Launcher Review T&E



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The Slam-Fire

Made by MLR Distributing LLC


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This review is going to be on the 37mm Slam Fire Launcher, made by MLR Distributing, LLC. Mark Rogers is the owner of the company, and provided me with a sample launcher, his model with the trigger and stock, for testing and evaluation. The basic launcher comes in a hard shell case. The launcher with the attached stock will be available with an Uncle Mikes submachine gun case for an additional charge. The launcher itself is a three part system, including the fore-grip and barrel group, the rear grip and receiver/trigger/firing pin group and the stock. The launcher is available for purchase in three configurations:

1.  37mm launcher without trigger or stock-- $85.00

2.  37mm Trigger Launcher-- $110.00

3.  37mm Trigger Launcher with stock-- $150.00  Prices are current as of 01 Apr 09

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As you can see, the launcher is priced to sell! When compared to other 37mm launchers on the market, which sell for hundreds to over a grand… In a day when it seems that every distributor is trying to gouge people, it is good to see that there is at least one that will continue to offer a quality unit for a very reasonable price.

The trigger system in this slam fire launcher serves as a safety, so the launcher will not close fully until the trigger is depressed, which can be a good thing if you need to keep a round in it. The weight of the barrel alone could set off a primer, so the trigger is a good investment.

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Upon inspection, the launcher is made of steel, all parts except the pistol grips and rear of the stock. The stock is a standard, commercial version of the AR-15 collapsible stock commonly available. The buffer tube from the stock screws into the rear of the launcher unit. The launchers without trigger or stock do not have a rear piece for the stock to screw into. If you want a stock attached, purchase the one with the stock. The finish of the launcher is excellent, a dark black Parkerizing that is flawless. It matches the AR stock very well. If you wanted, you could substitute a standard AR stock, by simply replacing the carbine buffer tube with a standard one and stock. This might make the launching platform more stable, if you desire more accuracy. The outside surface of the barrel (the part that slides into the receiver group) must have a light coat of oil, as these two pieces fit together very well. I’m sure with use, the parts will loosen up a bit. In a slam fire type launcher, a tight fit is a good thing, and will keep any escaping gasses from the launch contained. The fit and finish of this launcher is excellent. The barrel is made of thick steel, and has been tested by the company to 30,000 psi. This is 5,000 psi over the pressure generated by the 40mm high pressure chamber in LV munitions. The launcher is substantial, but not too heavy for its size. The pistol grips are standard AR-15 type grips, and are mounted to two welded steel blocks to the barrel and receiver group. There is no movement in the grips, and they are well attached. When the two sections (barrel and receiver) are together, there is no play between them. Upon inspection of the interior of the barrel, I see no indication of welds going through, or any other defects. This is truly a quality launcher.

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The operating instructions of the unit are very simple to follow. To load the unit, you pull out on the forward handgrip, removing the barrel assembly from the launcher. Place your munition into the barrel and replace the barrel into the receiver. To fire the unit, simply depress the trigger (sear) which will allow you to ‘slam’ the barrel into the receiver fully, where upon the fixed firing pin will strike the primer, firing the launcher. To unload the spent casing, simply open the launcher and allow the casing to fall out. (You may need to depress the trigger to accomplish this action.) The way in which this launcher functions would negate any difficulties one might have in using different types of 37mm munitions. We all know the rim thicknesses of 37mm vary quite substantially between manufacturers. Def Tec uses both a thick rim for their barricade penetrating munitions, and a thin rim for their other types, ALS uses a step rim, as well as Federal. The way the slam-fire functions, it will take any of those rims, and fire the rounds without a problem.

The launcher was test fired as it was received. The only thing I had to do was screw the stock into the rear of the unit. The rounds I used to test and evaluate this launcher were provided from my personal collection. I have video recorded the testing portion of this evaluation, and the test movie is linked below. As this launcher is not registered as a destructive device, no anti-personnel munitions will be tested at this time. This launcher could very well be registered and those munitions used, as this is a very well made launcher. It would be easy to add a serial number and form 1 it, or any of the other versions. MLR has plans to engrave each launcher, with their information and a serial number to aid in this.

As I was going to test fire at least one pyrotechnic round, I waited until the surrounding area was well wet with a previous days rain. A must when firing any pyrotechnic burning type rounds. Forest fires are not your friends, especially when you cause them. Here are my thoughts:


 The launcher functioned well, and is simple to use, as expected. I used two of the CS 37mm barricade penetrators commercially manufactured I had on hand from my personal collection. Both functioned as expected. Also, as I expected, it was hard to use the launcher accurately and get a point of aim, without any sort of sight on the tube, even from only 25 yards. This deficiency is being addressed, and a version of the slam fire will be offered with a section of rail, to mount optics, or laser, or standard AR type sights. The target I set up is about standard window size, piece of treated lumber plywood, 2’ x 4’, with a 4x4 post across the top and bottom, with white Tyvek covering the target board. I took position approx 25 yards away, and loaded and fired the first round. Aiming as best I could, the round impacted the top 4x4 to the right of the target board about 6”. The second round was loaded and fired, and missed the target board, but not by much. I then loaded and fired a 26.5mm green star flare. The round functioned properly, however, I recommended some sort of system to hold the 26.5mm inside the adapter, as it could fall out prior to launch. This problem is also being addressed by MLR, and I was told the new adapter will contain some system to correct this deficiency.


After firing, I used the included bore brush, and hot soapy water to clean the launcher, as the Def Tec CS and 26.5mm were both black powder munitions. The brush worked very well for this purpose, and I recommend it for those that need a good, easy to use bore brush.


The launcher has very good fit and finish. The price cannot be beat, and the quality of the workmanship and materials is excellent. I made the following minor recommendations to the manufacturer:

1.  As the launcher is 37mm, and is obviously capable of handling any of the LE type munitions on the market today, a sighting system is a must. This launcher is a fantastic invention that does not need any improvements as it stands to make it a good launcher for most 37mm applications. If some small improvements are made, it will appeal to a much larger audience. This could be accomplished by simply adding a weaver style scope mount block or rail system to either the sliding front barrel, or the rear receiver section, and using same to mount an optical or laser sight. As the launcher would not be used much in ranges over 100-200 meters, this could be easily and cheaply done. It could also be done by an owner of a current slam-fire in order to improve accuracy.

2.  Extraction of the first fired case was a bit difficult, after firing the first round as the video shows. (proof the T&E is not staged). I assume some of this might have been due to the 6’2” 250 large muscular dude that was conducting the test firing slamming the front tube back, perhaps a bit over zealously… Ideas were shared concerning a fix to this minor problem.

3.  In order to fire 26.5mm rounds in the launcher, you need an adapter. This adapter must hold the 26.5mm round in firing position inside. Once the adapter is corrected for length, and holding, it should work very well.

4.  One other recommendation and this one is completely up to MLR is, I recommended engraving the rear tube of the launcher with the company name, address, phone number, and a serial number. I say that, only because if someone wants to use this in LE/Corrections, they will need to register it as a DD, and it is much easier if that information is already on the launcher, plus it’s good for business.


The best part of this launcher is simplicity. It will work, period. There are no parts that can break, and cause the launcher not to function. This is important in life saving signaling situations, as well as LE/Corrections uses. When you need a launcher that will work all the time, every time, I recommend the Slam Fire, made by Mark at MLR Distributing.


A bit of information on the owner, Mark Rogers. Mark has been making these launchers for 15 years. This version of the Slam Fire is a re-design, and parts that were once cast, are now machined steel. Mark warrants all his products with a lifetime guarantee on workmanship. If Mark cannot fix your problem, he will replace it free of charge, unless the unit is misused. (don’t use it to prop up your Jeep when you change tires.) Mark offers dealer prices on his products. Contact him for details.

Above is a photo of the soft shell case Mark will be selling with his extended stock launcher. Contact him for pricing on this style, and case cost.

MLR also manufactures 37mm to 26.5mm adapters in lathed aluminum. The cost of the short adapter is $20.00. The sample provided is a short version of the adapter, and appears to be well made, and has a thicker rim, consistent with other 37mm munitions. This adapter was tested with 26.5mm munitions and functioned flawlessly.

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Here is a short video of those tests:

MLR makes a nylon bristle cleaning brush that is long enough to clean the barrel of the launcher provided. Cleaning of the launcher is very important, in that a lot of the ammo available for 37mm uses black powder for propellant. The launcher is steel, so if you do not clean it after use, the black powder residue will rust the launcher parts. The best way to clean black powder residue is with plain hot soapy water and this brush. Scrub the barrel well, and clean out the firing pin and receiver area well, and allow them to dry. Then apply a light coat of oil to the inside of the barrel, and receiver group. This will prevent rust, and keep your launcher ready to fire for years to come.


MLR Distributing LLC  PO Box 772751 Orlando FL 32877   407-854-1704

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Last modified: 29 JUN 09