Launcher Reviews

GROG'S M-203 Review and photos


Et-Cetera 37mm launcher

This review in on the Et-cetera launcher. The launcher is sold by a number of companies, such as Bushmaster and Cobray. The launcher is all aluminum construction, and varies in price depending on model. Usually between 150 and 250 for the long slide models. I have owned two et-cetera launchers, and found that they are adequate for the price paid. (If you want M-203 quality, then buy an M-203!)

The et-cetera barrel is a true 37mm. It is very thick aluminum, and made tough. It takes a lot to damage these barrels. I have only known of one that ever failed, and the explosion that caused it was powerful enough to bend an AR heavy barrel. The launcher is easy to clean, and mount. I do however recommend a little gunsmithing on the mounts to tighten them up to the bottom of the AR. It mounts to any length AR and has a number of positions for the mounts to engage the barrels. If you desire to modify the mounts, the basic reloading disc offers photos of how to do them easily. I also modified the firing pin, and sharpened it a bit, to make it more of a pin and not rounded as it comes from the factory. I also modified the butt plate, as it did not hold the larger rimmed casings. I used a lathe to ream it out a bit. Simple things that any gunsmith could do for you if you can't do it yourself.

Here's a photo of one of my et-ceteras:

high mount 37mm

Notice how close to the AR it looks! Also the handguard, and how snug it is! It is a nice functioning launcher, and is easy to clean. I recommend it for a first time launcher purchase. 


RPB 37mm launcher


The second launcher is an RPB launcher. This launcher has a steel barrel and rail. It is very important to keep this launcher clean. Once fired with black powder rounds, it will rust and corrode very quickly unless cleaned and oiled well. It is possible to bend the rail on this launcher, so care needs to be taken when mounting not to do that. If the rail is bent, it will make closing and opening the launcher difficult. Also, don't let the steel barrel fool you. A steel barrel will blow apart just as quickly as an aluminum one! Ask any metallurgist, and they will tell you that there are types of steel that is WEAKER than aluminum alloys. If you are firing things out of your launcher that would do this, you shouldn't have a launcher period. Keep in mind these are signaling pyrotechnic launchers. If used in any other manner, you risk hurting yourself, others, and being arrested.

The RPB I owned was a good launcher, however there were a few things I did not like about it. First off, the pins that hold the internals in place had a tendency to back out and mess up the trigger. The et-cetera has screws that hold all the parts in very well. Also, the steel barrel was too heavy for my little light CAR. The addition of the RPB added quite a bit of weight to the front end. Also, the launcher tended to rust up quickly if not sprayed down with CLP and greased. The locking latch was difficult to press, and it gouged into the launcher barrel rail. No matter how much I oiled and greased it, it still dug in. The RPB goes for around 225-250. I say, not worth the extra bucks for a launcher that rusts so easily. It looks nice on a long AR, but not on a shortie. If the fact that it has a steel barrel makes you feel better, then by all means, knock yourself out. Like I said, your trust might be misplaced. They make fragmentation grenades with steel too.


"Thumper" Review




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Copyright 2002 Grog's 37mm and40mm Information
Last modified: 05 NOV 2018