At the moment I do not own any semiautos in a centerfire chambering. I'm just about ready to order a pistol can but I'm not quite sure which thread pitch to start with. More than likely I'll end up with both, but between 1/2×28 and M13.5×1 LH which one seems to be more prevalent?

I'm really eyeing up the Navy version of the Walther PPQ, what are the threads on one of those?

1/2x36 on Rock river 9mm uppers FYI.

Glock factory barrels are 13.5x1, most aftermarket (like my LWD) are 1/2-28. My 9mm AR is 1/2-36, but I have a 1/2-36 to 1/2-28 TROS adapter on it. S&W M&P 9 come either 13.5x1 or 1/2-28. Sig are usually 13.5x1. Beretta's are 1/2-28.

Several will tell you the 13.5x1 are less likely to come loose during firing. But, all mine are 1/2-28 so I can't compare. I so like having all my 9mm handguns and rifles the same 1/2-28 so I'm not swapping pistons. Also let's me use them on 22LR and AR57 when I want without changing anything.

Don't do it, it's my biggest pain in the ass host, google the numerous complaints of shooting it suppressed. Btw, it's threaded 1/2x28, but do yourself a favor and get a Sig with a threaded barrel or anything else for that matter. Good luck.

13.5 is most common.

Sig, Glock, HK, ship factory guns with it.

Essentially, most US Manufactures will use 1/2x28RH, except that one time S&W used 13.5x1LH, but they went back to 1/2x28. Most European Manufactures (ie. Glock, HK and Sig) will use 13.5x1LH. In the end, it is up to the manufacture which one to use. But, there are a plethora of aftermarket barrel manufactures which makes it a little bit easier.

I've worked in a gunshop for the greater part of the last 4 years and most of what I see is 1/2x28.

Of my 9mm hosts, Id say that probably 60 percent of them are 1/2-28.   If you have a place like ADCO do threads for you, it will most commonly be 1/2-28.

Sig, HK, glock, Steyr, and several others use 13.5x1 LH. The only 1/2x28 I ever got was a barsto threaded barrel for my Beretta M9A1. I like the left hand threading better on pistols and all rifles have 3 lug. For me 1/2x28 is useless. I have boosters for several different suppressors in 1/2x28 that don't get used.

It depends on your tastes.   If youre into HK's, Sigs, and Glocks -- yeah, youll have 13.5 LH barrels.  Possibly.  





Im a host collector, so let me run down the 1/2 x 28 9mm stuff I have that I can remember off the top of my head.





Glock 17 (LW barrel)


Beretta 92


STI Spartan (ADCO job)


CZ 75c  (ADCO)


CZ SP01 Phantom (ADCO)


CZ 75B (ADCO)


CZ P01 (ADCO)


CZ P07 TB


Walther PPX


Walther PPQ Navy


Sig P226 Tacops (see note below)


Browning BHP (ADCO)


Springfield XD Tactical (EFK barrel)


M&P9


Nagant 7.62 revolver (ADCO)





Maybe a few others, but you get the idea.   Alot of aftermarket barrels come in RH threads, and for good reason.   Also, 1/2-28 boosters allow you to use your takedown pistol cans on 22 hosts.   I do that from time to time.  
For 13.5 LH guns, Ive got a few western European ones.





Sig P226 Tacops (I have a 1/2 28 barrel for a P226 knocking around somewhere, but I dont
use it as the only 226 I have right now has a factory 13.5 LH barrel.)  


Sig P229 Elite


Sig P239


Sig SP2022 TB


G19  (Gen 2, old as shit, has a factory barrel now)


USP 9 SD


VP 9 (RCM barrel, could have gotten it in 1/2 28 though)





Ive got a couple others I cant recall right now, but as you can see, my taste just happens to trend towards guns where the 1/2-28 barrels are more common or readily available.   Its all a preference matter, but neither thread pattern is "useless".    Also, 13.5 LH doesnt resist unthreading in any appreciable, noticable way.   Im not an expert on anything at all, but Ive shot alot of hosts with alot of cans, and they all need to be checked for tightness after every mag.





The same goes for .45.   I prefer .578x28 over 16mm LH threads.   I think I have a HK45CT and a factory G21 barrel in LH thread and thats it.  





I think I would rather have a factory barrel in most cases, but if I cant get one or I intend to shoot it ALOT, i get RH threads.    
 

Thanks for the heads up about the PPQ guys. Went back and looked at the threads, specifically the one on the walther forum and man, what a disaster.

I'd like to buy pistols that come factory threaded, and I prefer European brands over domestic so it looks like I'll start with the 13.5×1 LH for now. I already own a Sparrow and as such have a collection of 1/2 x 28 threaded guns but I'm planning on picking up the fixed mount anyway so no benefit there.

Last thing, one other factory threaded option that I was considering is the CZ P07 Duty but (beyond not seeing any available anywhere) I have no idea what thread pitch CZ uses. Anyone have an answer for that one?

Thanks for all the replies.

The P07 and P09 factory threaded guns are 1/2 -28.