Sig Sauer P320 M17 CO2 pellet pistol: Part 2

by Tom Gaylord
Writing as B.B. Pelletier

Sig M17 pellet pistol
Sig Sauer P320 M17 pellet pistol.

Part 1

This report covers:

  • Action
  • Sights
  • Light rail
  • Holsters
  • Disassembly
  • Installing CO2
  • Removing and installing the magazine
  • Manual
  • Works with BBs
  • Summary

Just a reminder that I’m in the hospital today, so I can’t answer questions. Hopefully I will be back home sometime tomorrow.

This is the completion of my description of the new Sig P320 M17 pellet pistol. Now I need to explain something. This pellet pistol is marked M17 — not P320 M17. Sig calls it the P320 M17, so it is correctly identified both here and on the Pyramyd Air website. But I told you that I bought the P320 M17 firearm, and it is marked with both numbers. Let me show you.

Sig M17 pellet pistol markings
On the top left of the slide the pellet pistol is just marked M17. This is also how the Army sidearm is marked.

Sig M17 pellet pistol firearm markings
On the top left of the firearm it says both P320 and M17.

The pellet pistol weighs 2.15 lbs. That will change with the installation of a fresh gas cartridge and 20 lead pellets.


The pellet pistol is double action only while the firearm is single action only. You can pull the trigger repeatedly on the pellet pistol and the striker (which I will soon call a hammer) will cock and fire. The slide does not cock it.

You can only pull the trigger once on the firearm. After that the slide needs to be retracted to cock the striker again. For this reason I think of the pellet pistol as an M17 and not a P320 M17.

One reader wanted to see whether there is a hammer in the pellet pistol, so I disassembled it to show him. Yes, the pellet pistol does have a hammer, even though Sig calls both it and the M17 firearm striker-fired pistols.

Sig M17 hammer
The M17 pellet pistol does have a hammer (arrow).

Sig P320 M17 striker
The P320 M17 firearm does not have a hammer and is a true striker-fired sidearm.


The pellet pistol has fixed sights, front and rear. The front blade has a single white dot and the rear has a white dot on either side of the notch. These resemble the tritium night sites that are on the firearm.

Sig P320m M17 sights
The M17 pellet pistol (left) has white dots on both sights. The P320 M17 firearm has radioactive tritium dots for night sights.

Light rail

At the forward end of the frame is an M1913 (Picatinny) rail for lights, lasers and even dot sight mounts. Given who will be attracted to this pistol, I think this rail will get a lot of use.


Here is one place you will want to take some care. The Army’s M17 pistol is supplied with extended 21-round magazines that may not fit in some civilian holsters. When you buy a holster for your pellet pistol make sure it is compatible with the M17 firearm and not just with a Sig P320 pistol that can be configured in a smaller package.

Sig P320m M17 holster
Make sure the holster you get will fit the M17 with extended magazine.


Disassembling the pellet pistol is similar to the way the firearm is disassembled, but not identical. To disassemble the firearm the slide lock is used to hold the slide open, then the disassembly lever is turned to loose the slide from the frame. On the pellet pistol you don’t lock the slide back. Just pull it back and hold it, then rotate the disassembly lever. It’s quick and easy to disassemble because the slide spring is not strong.

Installing CO2

To install a CO2 cartridge, remove the magazine from the gun. Then the bottom cap of the magazine must be removed. Next, pull down on the magazine backstrap. However, to insert the new cartridge into the mag, put in the large end first. That seems counterintuitive, but it’s the only way it will go in. Then close the backstrap and the gun takes it from there. However, remember to put the bottom cap of the mag back before you insert the mag in the gun because it’s hard to do it afterward. It’s possible but hard.

Removing and installing the magazine

Once a CO2 cartridge has been pierced, the magazine is under pressure and exhausts a little gas each time the magazine is removed from the gun. This may come as a surprise the first few times it happens.

When installing the mag give the bottom a slap to push it up into the gun. That gas needs to be overcome during loading, too. If you don’t, the gun will either not fire or the shot will be very weak.


The manual is well-written, but the print is quite small. I need a magnifying hood to read it. They don’t tell you how to disassemble the pistol, but to remove a jammed pellet the pistol does need to be disassembled and they tell you how to clear the airgun. So it works out.

Works with BBs

Yes, this pistol does work with BBs. I didn’t mention that in Part 1 because it didn’t seem that important, but a lot of people want that capability. So I should have mentioned it. The chambers on the belt in the magazine will grab and hold BBs just as well as pellets, so you decide as you load it what you want to shoot.

The specs say the barrel is rifled but I’m darned if I can see the rifling. Maybe it’s polygonal?


The Sig P320 M17 pellet pistol is extremely realistic. Not only does it look like the firearm, it also operates in very similar ways. And, it’s a pellet pistol. What’s not to like?

19 thoughts on “Sig Sauer P320 M17 CO2 pellet pistol: Part 2”

  1. B.B.
    Wishing you well.
    I pulled the trigger (figuratively) and ordered this pistol on the big weekend sale. It will be my first air pistol with blow back. Being a pellet pistol rather than only bb’s was a major selling point.

  2. B.B.

    Thanks for the clarification between hammers and strikers. During one of the times I had the M17 disassembled, I looked down the barrel at a fluorescent light. I believe I did see rifling.

  3. BB
    I would like to see what kind of velocity you can get with a very light weight pellet if you can. Low powered CO2 pistols that just lob a bb out in an arc are very disappointing. This one is listed 430 fps but it could have been higher.

    But then again most of the higher powered ones seem to have a moving barrel as a striker with a long heavy trigger pull. For example the Daisy Powerline 5170 has a 520 fps listed. Perhaps you just cant have it all.

  4. Wish List Promo,…..

    I see that Pyramid Air is upping their wish list give away this year. I do believe it was 1x 3000 last year. This year is 5x 5000. That is a pretty darn ((substantial)) increase. I had a hard time coming up with 3000 last year.

    At any rate,… perhaps someone with more business experience can explain the idea behind this type of promotion. Me? For one, it will show PA what is of most interest. They can target sales and inventory and orders accordingly. Laser target Christmas sales? A tax write-off? Beyond that?


  5. B.B.

    I continue to pray for excellent post-op care and recovery for you. I think that we may underestimate God when we don’t ask big enough. In the Old Testament God told Israel to “open their mouths wide”, i.e. expect big responses from God. So I’m asking big.

    Minor selfishness here. Waiting for more testing of the Sig ASP20. That may be the one and only for me. I admire the effort (and skill) that members of this blog share almost daily. I intend to own only one, really good, accurate airgun. Perhaps the ASP20? One may hope…


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