It’s time to post up a few thoughts on the side charging upper I received as part of the T&E program. Since there are so many different parts involved I will go part by part and hopefully cover everything.

This review is definitely ongoing so these are not final conclusions but rather initial impressions.

What I received is an ambidextrous XSR-15 side charging upper from Crosshill Technology. The barrel is a heavy varmint mystery barrel of an unknown origin. It has no markings on it, not even a twist rate or the type of chamber. The hand guard is a Rainier Arms Sampson Evolution. A Syrac adjustable gas block came installed as did what appears to be a Smith Enterprises Vortex flash hider.

The first thing I had to do when I received the upper was to remove my Seekins bolt catch/release and replace it with the proprietary one that came with the upper. It is important to note that this upper will not function normally with a standard bolt catch--which by default creates a compatibility issue if you plan to swap out standard uppers. Initially this was a major turn off.

Fortunately my lower does not use roll pins so replacing the bolt catch wasn’t that big of a deal. It is by far not an impossible task but it leads me to believe that if you want this particular ambi side charger you will want a dedicated lower for it. It’s just my opinion but a bolt catch/release is not a part that is meant to be repeatedly taken off or put on.




The machine work on the upper itself is quite good. I have a CMT Tactical billet set and the Crosshill fit and finish by comparison is really good. The machine work is great. Zero complaints about any of that except that it is heavy. One other interesting part about the construction is where the charging handle normally is there is a loosely threaded bolt that is flat on one side. If you want to remove the bolt carrier group, take the upper loose as normal, unscrew that bolt and the BCG will come right out (of course you have to also unscrew the charging handles to do this). The bolt is in there only finger tight at best so you can easily take it apart in the field.





The way this upper functions changes some of the most basic functionality of a standard AR15. One of the unique things about the upper receiver is that it not only renders the charging handle obsolete it also renders your standard bolt catch button (mostly) obsolete, and for those who care, it also replaces the forward assist function. All of these factors make it pretty of interesting.

How this upper receiver functions is simple: to charge the rifle just insert full mag, pull it back and let it rip. When your bolt is locked back you no longer have a button (to speak of) on the side of the rifle to release the bolt. A gentle tug on either of the charging handles and away she goes. It can be done in a split second and even with no hands if you want to. (Just bump the charging handle against something with a slight forward motion and it will release) One caveat to this is that if you want to close the bolt with an empty mag in place it quickly becomes a two handed ordeal. You must drop the empty mag, insert a loaded mag, or use two hands…one to pull the charger while pressing the rather small bolt release button. It can be a pain to close the bolt with an empty mag but it’s not a total deal breaker considering how easy the rest of it is to operate. The empty mag/closing the bolt thing seems to be the main quirk I’ve found.





When I first shot the rifle having both sides of the upper open I was expecting a blast of gas in the face. To my surprise there was nothing--however I attribute that to the adjustable gas block. I still want to close off the gas block all the way and see what happens. My suspicion is that I might get a gas blowback but that it wouldn’t be anything unbearable. I for sure would think twice before I started shooting it with a suppressor though. Even the manufacturer does not recommend it.

I have no experience with adjustable gas blocks but it appears this one had already been adjusted. The net result was that the gun seemed to be stroking kind of weird to some degree. It was blowing back far enough to eject brass and pick up another round, but not far enough back to lock the bolt back when the mag was empty. The brass was also being ejected in a different position than normal.



My initial impression is that if I were to own an upper like this I would most definitely have a dedicated lower for it. Using the proprietary bolt catch isn’t such a big deal if you use the rifle as it was intended (and have a lower is dedicated for it). It does take some getting used to as well as learning its quirks. I think this upper would actually be ideal for shooters who may have some sort of impairment such as arthritis, carpel tunnel, or other things that may impair the normal use of an AR15. I am not a cop or a military person so I can’t speak from experience but based on my non professional opinion I would put this upper in the recreational category.

Initially I thought that the ambi charger would be uncomfortable to carry. This concern is largely over blown. However depending on how you carry your rifle and how your sling is set up the charging handle can snag or poke you. If you carry bolt open it could be a problem. It all depends on how you carry and what you are wearing. If you had a plate carrier with forward mags for example I think it could get hung up whether its open or closed.

A couple of quick other notes about the other parts. The hand guard---I love it. I absolutely love the feel of it. It’s very solid.





The barrel is very interesting. I have yet to do any serious accuracy testing with it but my hunch is it has potential for very good accuracy and will handle heavy loads. On the other hand the thing is extremely heavy. I can pretty much guarantee that you won’t be lugging that thing around too much. I guess that type of barrel is mainly used for hunting or gopher shooting or possibly some serious target shooting. Honestly I am still learning the real intent behind having such a beefy barrel. I am not sure what the substantial extra weight is supposed to accomplish. I don't know if I am really going to take a month and try to develop an accuracy load and do extensive accuracy testing in my spare time, but suffice it to say I think as for accuracy the barrel has a lot of potential.

The last part is about the flash hider. Supposedly these are great for what they are designed for but honestly I don’t do much shooting at night and I don’t really care about flash. That aside choosing a dedicated flash hider vs a muzzle brake—I really wonder why that is with this particular set up. I understand the flash hider is suppressor compatible but if you aren't shooting suppressed I might opt for something else.

As for the muzzle device itself---it pings like a tuning fork. You can thump or bump it and it will ping. You can charge the rifle and it will ping. The pinging ringing sound basically gets annoying, but aside from that I don’t really have much of an opinion about it yet.






Now here are some other various shots for you to look at and or ask questions. I encourage you guys to ask questions so that it will give me more to think about. I haven't had much time to really shoot it a whole lot to be honest but I do plan more shooting with it as opportunity presents itself.