Gun Matchup: Glock 21 vs. Sig Sauer's P320 (What Should You Choose?)

May 28, 2019 Topic: Security Blog Brand: The Buzz Tags: GunsPistolsSig Sauer P320Glock 21Sig SauerGlock

Gun Matchup: Glock 21 vs. Sig Sauer's P320 (What Should You Choose?)

You might be shocked at the answer. 

For the benefit of people living in any of the free states, the full size SIG P320 in .45 ACP uses a 10-round mag while the compact version uses a 9-round mag.

On the other hand, the Glock 21 uses a 13-round mag. That’s a whopping 30% more .45 ACP firepower compared to its full size P320 counterpart, and 33.33% more compared to the compact P320 version.


As of this article’s writing, the full size SIG P320 costs $597 on SIG’s website. It comes in a carrying case installed with the regular 3-dot contrast sights, two 10-round mags, and a holster. Upgrading the factory sights to SIGLITE (SIG’s brand name for their 3-dot night sights) will cost an additional $82.00, bringing the total to $679.

The compact grip module for converting the SIG P320 to a smaller CCW piece costs only $44. Adding that to the $679 price tag on the SIGLITE package, the total will be $723 — the cost of the entire package.

On the other hand, the Glock 21 Gen4 comes in a carrying case with four different backstraps (two of which are beavertail-type grips), three 13-round mags and an ammo loader. It retails for $599 on Glock’s website.


I’m giving points to the SIG P320 for the following:

  • Concealed carrying is easier because the grip length can be changed by installing the FCU in a compact grip module.

  • Factory 3-dot contrast sights are easier to aim with and more dependable being made of metal, much better than Glock’s stock plastic sights everyone hates.

  • Compliance with more non-free state laws and the fact that it is now the US military’s standard issue firearm mean there will be zero availability issues.

  • Better Ergonomics with contours and palm swells on the grip and front slide serrations so it will be easier on the hands.

  • PVD finishing process is reported to be slightly better than Melonite (70 HRC vs. 64 HRC). And Gen4 Glocks are reported to have more spot rusting compared to other generation Glocks.

  • Aesthetically pleasing especially when compared to Glocks (I’ve always hated how Glocks look).

  • The base model without the upgraded sights and aftermarket grip module is $20 cheaper than a stock Gen4 Glock 21.

And the Glock 21 Gen4 gets points for the following:

  • Can be converted to a ton of different calibers, making it the more adaptable platform for more use case scenarios.

  • Relatively the safer option, as no Glock pistol I know has ever had problems with drop tests (unlike that little fiasco about SIG P320s going off when dropped at a negative 30° angle).

  • Holds 13 rounds in the mag, which is much better compared to the SIG P320’s that can only hold 10.

  • Lower bore axis makes it easier to shoot fast and accurate follow-up shots.

  • Bullets come out of the barrel faster because of the polygonal rifling design.

  • No issues with manual controls (unlike SIG P320 owners complaining about how far back to the rear its slide catch lever is).

  • For $599 you get three 13-round mags, so you get literally more bang for your buck (don’t even get me started with SIG owners complaining about how expensive those Caliber X-change kits are).


This has been a real tough comparison. Both handgun platforms have their fair share of pros and cons.

Either one excels where the other one fails, to the point it’s making me think, did SIG Sauer and Glock conspire so that handgun enthusiasts like you and me would never be satisfied with either and end up buying both?

Nah I think it’s just my overactive imagination. But I digress.

If you’re in the market for a full size .45 ACP pistol, both the SIG P320 and Glock 21 will be great options, but do take note of that bulleted list that summarizes everything on top. It’ll also make sense to go to a range where you can rent these pistols, then shoot both and see which one you handle better.

So, for Round 8 of our series of Handgun Showdowns, it is with much frustration that I’m shaking my head right now as I have to declare this match a draw.

This article by Mike Ramientas originally appeared at Gun News Daily in 2019.