by Tom Gaylord
Writing as B.B. Pelletier

This report covers:

  • On a dare
  • The adaptor
  • Priming
  • Is it dangerous?
  • Loading the pellet
  • Discharge sound
  • Cost
  • Legality
  • Conclusions

I love it when I’m wrong! I try to be correct in my reporting, but sometimes I hit the wall and splatter all over the place. Today might be the start of one such time. I am reporting on an adaptor I bought to shoot pellets in a .223 Remington centerfire rifle, using the power of number 209 shotgun primers.

On a dare

My late wife, Edith, used to keep me straight by periodically challenging me. Whenever I said something that didn’t sound quite right, she invited me to put my money where my mouth iwa. She learned very quickly that I knew what I was talking about in the field of guns most of the time, but every once in awhile I was off the track. She learned to spot those times and she would call me on them.

She isn’t around to do that anymore, but apparently I got so used to it that I now call myself out! That happened the other day when I was talking about the adaptors that allow pellets to be loaded and shot in firearms. I said many things in my report that would not pass muster in the past, so I decided to dare myself to try pellet adaptors once again. I bought a .223 Remington adaptor to load into my AR-15. We all know that rifle is deadly accurate — putting 10 shots into a little as 3/8-inches at 100 yards. It ought to serve as a good test platform.

The adaptor

Okay, the adaptor is real high-tech (not). It’s a .223 case that’s been drilled out at the base to receive a number 209 shotgun shell primer. An o-ring inside the base holds the primer tight. The neck of the case has been punched on opposite sides to keep the pellet from falling into the case at loading.

The pellet adaptor has two “precision” divots punched into opposite sides of the base of the neck, to prevent pellets from dropping into the larger portion of the case, where they would be difficult to remove.

adaptor base
At the base of the adaptor the primer hole has been drilled out to accept a number 209 shotgun primer. An o-ring inside holds the primer tight. A fired primer is shown next to the adaptor.


The adaptor must be primed with a shotgun primer. The primer is simply put into the hole in the base of the adaptor and pressed in with your thumb. At first I thought it would not go, but eventually I discovered the right amount of force to use and the primer slid home. For as simple as it is, it really works quite well.

adaptor primed
The primer is pressed into the adaptor by thumb pressure. As you can see, there is a lot of primer to go inside.

To remove the primer after it has been fired, a cotton swab through the case mouth works well. Not only does it press out the spent primer, it also wipes carbon deposits from the case mouth.

Is it dangerous?

Is pressing a primer into a case with your thumb dangerous? You know that primers are detonated by impact and pressure. So, is it dangerous? Not really. Your thumb spreads out the force to the entire surface of the primer, where a firing pin strikes deeply in one one tiny spot. Al;so that o-ring makes loading a lot easier.  It does take a little courage at first, but after you have done it a few times it becomes routine.

Loading the pellet

To load the pellet you press it into the case mouth, tail-first. It isn’t easy. It’s like trying to herd a cat! I found that some pellets like Wasps just don’t want to go in. Their skirts are flared out too wide to enter the case mouth. But I was able to load a JSB Exact Jumbo and an Air Arms dome. Neither is easy, but with persistence they do go in. So far those are the only two pellets I’ve tried because I was just trying to become familiar with how the adaptor worked. I will try a range of weights in the velocity test.

adaptor loaded
Sorry it’s a little blurry, but the background is exaggerating things. The JSB Exact Jumbo dome is pressed in as far as it will go. The skirt is sitting on those divots you see in the first picture.

Discharge sound

Here is where I admit I was wrong. The ad copy says this adaptor sounds like a spring-piston air rifle firing. All my past pellet adaptor experience was with handguns that are very loud. I braced myself for the loud bang in my office and was pleasantly surprised by the quiet pop. It was about the same as a RWS Diana 34!

My AR-15 has a 24-inch barrel, so it’s possible that a shorter barrel may make more noise. But as it stands, this adaptor is very quiet. Backyard in the suburbs quiet! Now I am intrigued, for a number 209 shotgun primer has a lot of oomph. This adaptor could allow us to reload our own CB caps. If it is also accurate, then it’s worth consideration.


The adaptor costs $15. Primers cost around 4 cents apiece, so each shot costs that plus the cost of the pellet. It’s more expensive than just shooting a pellet and even more than shooting with CO2, but less than the cost of .22 rimfire ammo. Plus it is as quiet as a rimfire shot through a silencer.


But when you use this adaptor you are still discharging a firearm — not an airgun. If you were hauled into court for shooting this they could charge you with a firearm violation, because the pellet is propelled by means of a chemical explosion. Add to that the fact that you are shooting it in a firearm and it’s clearly not a way to circumvent the law.


I have a lot to test. The ad for the adaptor had a review that said the user was getting groups the size of a nickel at 20 yards. We’ll see about that. I still have a hard time believing this adaptor can be that accurate, given the difference in bore diameters of a .22-caliber pellet rifle and a .22 centerfire.

If it is accurate, though, it will be the first pellet adaptor I have seen that is. We shall see.