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Old June 21, 2018, 12:10 AM   #1
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Storm Lake conversion POI shift

Hi folks,

I wanted to ask you a question for anyone with a Storm Lake conversion barrel. I have one in an M&P40c converted to 9mm. I bought it maybe 2-3 years ago and finally got to take it out for a serious spin. It shoots about 1 1/2 inches to the right. My factory 40 cal barrel shoots dead on, point of aim. That bothers me. Occurs with left hand shooting too. I've tried it with WWB, Federal, Remington UMC. These are all practice ammo ~ 115 grain.

Has this happened to any of you? Do you just live with it? If I shot with full size torso targets it would be fine but I shoot these mini torsos with zones and it makes me look bad... to myself

I wish I had tested it sooner so I could have returned it.
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Old June 21, 2018, 12:14 PM   #2
Brian Pfleuger
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Can't say as I've had it happen but why not call and see what they say? Maybe they'll replace it? Maybe not, but it can't hurt to ask.

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Old June 23, 2018, 08:49 AM   #3
Don P
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It shoots about 1 1/2 inches to the right.
I have to ask, are you absolutely sure its not you shooting right???
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Old June 23, 2018, 12:35 PM   #4
Don Fischer
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Now wait a Minute. You rebarreled a hand gun from 40 cal to 9mm and the point of impact changed? Why would that be a problem? Seem's to me you modify a barrel or change it and POI will change. I must be missing something here!
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Old June 23, 2018, 02:38 PM   #5
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That's not unusual, and it's not a lot. I'm mainly surprised you didn't see the POI move down. But chances are the new barrel doesn't lock up in quite the same position. To test this, if you have access to a laser bore sighter and can accurately center it in both barrels, you should be able to pick out a corresponding shift in POI alignment. Then the question is whether it's SL's fault or if it's the original barrel that's a little offset and that had the sights timed to it. If you can, borrow another 40 S&W barrel to try an see if there's a shift.
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Old June 27, 2018, 06:38 PM   #6
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FWIW, I have changed barrels in several semi-auto pistols. Even if the same caliber, I expect POI to change. Just as no two shooters have the same stance, grip, vision, sight picture or trigger press, no two barrels set up in the pistol exactly the same. Here, you even have a different caliber, bullet weight, recoil impulse,etc. There is likely nothing whatsoever wrong with your barrel.......
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Old July 7, 2018, 11:07 PM   #7
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Just an update: so far I have emailed Storm Lake and after waiting several days they wrote me a one liner telling me to fill out their online RMa form. After doing that I’ve waited a few days with no response so I just wrote them an email asking them to check into my RMA request.

I’m pretty sure it’s not me alone that shoots to the right with 9mm but dead on with 40 cal. I was just surprised because I see people say their Lone Wolf or Storm Lake or what have you barrels produce the same POI. Or some will say “no appreciable difference in accuracy” but maybe they were shooting fast. Real fast. I do have a laser trainer that inserts into the barrel. I could try a comparison but it would likely be a 2 person job to compare dot location after triggering it.

Uncle Nick - I am a little disappointed to hear that the sights are adjusted to match the barrels which each have a different POI. I guess part of me wanted each barrel to be a perfect tunnel in relation to the outer diameter. Disappointed but that sounds realistic. I guess I’m not ready to adjust my sights to match a conversion barrel
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Old July 8, 2018, 02:17 AM   #8
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...I see people say their Lone Wolf or Storm Lake or what have you barrels produce the same POI.
Based on what I see at the range, most shooters are unable to determine the actual accuracy, or an accurate point of impact for a handgun.

Before I would have any confidence in a person's credibility to accurately assess the point of impact of a handgun, I would want to see a group of at least 5 shots, measuring less than 20MOA, and shot at 15 yards or more. 20MOA is about 3" at 15 yards, about 5" at 25 yards.
I guess I’m not ready to adjust my sights to match a conversion barrel
When I buy a conversion barrel for a handgun, I also buy adjustable sights to fit the gun and install them.
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Old July 8, 2018, 09:30 AM   #9
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That's sounds normal. My only experiences is with Lone Wolf and Storm Lake. That's why an adjustable rear sight is so important for all of my Glocks.
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Old July 9, 2018, 10:58 AM   #10
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A Lone Wolf barrel in my Glock 20 made no significant difference in POA/POI, or accuracy. I bought it for better chamber support.
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