Monday, February 29, 2016

MCX CO2 Rifle’s First Shot


How to clear a jam on the SIG MCX air rifle
The white plastic 30 shot belt is inside the SIG's magazine.



As I wrote in the last post, I went to town, got some 90 gram CO2 cylinders and charged the gun. To do this you have to remove the butt unit. It unsnaps with a large button on the right side. The CO2 cylinder screws into the back of the action where the buffer tube would be on a conventional Armalite rifle. The butt tube is a friction fit over the cylinder making the unit feel much more secure, and hinting that there might be more design surprise in store. There was no hiss when the cartridge was pierced hopefully hinting that there are no gas wasting spaces inside the rifle.


Loading  the belt is not hard. once you have played with the magazine for five minutes, the orientation of the belt is not a problem. the pellets are seated form the back and pushed flush with your thumb. Then you use a seating tool to push them in about 1/16 inch deeper. The pellets fit very tightly.


I had found that the magazine went in and out a lot more easily if I cycled the charging handle first. I don’t know if this is the right thing to, but I don’t like to force anything. The magazine is made from the lightest weight plastic on the rifle. So, I cycle the charging handle before inserting or removing the magazine.


I stepped out the back door, released the safety, aimed at a snowbank (more about this later) and fired. I saw the pellet impacted the snow. I heard the SIG made some reloading sounds. These sounds were what I was interested in. I concentrated on the rifle, and started to squeeze off another shot.


The MCX, in the best black rifle tradition, had jammed.


I tried TAP, RACK, BOOM. I pushed up on the base of the magazine, cycled the charging handle, but the trigger would not move. To make things more fun, I could not remove the magazine. The one thing that worked was the safety which I applied. What I hoped would clear the jam, and which I did not have, was a .17 cleaning rod. It was going to be another trip to town.


Pocatello is a small city. We barely have enough people to require the reduction of the freeway’s speed limit. But, town is town. The traffic is much more hectic than our quiet country road. Long story short, I got a .17 cleaning rod.


By the way, I clean my airguns with a pull thru made from string trimmer line.


I gently slid the rod down the barrel until I felt some resistance. A very little more force and the rod went about ¼ inch more. That was all it needed. The magazine slid out and there was a pellet squished back into in the plastic cylinder that was aligned with the barrel.


I reloaded the belt and fired the gun several times, and experienced two more jams. Each jam came after a pellet has been successfully fired. I think that the subsequent reloading cycle did not fully seat the next pellet in the barrel. There is a warning that low gas pressure will not cycle the belt and jam the gun. I am not sure if this is right. The temperature on my back porch was mid 50s. It seemed warm to me after a winter in the teens and single digits. Perhaps the pellets were too tight in the belt or it wasn’t warm enough.




A good cleaning rod is a must have accessory for this rifle.
More to come.

Ron