by B.B. Pelletier

Part 1
Part 2
Part 3

The SIG Sauer P226 X-5 Open combo BB pistol comes as an adjustable-sight version for just a few dollars more than the same gun with fixed sights.

This is an extended report to cover the use of 4.4mm lead balls in the SIG Sauer P225 X5 Open combo pistol. I don’t know if you caught it, but while writing Part 3 we discovered that this pistol is also called the Open model here in the U.S., as it is elsewhere in the world. That has been corrected on the website and we will now refer to this model as the Open combo. It’s also called the X-FIVE and not X-5 or X5. However, that would involve correcting a whole bunch of links, and we’ve opted to not make those changes at this time.

I mentioned in the comments on Part 3 that I’d forgotten to test the pistol with 4.4mm lead balls, as I’d promised, so today’s report will cover that. However, while researching the material for today, I discovered some other related things that you may be interested in.

Why 4.4mm and why lead?
The reader who asked for this report shoots in his garage and wants to reduce the BB bounceback problem. Lead balls will certainly do that, but not all BB pistols are able to shoot lead. Some guns rely on the magnetic properties of the steel BB to hold it in place during the firing sequence, but this pistol isn’t one of them. It looked like it would handle lead shot just fine.

Another time we use a lead ball instead of a steel BB is when the barrel is rifled. The Russians did that with their Makarov BB pistol; and after I saw the rifling, I tested it with lead. EAA, the importer of the gun at the time (Pyramyd Air now imports all IZH-Baikal airguns directly from the manufacturer), was very adamant about not using lead balls when I reported it back in the late ’90s. They went to great lengths to disparage what I said about using lead balls in IZH BB guns with rifled barrels, claiming that the manufacturer expressly instructed them to advise using steel BBs exclusively. When I went to IWA (the European SHOT Show) in 2006 and spoke directly to the IZH engineers, they acknowledged that their rifled bores did work best with lead, even though they also worked well with steel.

Size matters, too
Another thing that enters into this discussion is the diameter of the ball. A steel BB these days measures around 0.171″ to 0.173″ in diameter. The Daisy zinc-plated BBs I used to test this pistol for accuracy in Part 3 measure 0.172″. They’re very uniform, which contrasts sharply with BBs of the past.

Lead balls that are 4.4mm should measure 0.173″ in diameter, so they would be one-thousandth larger than the Daisy BBs I just mentioned. And this, my friends, is why it helps to understand a little of the firearms world; because in a firearm that uses lead bullets, you usually want the ball or bullet to be at least the diameter of the grooves or one-thousandth of an inch larger. There are exceptions to that rule, of course, but I’m not going there today.

Putting it simply, a 4.4mm (0.173″) lead ball should fit the bore of a given gun better than a BB that measures 0.172 inches. If the bore of the gun is very tight, the larger ball can cause problems since CO2 guns do not have the same level of propulsive force as firearms. There are limits to what they’ll shoot.

I know that most BB guns are smoothbores. This one certainly is. And I also know that the bores of these guns are slightly oversized to cut down on jams. You could live a lifetime and never see a BB get stuck in the bore of a BB gun if you live in the U.S. and use Daisy, RWS or Crosman BBs; but there are other places in the world where the tolerances of BBs are not held as tight, and you get them both oversized and undersized. Manufacturers allow for this by making their smoothbore barrels just a trifle larger on the inside.

In a nutshell, those are the considerations I took into account when deciding to test this pistol with 4.4mm lead balls.

Not all balls are the same
Sometimes I get surprised in the strangest ways. I already had a lifetime supply of 4.4mm lead balls that I purchased back when the Haenel 310 trainers were coming into this country in the mid-1990s. I wanted to make sure at that time that I wouldn’t be cut off, so I went a little overboard and bought a case of ammunition. Let’s call that 50,000 balls.

A few years ago, while walking the aisles of an airgun show, I saw some tubes of generic 4.4mm lead balls for sale. I picked up a couple tubes for various reasons, including today’s test. Little did I know until this very day, though, that those balls are not 4.4mm, but rather 4.25mm and rather slipshod at that!

Who cares? Well, 4.25mm to 4.3mm (if that is what they really are) measures 0.167″-0.169″ in diameter. Not only are these lead balls undersized, based on what I was told when I bought them, they’re also quite variable, which is the kiss of death if you want to hit anything.

The 4.4mm lead balls I bought at an airgun show (top) are actually a lot smaller than advertised. They’re really 4.25-4.3mm. Bottom picture is a copper-plated 4.4mm ball from the Czech Republic — Β and it’s right on the money.

The test
The test was 10 shots from 25 feet with a strong-side barricade hold. I’m grabbing the door jamb and using my left arm to support and steady my shooting hand. It’s the most accurate hold I can use for this test.

The eyes have it
One more variable was my eyes. Just the day before I tested this pistol I was at the rifle range with Mac and another friend trying out some different guns. Mac had just cleaned my clock by shooting a half-inch five-shot group of .17 HM2 from a single shot target rifle at 50 yards. I shot the same rounds from the same rifle into just over an inch.

My other friend suggested I put on my bifocals so I could see the front sight of the O3-A3 Springfield battle rifle I was about to shoot. I did and proceeded to shoot five .30-06 rounds into a group measuring 0.49 inches. I used the regular combat sights that came with the rifle and shot factory 150-grain Federal ammunition. This is the best open-sight group I have shot at 50 yards in many years, and it cemented in my mind the need to wear my glasses whenever I shoot with open sights.

The smaller group of five rounds (excluding the separate shot above the group) was fired from an 03A3 Springfield rifle at 50 yards with issue sights while wearing my glasses. The lone hole was the first shot, taken with the rifle’s front sight protector still on the sight. It hid the target so I had to guess where it was. The six holes in the bull were shot with peep sights on a .17 HM2, but I wasn’t wearing glasses.

For today’s pistol test, I shot the first 10 shots wearing my glasses. The results were not any better than what you saw in Part 3 with steel BBs.

Shooting the P226 X5 with glasses made the front sight fuzzy. The 25-foot group wasn’t a good one.

After seeing the group shot with glasses, I knew something was wrong. The front sight simply was not clear at arm’s length. I took off the specs and just used plain safety glasses for the next group. The results speak for themselves.

Without glasses, the front sight sharpened considerably, tightening the group. However, regular steel BBs made even better groups in this pistol.

This SIG Sauer BB pistol continues to delight me. This time, I learned a very important thing — don’t trust that something is what it is represented to be. If it’s ammunition, measure it.

This pistol offers the most realistic training of any air or BB pistol I’ve tested. While there’s always some training value for firearms with any airgun, with this one there’s quite a lot. This is an airgun I would recommend to my friends.