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3.7" Barrel in a P365 AXG Leigon?

This topic can be found at:
https://sigforum.com/eve/forums/a/tpc/f/430601935/m/4520011615

July 07, 2025, 09:36 AM
rotts4u
3.7" Barrel in a P365 AXG Leigon?
I am considering a Sig P365 AXG Legion and I’m considering swapping in a standard 3.7" barrel (non-compensated). I know the AXG Legion is built on the XL/XMacro platform, but I wanted to confirm with the community:

Will a regular 3.7" barrel (like one from a P365XL or aftermarket) fit and function properly in the AXG Legion?
Are there any fitment issues or performance considerations I should be aware of?
Appreciate any insights or experiences you can share!

Thanks in advance.


P226 X5 Lightweight
Sig 226
Sig 1911-22
Sig 516 AR-15



www.ppiparts.com
July 07, 2025, 10:45 AM
delta 2
The barrel will work but you will not have any benefits of compensation. You may want to just get the legion grip module if it’s more cost affective.


For God and Country,

Shannon

July 07, 2025, 01:58 PM
rotts4u
Thanks for the reply !!


P226 X5 Lightweight
Sig 226
Sig 1911-22
Sig 516 AR-15



www.ppiparts.com
July 07, 2025, 02:56 PM
Dorian
Hmmm I was under the impression that the 3.7" barrel will not fit in the Legion slide.
July 07, 2025, 03:18 PM
12131
quote:
Originally posted by Dorian:
Hmmm I was under the impression that the 3.7" barrel will not fit in the Legion slide.

Right impression you’re under. The integrally built compensator is not just a simple extension of the slide. Internal dimensions are different. The 3.7” barrel won’t work in it. This is according to another site.


Q






July 09, 2025, 08:28 PM
rotts4u
So we have one yes and one no. HAs anyone actually tried it and 100% can say it works or not?


P226 X5 Lightweight
Sig 226
Sig 1911-22
Sig 516 AR-15



www.ppiparts.com
July 10, 2025, 11:16 PM
10X-Shooter
I was thinking the legion AXG was a 3.25” comped barrel and slide. I may be wrong. I just installed a Radian Ramjet Afterburner barrel and comp on my 365xl. The proportions look off with a shorter grip but if it performs well I may buy a AXG frame. Probably would have been cheaper to just buy the AXG to begin with…
July 11, 2025, 09:18 AM
c_zielsdorf
I recently picked up a Macro Tacops and bought the Legion grip module from Sig. They went together without any issues.


Disabled combat vet
July 12, 2025, 02:06 AM
12131
quote:
Originally posted by 10X-Shooter:
I was thinking the legion AXG was a 3.25” comped barrel and slide.

The barrel is just the standard original 3.1-inch barrel. The slide (with the integral comp) is XL length.


Q






July 12, 2025, 02:08 AM
12131
quote:
Originally posted by c_zielsdorf:
I recently picked up a Macro Tacops and bought the Legion grip module from Sig. They went together without any issues.

That has nothing to do with the OP’s question.

“Will a regular 3.7" barrel (like one from a P365XL or aftermarket) fit and function properly in the AXG Legion?”

In other words, can you take out the AXG Legion barrel (3.1”) and replace it with the 3.7-inch barrel? Answer is no.


Q






July 12, 2025, 04:06 PM
Lefty Sig
quote:
Originally posted by 12131:
quote:
Originally posted by c_zielsdorf:
I recently picked up a Macro Tacops and bought the Legion grip module from Sig. They went together without any issues.

That has nothing to do with the OP’s question.

“Will a regular 3.7" barrel (like one from a P365XL or aftermarket) fit and function properly in the AXG Legion?”

In other words, can you take out the AXG Legion barrel (3.1”) and replace it with the 3.7-inch barrel? Answer is no.


Is the reason that the extra length of barrel camming up under recoil collides with the inside of the "comp"? I hadn't thought of this before but it makes sense. That means any "slide comped" Sig P365 (maybe P320 as well) cannot have a threaded barrel installed for suppressor use. That sucks. Glad I've been avoiding them. If I want a comp I can get a real one on a threaded barrel.
July 12, 2025, 08:49 PM
12131
There will be no recoil, because it won’t even slide into the slide to fit. The barrel has to slide in at an angle. The 3.1” bbl is no problem, but the 3.7” bbl is too long, so at the sliding angle, it would hit the comp cage and cannot go any farther.


Q






July 12, 2025, 11:28 PM
Lefty Sig
Ok good info.