrack the thread but there is a discussion from American Rifleman here: American Rifleman | 9 mm versus .357 Sig
An excerpt from that article: "There is an enormous array of 124-grain ammo in 9 mm, including some +P and +P+ that is extra hot. The average velocity for all loads at this weight is about 1,100 fps. Now look at the average velocity of an admittedly smaller assortment of .357 Sig ammo using bullets of the same weight. It is approximately 1,350 fps. In other words the typical 125-grain JHP load travels 250 fps faster in a 357 Sig than in a 9 mm Luger. In the 147-grain bullets, the 9 mm drives bullets to about 1,000 fps, while the .357 Sig does about 1,225, some 125 fps faster. There is a clear speed advantage to the Sig, not at all surprising in view of the larger case capacity."

My reloads are low end starting loads for 357 Sig and the Speer LE load is certainly not max available for factory loads.

Regarding the contact between the barrel and the slide, I do not think this is a serious problem because as you said, this area does not affect lock up. This marking would indicate some contact with the lower corner of the opening in the slide but I do not think it would be enough to cause significant wear. I may contact Storm Lake to inquire about it. It is a little more than the factory barrel shows in the full size M&P.