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While fiddling with my W German P226 to try and determine why it doesn’t shoot as well my .40 cal P226’s as far as accuracy, I figured I’d try a barrel swap. The question of whether or not it will function properly comes up occasionally, so I figured I’d give it a try.

The purpose of this exercise was to determine if the 9mm barrel possibly needed to be replaced with a new one, but I wasn’t excited about buying a new one just to see.

I compared the 9mm and .40 barrels and found them to be the same with the exception of the width of the barrel hood extension that fits back against the breech face. The 9mm is .025” narrower than the .40.

When dropping the 9mm barrel into the .40 slide, I figured that there might be some side to side movement of the barrel, but surprisingly, there was not. In fact it actually fit more securely than the .40 barrel that belonged in the slide.

Here’s what I started with, which is the W German 9mm P226 at 15 yards just standing and shooting normally with 124gr traveling about 1100fps.

Those are 1" squares for reference.

I then installed a borrowed 9mm barrel in the W German P226 and got this, which didn’t look too good at all, so I figured my barrel must not be too bad after all.

Last I installed my 9mm barrel, guide rod, and recoil spring in the .40 slide and installed it on the .40 frame. I also used the 9mm magazine, and this is what I got:

Same distance, same ammo, but bit better group, and the POA/POI was almost exactly the same as it is when shooting .40 cal., so no sight change would be needed. The cases extracted and ejected normally and ended up half way across the room, so there was no issue there.

The bottom line is that my barrel is good, sothe old W German P226 still has some issues to sort out...

All in all, it was a pretty successful exercise for a range gun and appears to function OK for just ten rounds, but I plan on exercising it more with a few more range visits this week. It’s also just a sample of…one. But I have a second P226 in .40 that I will try as well.

All of this was just an experiment to see if my barrel was good or bad, and not in any way a recommendation for anyone to rush right out and try it for themselves.

In other words, try it at your own risk!
Posts: 1180 | Registered: October 01, 2013Report This Post
Picture of Nipper
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Thanks for taking up the GaryBF challenge. Like with the P239, some things that aren't supposed to Only one way to find out.

Bought a Sig OEM 9 mm barrel for my P239 .40. Everything that wasn't supposed to work did. So far the gun has been 100% reliable.

1) Native Sig OEM 9 mm barrel in .40. No conversion barrel.

2) 9 mm mags in .40 pistol. They are narrower than the .40 mags and properly fit the native P239 9 mm frame (narrower mag well). Rattle a little, but work.

3) Able to use the native .40 mags with 9 mm ammo. Function fine.

4) Installed the Sig "Plus 1" base plates on the 9 mm mags. Sig lists them for .40 mags only...not the 9 mm.

This kind of stuff is fun, as long as there are no safety issues involved. Keep us posted.

An expert is one who knows more and more about less and less until he knows absolutely everything about nothing. --Nicholas Murray Butler
Posts: 3663 | Location: Northeast | Registered: June 29, 2006Report This Post
That's just the
Flomax talking
Picture of GaryBF
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Well done.
Posts: 10625 | Location: St. Louis, Missouri | Registered: February 04, 2008Report This Post
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