I’ve been very happy with the Model1 Sales dedicated .22LR upper. It’s a 20″ bull barrel with national match front and rear sights. Works quite well for Appleseed events and regular plinking. However, I’ve had my eye on Spike’s tactical dedicated uppers for quite sometime. You know. For the “modular” look and feel; 16″ barrel, rail, red dot, fancy furniture, etc. Given the price of another upper, I’ve remained hesitant on buying one. I’ve always wondered if a conversion kit will suffice.
Fortunately I had the opportunity to try one out! Brownells provided a CMMG AR15 .22LR Conversion kit for me to compare the advantages and disadvantages to the dedicated upper. Was either set up more reliable, accurate or easy to maintain? Is it suitable for all applications?
The conversion kit is an easy install. Just remove the bolt carrier group and insert the kit! There have been reports that some modification is necessary for the chamber adapter to fit; however, I did not have any problems with the Noveske N4 Recce standard upper witha 14.5″ 1/7″ twist barrel pinned with a SEI Vortex flash hider.
The Model1 Sales I have has been running smoothly. The only malfunctions I’ve has so far are cartridge related; specifically Winchester Super X .22LR. With over 1000 rounds through this conversion kit, it’s also proved to be very reliable. I have not had a FTF or jam using Federal Champion or Remington Golden Bullets. In fact, I’ve have yet to have any malfunctions related to the conversion. The few isolated malfunctions I’ve had were the result of one Black Dog Machine LLC magazine.
Preliminary results start at 25 yards. The .22 dedicated upper is showing advantages, which is surprising at only 25 yards. I would imagine that the two models would at least show the same performance within a close distance. Variables such as the larger aperture sights on the Noveske could be hindering comparable results. The dedicated upper has national match front and rear sights. To illustrate, I can pass as a rifleman with the dedicated upper using the Appleseed AQT (215-230). I’ve only been getting 170-190 with the conversion kit. Further tests are necessary to determine if I can tighten those groups. It has been reported that other shooters are able to achieve groups as small as 3.5″ at 100 yards.
With regular cleaning at 300 round intervals, it isn’t as bad as I thought it would be. Long periods without; however, there WILL be lead and wax build up in the gas tube. In one instance, I decided to not clean it for awhile. I ended up picking out lead from the gas tube.
My preliminary conclusion is that I would prefer a dedicated upper since I do not have to worry about a gas tube. A gas tube plug is available, if one finds it necessary. Some may find it advantageous if they were training for high power matches or find accuracy mandatory for an AR platform. Our local .22LR tactical matches come to mind. The conversion kit is excellent for those who practice drills engaging targets at 25 yards. Since reliability isn’t an issue so far, it really comes down to application. Maintenance concerns have not become an issue — yet. I would imagine that a majority of the population would benefit from a dedicated upper, especially if they compete. A conversion kit does not appear to have the capability to deliver those small groups. For fun however, the conversion kit is the way to go, especially for the price. It would, in fact, make an excellent Christmas [aka Holiday] gift for your favorite shooter. The CMMG conversion kit with BDM magazine is available at Brownells.
In the future I’m going to try to push it out further and see what the twist rate does to a 40 grain bullet and it’s terminal performance up to 50 yards, maybe even out 100 yards for a more dramatic illustration.
The great thing about the kit is that new shooters appear to enjoy the EBR with the “tactical” furniture more than the regular EBR.

Evil black rifle.
- Assembled kits.
- Chamber adapter and dedicated bolt collar.
- Bolt rails. They’re practically identical.
- Bolt face.
- Notice the firing pins’ difference.
- Right side of the bolts. Almost identical.
- Disassembled kits.
It should work with mine too then. 🙂
cmmg recommends only using 36 grain ammo in their conversion kits.
where can i get just the dedicated bolt collar?
I’m not certain. I imagine if you contact Spike’s Tactical, they could offer one for sale. I believe they manufacture their own kits.
http://www.spikestactical.com/new/z/contact_us.html