Tokyo Marui Detonics .45 Combat Master Assembly and Customization

Last time, I did a disassembly review of the Tokyo Marui Detonics .45 Combat Master.

This time, we'll summarize the points that caught our attention during the review and disassembly process before moving on to assembly and customization.

Points of concern, areas for improvement

I reviewed the Tokyo Marui Detonics .45 Combat Master and found almost no flaws after disassembling it (it's a highly refined product despite its older design).

If I had to point out a flaw, it would be the lack of realism in the exterior finish of the black model (the actual black model often has a blue finish).

In terms of performance, with 0.2g BBs and proper hop-up, the muzzle velocity is around 62m/s, which is on the lower side compared to the average for gas blowback guns as a whole. However, considering it's a compact model, the performance is more than adequate, and it seems unlikely that the muzzle velocity could be increased any further due to the short barrel length.

In terms of performance, the fuel consumption is quite good at approximately 0.14g per round, and it seems unlikely that it can be improved any further.

For these reasons, this time we will proceed with a focus on basic maintenance-level improvements, without setting specific goals, in order to make even slight improvements.

The exterior has an elaborate brass finish even straight out of the box, so it would be a shame to remove the paint; I'll leave it as is.

For reference, the tools used for assembly are as follows:

Frame assembly, customization

First, we'll integrate the trigger into the frame.

If you want to change the trigger, do so at this time. Since it's basically compatible with Tokyo Marui's M1911 series, there are plenty of aftermarket triggers available, so use whichever you prefer.

Apply grease to the sliding parts of the trigger and frame. Since the individual parts are made of metal and resin, use Bellhammer Gold Grease No. 0.

Install the greased parts into the frame (see the disassembly section if you're unsure how to do this).

Next, we'll prepare the inner frame.

There were a few spots that looked like they were getting scratched, so I'll be polishing them.

Polish it with a rotary tool. If you don't have a rotary tool, polishing it with sandpaper will also be effective.

This is the inner frame after polishing.

Similarly, the plate that holds the hammer mechanism is also polished.

This is after polishing.

The preparation is now complete.

Next, we'll assemble the hammer mechanism.

The parts to be installed are shown in the following photo.

Basically, I assemble the parts while applying grease to each sliding surface. Since it's a metal-to-metal sliding surface, I use Bellhammer No. 2 grease.

First, install the knocker spring and sear pin.

Knocker installation.

Hammer assembly.

Shear integration

We'll now assemble the plate that holds the hammer mechanism in place (the photo below is reused from the disassembly section).

The remaining parts, the disconnector, knocker return, and knocker return spring, will be assembled at the same time as the inner frame is attached to the frame.

Assembly image

Insert the inner frame into the frame.

The knocker return spring is easily lost, so be extremely careful when assembling it to avoid losing it.

Insert the hammer pin and shear pin to secure them.

Finally, tighten the two screws on the front to secure the inner frame (the photo is reused from the disassembly section).

This completes the assembly of the hammer mechanism.

Next, we'll assemble the hammer spring housing. Here too, since the parts will be metal-to-metal sliding contacts, we'll use Bell Hammer Gold Grease No. 2.

First, set the leaf spring as shown in the picture below.

Next, attach the hammer spring housing and drive in the pin (the photo is reused from the disassembly section).

After attaching the tail section, cock the hammer and attach the thumb safety.

The remaining parts are the thumb safety, the part that adds a click feel, and the grip, and then it's complete.

The frame is complete.

Slide assembly, custom

First, we'll assemble the blowback engine.

First, let's take a look at Bleach.

Upon examining the bleach, I noticed some areas with severe wear, so I will proceed with polishing.

We'll use a rotary tool to buff this area as well. If you don't have a rotary tool, sanding with sandpaper will also be effective.

This is after polishing.

Next, we'll assemble the nozzle and breech. Before assembling the nozzle, apply Bellhammer Gold Grease No. 0.

After assembling the nozzle, install the nozzle return spring and pin.

Before assembling it into the slide, apply Bell Hammer Gold Grease No. 0 to the inside of the slide where it will come into contact with the nozzle.

Now that the preliminary preparations are complete, we will assemble the blowback engine into the slide.

Install the rails into the slide and tighten the screws to secure it.

Tighten the screw at the rear end of the slide, and the slide assembly is complete.

This completes the slides.

Normally, I would use a lightweight aluminum breech to improve its operation, but I couldn't find anything suitable for the Detonics. Lightweight nylon breeches are available, but I'm worried about their durability, so I'm passing on those.

If you are replacing the rear sight, this is the step you will take.

GURDER Steel Rear Sight for Detonics
There are many other types available, so if you're interested, please take a look around.

Barrel assembly and customization

First, we'll assemble the hop chamber.

If you're replacing the inner barrel or hop-up packing, do it at this time.

In the case of the Detonics, I don't think replacing the inner barrel will significantly improve performance, so you'll likely be more satisfied looking for something to enhance its appearance.

Install the spring and bushing into the inner barrel. Be careful, as the order of these steps is different from other models and is easy to forget.

Before assembling the hop packing, apply silicone grease to ensure an airtight seal.

The key point is to apply enough grease to fill the grooves completely to ensure an airtight seal.

Next, assemble the hop packing and wrap it with sealing tape.

The key point here is to avoid wrapping it too thickly; one wrap is sufficient.

KAKUDAI Seal Tape
This is the standard KAKUDAI product.

Now that the preliminary steps are complete, we will assemble the hop chamber (photos omitted).

The hop-up chamber has a part that slides against the outer barrel, so apply grease to it. I'm using Bell Hammer Gold Grease No. 0 here.

Finally, assemble the outer barrel and you're done.

Complete

Before completing the slide, apply grease to the recoil spring. Since this is metal-to-metal sliding, use Bellhammer Gold Grease No. 2.

Before assembling the parts to the slide, apply grease to the area shown in the photo below, as it slides against the outer barrel. Since this is a resin-to-resin combination, use Bellhammer Gold Grease No. 0.

Now we finally complete the slide and apply grease to the area shown in the photo below. Since this is a metal-on-metal sliding surface between the frame's hammer mechanism and the slide, we'll use Bell Hammer Gold Grease No. 2.

The rail section on the frame side is made of resin and metal, so apply Gold Grease No. 0 to it.

Combine the slide and frame to complete the assembly.

Since we've gone to the trouble, let's complete the maintenance as described in the instruction manual. The maintenance involves spraying silicone spray onto the surface and wiping it thoroughly.

I feel like the atmosphere has changed just a little bit (though I also feel like it hasn't changed that much).

KSC Gun Oil
This silicone spray is highly recommended because it has a large capacity and is cost-effective.

Performance verification

I haven't done any modifications to increase the initial velocity, but I have performed airtight sealing, so I will measure the initial velocity.

The conditions were: a full magazine of HFC-134a, a magazine surface temperature of 22.8°C, a room temperature of 18°C, and 18 rounds loaded (G&G bio BBs 0.2g).

This is the initial velocity with the hop-up amount set to the middle (approximately 0.2g appropriate).

Although it's lower than the out-of-the-box 62.3 m/s, it seems the initial velocity was higher due to favorable conditions during the out-of-the-box measurement.

Second shot

Keep firing, keep firing until the very end.

Although the peak initial velocity didn't surpass the out-of-the-box level, an average increase of 3-5 m/s was achieved.

For something that's only designed to improve airtightness, the effect is quite good.

Fuel efficiency

This is the weight of the magazine with a full tank of gas before measurement.

This is the weight of a magazine after firing 18 rounds.

Using 2.0g resulted in 18 shots, which is 0.11g per shot, a significant improvement compared to the 0.14g out of the box.

Calculating how many shots can be fired with a full gas tank, an empty magazine weighs 153.0g and a full magazine weighs 158.0g, so the amount of gas used is 5g. Since the gas consumption per shot is 0.11g, theoretically it can fire 45 shots, meaning you can now comfortably fire more than two magazines (36 shots).

Finally, here's a video of it in operation (after emptying one magazine).

Tokyo Marui Detonics .45 Combat Master Dry-Firing Custom Video

I think that was quite a sharp move, wouldn't you say?

Tokyo Marui Detonics .45 Combat Master Dry Firing (Normal) Video

Summary

As a result of the customization, the peak muzzle velocity remained unchanged, but the average muzzle velocity measured for one magazine improved by 3-5 m/s, and BB consumption decreased from 0.14g to 0.11g, resulting in improved performance. I didn't expect much of a difference since the out-of-the-box performance was already quite high, but it turned out to be surprisingly effective.

This time, we decided not to incorporate any aftermarket parts, but since the explanation basically involves completely disassembling and reassembling the car, it should be helpful as a reference if you are interested in incorporating any aftermarket parts.

Furthermore, this customization will be quite effective in refreshing older, well-used units.

It takes some effort, but the results are well worth it, so please feel free to use it as a reference if you'd like.

That concludes our custom build of the Tokyo Marui Detonics .45 Combat Master.

Tokyo Marui Detonics .45 Combat Master Black
This is a customized model.

Tokyo Marui Detonics .45 Combat Master Stainless Model
Considering the realism of the actual product, I think the stainless steel model with a sandblasted finish has a better overall feel.

Tokyo Marui Detonics .45 Spare Magazine
Having at least one allows you to change magazines, making it even more enjoyable.

There are surprisingly many anime tie-in items still in stock, so it's worth looking around.

In my 2025 research, I looked for links where you can purchase the product at or below the regular price, rather than at resale prices.