by Tom Gaylord
Writing as B.B. Pelletier

Crosman DPMS SBR
Crosman’s DPMS SBR full auto BB gun.

This report covers:

  • What is it?
  • Watch the video
  • The gun
  • Blowback
  • Controls
  • Disassembly
  • Stock
  • Forearm
  • Loading
  • Shot count
  • Bolt holdopen
  • Sights
  • Summary

Today we begin looking at the Crosman DPMS SBR full-auto BB gun. First — the acronyms. DPMS = Defense Procurement Manufacturing Services. WHAT??? It’s a shop that was initially in Osseo, Minnesota and opened in 1985. It started manufacturing parts for military weapons like the M16. It’s now part of a larger conglomerate that’s located in Huntsville, Alabama. SBR = Short Barrel Rifle. Another name for a carbine, and, in this case, the rifle that was shortened was already a carbine.

What is it?

The DPMS SBR is Crosman’s select-fire BB gun that shoots 25 BBs per magazine. Select fire means both full and semiautomatic fire are available via the conventional M16 selector switch. Gun bashers will tell you that AR-15s are automatic, but in fact that is incorrect. Civilians in the U.S. may not purchase full auto firearms without a lengthy process that vets the owner, tying the gun to him by serial number, and costs $200 per firearm so registered. AR-15s are semiautomatic, only, so a selector switch applies to the full auto military platform, only.

Watch the video

I’m going to recommend that any of you who are interested in this gun watch Tyler Patner’s video review. You have to scroll down the page and click on the video that’s on the right side. It’s concise and addresses all the questions you might have. I watched it because, frankly, I cannot read the owner’s manual. The manual is printed in 1-point type that I cannot read even with bifocals and a magnifying glass. But the video addresses everything you need to operate this gun. Watch it.

The gun

The DPMS weighs 6.5 lbs. which is heavy, but feels good. The frame is made of glass-filled polymer that feels similar to the synthetic receivers found on many AR-15s these days. You wouldn’t want it to be made of aluminum because it would be too heavy and would cancel a lot of the blowback impulses.


Yes, the DPMS is full blowback, so you feel the pulse of every shot. The bolt cycles back and forth just like a firearm bolt. At the NRA Show several months ago I watched as dozens of people stood in line to shoot it at the airgun range. I know the Pyramyd Air employees who ran that range spent a lot of their time reloading the DPMS, because everybody wanted to shoot it.


All the AR controls operate exactly like they do on an M16, with the single exception of the forward assist (the button on the right side of the receiver that pushes the bolt forward so the extractor can grab the rim of a cartridge). Since a BB gun doesn’t use cartridges there is no need for a forward assist.

Crosman DPMS SBR forward assist
Forward assist (arrow). The 6-position buttstock is fully forward in this photo.


The DPMS disassembles very similarly to an AR-15/M16/M4. Two pins connect the upper receiver to the lower receiver and when they are out the receiver halves come apart. Then the parts of the bolt can be either removed or pushed back out of the way to clear jams in the barrel. You rod through the muzzle and the BB(s) fall out of the breech. There is no other reason to disassemble the gun, though I know many owners will want to, for old time’s sake.


The buttstock is adjustable to 6 positions. The length of pull runs from 11-inches to 15-inches, so you are bound to find a setting you prefer. A spring-loaded button under the butt unlocks the stock for adjustment.

Crosman DPMS SBR stock
The 6-position buttstock is extended all the way.


The forearm has 1911 Picatinny rails on all 4 sides. You can mount optical sights, flashlights, lasers, bipods, coffee grinders and other grips if you like. Think of this gun as a motorcycle that’s ready to be accessorized!


Now we come to the interesting part — the magazine. I told you that all the controls work like an M16. But not the magazine. It doesn’t drop free. Push the release and pull on the mag to get it out.

Once out, move to the bottom of the mag and pull off the side cover. The directions are written on the magazine floorplate.

The mag takes two 12-gram CO2 cartridges. And, the order you install them is important. The left cartridge goes in first. If you try to install the right cartridge before the left one, all its gas will leak out. The Allen wrench you need for piercing the cartridges is inside the mag. Crosman also includes a BB speedloader with the gun that I will show you in Part 2.

Crosman DPMS SBR CO2
Install the left CO2 cartridge first. The Allen wrench is stored inside the magazine.

Shot count

I know you are concerned about the shot count when two CO2 cartridges are involved. Pyramyd Air saw 125 to 150 good shots on either semi- or full-automatic fire in their testing, so it’s okay. I will test it for you as well.

Yes you will go through a lot of cartridges but I’m guessing most of you will use this primarily as a party gun. So, at every holiday and gathering plan on burning through a pile of cartridges and BBs. Buy ‘em in bulk.

Bolt holdopen

After the last BB has been fired the gun stops shooting because the bolt is held open. This is a marvelous way to save gas!


Now we come to the fun part. The DPMS has back-up iron sights — BUIS. That’s where we are in 2018 — iron or non-optical sights are considered for backup use, only. The front sight does not adjust and the rear adjusts for windage, only. The rear sight has two leaves — one with a fine peephole and the other with a large battlesight hole. I plan to shoot with these sights.

Of course the Picatinny rail on top of the gun means you can install a real pair of BUIS that do adjust, if you prefer. Or you can install an optical sight, which I plan on doing. The sight I will install is one that Pyramyd Air does not stock at this time. I hope to change that if it tests out. It’s that wee teeny holographic sight I showed you from the SHOT Show.

Crosman DPMS SBR UTG dot sight
The UTG Reflex Micro-Dot sight is small and capable — I hope. We shall see.


This DPMS is a hot one. It’s not unlike the MP40 I tested for you (and subsequently purchased) last year. It’s full-auto and it really works. For those who want full-auto, this is one of the very few games in town.