Storm Lake .40 to 9mm Comp. barrel tolerance issue - MP-Pistol Forum

Storm Lake .40 to 9mm Comp. barrel tolerance issue

This is a discussion on Storm Lake .40 to 9mm Comp. barrel tolerance issue within the MP Pistol Tech Help forums, part of the Smith & Wesson MP Forum category; I've been pining for a .40 to 9 conversion barrel for my M&P40c for a while now. Everytime I go to order one, however, it's ...


Go Back   MP-Pistol Forum > Smith & Wesson MP Forum > MP Pistol Tech Help

Reply
 
LinkBack Thread Tools Display Modes
Old April 22nd, 2015, 06:11 PM   #1
Junior Member
 
Join Date: Nov 2013
Location: Texas
Posts: 17
Storm Lake .40 to 9mm Comp. barrel tolerance issue

I've been pining for a .40 to 9 conversion barrel for my M&P40c for a while now. Everytime I go to order one, however, it's always out of stock. I got lucky this past weekend and managed to order the last one grabagun had (only moments after they got it back in stock). I ordered some 9mm mags from gregcotellc, and couldn't wait to tear open the package when it arrived.

I immediately stripped down my M&P, took out the factory barrel, and set about installing the Storm Lake conversion barrel.

Only one problem: it doesn't fit.

The top of the barrel doesn't quite seem to fit into the ejection port. I can't slide or force in.


I emailed them yesterday, but I haven't gotten a response back yet. I plan on trying to call them tomorrow to see what they say. On their web-page it says that their M&P barrels are "drop-in" replacements ,and only "occasionally" require gunsmithing. Has anyone had experience dealing with Storm Lake customer service? Do they replace/fix barrels barrels, or do they tell you to take it to a gunsmith? Last time I tried to buy a replacement barrel I had to send it in (S&W OEM .357sig), and they had my gun for about 9 weeks or so. I don't have much luck with aftermarket parts.

As an aside, I just happen to be a beginning engineering student, and I was curious as to what degree the barrels differed. So I pulled out my cheapo digital caliper that I use for hobby-CAD stuff, and I took 5 measurements of said dimension, averaged it and compared it with my OEM .40S&W barrel. I was rather surprised and intrigued by the result.



My caliper measures to 1 millionth of an inch, but you're only supposed trust up to 1 thousandth of an inch, so ~1.220" (Storm Lake) and ~1.213" (S&W),.... They differ only by 0.007", barely perceptible when comparing them side-by-side! When measuring the ejection port, I got an average of 1.222", Storm Lake's tolerance leaves only 0.002" of an inch of clearance (obviously not enough in my case), and Smith and Wesson leaves 0.009" of an inch in clearance. I've read that Storm Lake uses tight tolerances, and they weren't kidding.

I took multiple comparison measurements between the two barrels, and nearly every time I got the same reading on the Storm Lake barrel, but when I measured the Smith and Wesson barrel, the measurements varied sometimes significantly across the same surface, (+/-0.002"). I don't have a lot of experience machining, nor have I taken a class dealing with manufacturing tolerances, but I'm rather surprised at how much of a difference a few thousandths of an inch makes, especially in a handgun. I hear about pistol tolerances on gun forums all the time, but this is the first time I've personally seen an example of it. Go figure.

Last edited by sittinduck21; April 22nd, 2015 at 06:18 PM.
sittinduck21 is offline  
Old April 22nd, 2015, 06:53 PM   #2
Senior Member
 
jasonuscg's Avatar
 
Join Date: Dec 2009
Location: Salish Sea
Posts: 4,539
Storm Lake says on their site...

http://www.storm-lake.com/model_sw

Quote:
All Smith & Wesson M&P barrels are drop in and will only occasionally require modification to fit.
jasonuscg is offline  
Old April 22nd, 2015, 07:10 PM   #3
Junior Member
 
Join Date: Nov 2013
Location: Texas
Posts: 17
I am aware of what it says. I was asking if anyone had experience dealing with their customer service, and whether they do the occasional modification or if I am responsible.
sittinduck21 is offline  
 
Old April 22nd, 2015, 07:22 PM   #4
DrJ
Member
 
Join Date: Oct 2014
Location: Missouri
Posts: 81
Quote:
Originally Posted by sittinduck21 View Post
I am aware of what it says. I was asking if anyone had experience dealing with their customer service, and whether they do the occasional modification or if I am responsible.
I bought the factory barrel after reading the modifications needed with the storm lake, but they are great barrels, and most people said that a little bit of filing will do the trick. From what others said, it's a simple fix, but let us know how it turns out
DrJ is offline  
Old April 23rd, 2015, 12:25 AM   #5
Senior Member
 
KRWeiss's Avatar
 
Join Date: Oct 2007
Location: Northwest
Posts: 8,105
Quote:
Originally Posted by sittinduck21 View Post
I was asking if anyone had experience dealing with their customer service, and whether they do the occasional modification or if I am responsible.
Of the several hundred Storm Lake barrels this forum's membership have purchased, only 2 instances of fitment issues have been reported. As I recall, they were both handled promptly and professionally, giving tolerance stacking as the probable cause.

Early last year, a fellow competitor purchased a KKM barrel for his current Limited Class M&P pistol build. Unfortunately, the muzzle was sticking just enough to cause some minor timing issues, but only in this one gun. With his permission I swapped his barrel for an identical barrel I had in my range bag, We're both happy campers, since he now has a barrel that works perfectly in all his pistols, and my muzzle may lock up a smidge tighter than it did before.

P.S. Yes Woodys2718, we already know how you hate it when I use such imprecise language as "minor".
KRWeiss is offline  
Old April 23rd, 2015, 08:35 PM   #6
Senior Member
 
Keeter1911's Avatar
 
Join Date: Jun 2012
Location: Texas
Posts: 2,217
Quote:
Originally Posted by KRWeiss View Post
Of the several hundred Storm Lake barrels this forum's membership have purchased, only 2 instances of fitment issues have been reported. As I recall, they were both handled promptly and professionally, giving tolerance stacking as the probable cause.

Early last year, a fellow competitor purchased a KKM barrel for his current Limited Class M&P pistol build. Unfortunately, the muzzle was sticking just enough to cause some minor timing issues, but only in this one gun. With his permission I swapped his barrel for an identical barrel I had in my range bag, We're both happy campers, since he now has a barrel that works perfectly in all his pistols, and my muzzle may lock up a smidge tighter than it did before.

P.S. Yes Woodys2718, we already know how you hate it when I use such imprecise language as "minor".

P.S. +1 Lol!
Keeter1911 is offline  
Old March 4th, 2016, 03:31 AM   #7
Junior Member
 
Join Date: Dec 2015
Location: Ohio
Posts: 11
I have two Storm Lake 40 to 9mm conversion barrels for my M&P 9's. One works perfect, no problems, the other gives me failure to feed issues. I tried calling their customer service line all day Wednesday and sent them an email Wednesday as well. Sadly, no response from them.
Polaris13 is offline  
Reply

  MP-Pistol Forum > Smith & Wesson MP Forum > MP Pistol Tech Help


Search tags for this page

1.220 bull barrel

,

storm lake barrel doesn't fit

Click on a term to search for related topics.

Thread Tools
Display Modes


Similar Threads
Thread Thread Starter Forum Replies Last Post
Want To Buy: Storm Lake Barrel SW-MPL-9MM-571-01T-T-BK for S&W M&P9L yj93ben Classifieds 0 January 18th, 2015 03:03 PM
Storm Lake 2 port barrel problems Anyone with a Storm Lake barrel and M&P having any Jet Setter MP Pistol Tech Help 8 December 4th, 2012 02:35 PM
Storm Lake Barrel B.K. Deals 0 April 15th, 2010 08:13 PM
SWC's in a Storm Lake .45 Barrel? lgjhn MP Full Size Pistols 3 February 26th, 2010 08:01 PM
Storm Lake Barrel on FS .45 ACP HungrySeagull MP Pistol Accessories 11 January 24th, 2010 10:49 AM



Powered by vBulletin 3.8.7
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
SEO by vBSEO 3.6.1
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright © 2006-2012 MP-Pistol. All rights reserved.
MP-Pistol is a M&P pistol enthusiast forum, but it is in no way affiliated with, nor does it represent Smith & Wesson Holding Corp. of Springfield, MA.