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AR15.COM
3/11/2026 6:30:09 PM EDT
[Last Edit: rebel_rifle][Edited]
I have a fairly early (late 90’s) P 229 I am thinking of converting to 9 MM. other than barrel, recoil spring and magazine swap, what else would be required? Extractor possibly?

Anyone done this?

Update: After reading all of your posts and doing some online investigation, I ended up getting an Sig .357 barrel. Mags are the same, extractor , recoil spring, etc. I saw no need to spend the bucks that would have been necessary to buy a complete 9MM slide.

Took it to the range today and it shot perfectly. Since the .357 Sig is known as being “snappy” I was prepared for it to be that. With the size and weight of the 229, it was not really noticeable.

The only issue is that it shoots low which I had been told it would be. Found the right height front sight on eBay and will install that when it gets here.
3/11/2026 6:38:02 PM EDT
[#1]
that is an easy swap

A 9mm specific conversion barrel is needed as well as a magazine as you stated

EFK and Barsto have them, but they are much pricier than I remember

I guess a lot of manufacturers exited to making other products

I haven’t changed the  extractor or recoil spring
Where is my black turtleneck? I can’t do spy shit without my black turtleneck.

Tennessee Squire
3/11/2026 6:46:12 PM EDT
[Last Edit: NonTypical361][Edited] [#2]
The extractor is the same, but a conversion barrel is needed.
I would just buy a complete 9mm slide for the P229 instead.
3/11/2026 6:59:25 PM EDT
[#3]
Conversion barrel and mags are all you need. I’ve done this more than once with 229 and 226.
3/11/2026 7:40:00 PM EDT
[#4]
Matrix Precision has new complete 9mm slides (minus barrel, recoil spring and sights).

You can sometimes find complete slides on Ebay, usual caveats apply.

I think - but am not sure - you'll want to use the E-2 (or is it E-1) magazines, which fit the non-9mm P229 early frames as well as current production P229s.

Thing is, though, by the time you buy a slide etc, it might come out about even with buying a used 9mm P229.
3/11/2026 8:30:04 PM EDT
[#5]
Good deal on a 9mm Legion slide in the EE.
https://www.ar15.com/exchange/topicEE.html?t=2567801&f=89&type=1
3/12/2026 12:42:28 AM EDT
[#6]
Quote History
Originally Posted By NonTypical361:
Good deal on a 9mm Legion slide in the EE.
https://www.ar15.com/exchange/topicEE.html?t=2567801&f=89&type=1
View Quote

Looks like no barrel, no recoil spring and guide rod.
3/12/2026 5:20:32 AM EDT
[Last Edit: NonTypical361][Edited] [#7]
That is correct. I would rather have the correct recoil spring anyway. Just putting it out there since it had X-ray sights and it was a legion model. It would still be cheaper than a Matrix slide without sights.
I have spare slides for all of my Sigs. It makes life much easier than disassembling slides when I’m at the range.
3/12/2026 9:32:55 AM EDT
[#8]
Quote History
Originally Posted By jwliv180:
Matrix Precision has new complete 9mm slides (minus barrel, recoil spring and sights).

You can sometimes find complete slides on Ebay, usual caveats apply.

I think - but am not sure - you'll want to use the E-2 (or is it E-1) magazines, which fit the non-9mm P229 early frames as well as current production P229s.

Thing is, though, by the time you buy a slide etc, it might come out about even with buying a used 9mm P229.
View Quote


After looking at the costs, I agree with what you’re saying. I have several other 9 MM’s that I can shoot. I’m just going to leave this one as is.
3/12/2026 10:38:34 AM EDT
[#9]
Or build a Matrix 9mm 229...
Where is my black turtleneck? I can’t do spy shit without my black turtleneck.

Tennessee Squire
3/12/2026 10:51:10 AM EDT
[#10]
Just for the record, the 229 requires a conversion barrel to go from 40 to 9


The 226, by contrast, allows swapping 40 and 9 barrels without any “conversion” paraphernalia other than a magazine for the appropriate caliber.

I know OP asked specifically about the 229.
But this question and comparison is frequent.
---------------
They who can give up essential liberty to obtain a little temporary safety, deserve neither liberty nor safety. - Benjamin Franklin, 1775
3/12/2026 3:23:49 PM EDT
[#11]
I'm not sure how the .40 breech face (slide) would negatively affect the overall reliability or performance.

It would probably work, but it might not.  I would rather get an actual 229 9mm slide for that conversion.
"I guess you already know that there are angels masquerading as people walking around this planet and your mom was the bravest one of those." - Idgie Threadgoode, Fried Green Tomatoes
3/12/2026 8:30:12 PM EDT
[#12]
All you need is conversion barrel. The 40 mags will work just fine, but the rounds will rattle.
3/12/2026 8:50:46 PM EDT
[#13]
I did a Barsto conversion barrel and it ran fine out of my 40 mags. I didn't keep it long though because there was a big POI shift to the point where my sights weren't usable. If I were to do it again I'd just do a slide. That way you can tweak it and leave it.
BikerNut:
Normal people like motorcycles. Real people like motorcycles.

People who don't like motorcycles are just... weird.

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