[wingman1800]

will a 9mm barrel work on a .40 cal slide? will the gap at front between barrel and slide be bigger than a 9mm barrel in a 9mm slide?
thanks
Tom

 

[stlmia]

Yes and yes. For the latter question, the difference wont be huge.

Pics below with my P250s.

.40 slide/.40 barrel and 9 slide/9 barrel

.40 slide/9 barrel

 

[wingman1800]

perfect !!! thanks
tom

 

[Cheap Shot]

The muzzle end isn't the only place that a 9mm barrel won't fit a .40 slide. Those parts weren't made to work together and this seems like a potentially dangerous thing to do.

 

[hardluk1]

Between having a different extractor and skinner barrel don't bet your life in it working reliably .

 

[stlmia]

OP didn't ask for an opinion so I didn't feel compelled to give it.

But for the record, I agree with the two posts above. I have never run it this way, and don't think I ever will. However, you will find several forum members that run it this way without a problem.

Have to decide for yourself whether the trade-off is worthwhile.

 

[wingman1800]

Thank you.............

 

[gundrted]

I run a 9mm threaded barrel in a 40 compact slide with no issues.

Here is some science to help you make your decision. The difference in the outside diameter of the 9mm barrel is -.5mm from a 40sw barrel.

http://sigtalk.com/p250-p320-modular-pistols/177330-p320-barrel-measurements.html

One of the most asked questions on this part of the Sig forum seems to be around barrel swaps. There is a very nice thread showing the C slide on a SC frame and vise-versa.

People have very different opinions about swapping barrels vs using a x-change kit. Comments vary from Sr. Mix-a-lot to bring out your dead. Just to be transparent, I'm in the Sr. Mix-a-lot camp.

I got out my digital calipers and took some measurements.

My digital calipers is a Milutoyo Model CD-6" set to mm and zeroed with jaws together.

My measurements in mm include:

1. OD near breech
2. OD near muzzle
3. width across breech

Below are my findings.

• Sub-Compact 40sw: 1-14.45, 2-14.49, 3-16.63
• Sub-Compact 9mm: 1-13.95, 2-13.98, 3-16.65
• Compact 40sw: 1-14.45, 2-14.49, 3-16.65
• Compact 357sig: 1-14.47, 2-14.49, 3-16.67
• Compact 9mm Threaded: 1-13.95, 2-13.99, 3-16.64

I am making no statements of what this data means or doesn't mean. I'm simply providing the data for others to draw their conclusions about how to use the investment they have made or are about to make.

Attached are some pics to go along with the above data.