AirsoftPro TDC hop-up regulator, for 26mm outer barrels

TDC stands for “Top Dead Center”. The term is used in engines to describe the highest possible position of the piston in the cylinder. In airsoft, it refers to a device that is able to continuously press (usually with an adjustment screw) the top of the hop-up chamber lever. This creates a clear upper limit (TDC) for the lever, thus avoiding unwanted movement. In addition, the adjustment is more sensitive, smoother and usually wider than with traditional lever adjustments.

AirsoftPro's TDC is a simple device that fits many airsoft precision rifles. By turning the knob, the pressure on the chamber lever is changed and the bullet trajectory, or hop-up, is adjusted. The device offers the user greater accuracy and convenience than traditional screw or lever adjustments. There are two models available, which differ in length, location of the mounting screw, and lower arch to match the barrel diameter. See the table below.

The TDC device is made of precision CNC machined aluminum alloy and consists of two main parts: the base and the adjustment ring. The device is placed on the outer barrel, just above the hop-up chamber. Its low profile does not interfere with larger scopes. The TDC is not usually pre-installed on guns and cannot simply be attached and screwed into place. Installation therefore requires partial disassembly of the barrel, measurement of the hop-up lever position, and drilling a hole in the outer barrel exactly above the lever. The TDC adjustment screw passes through this hole. By turning the screw, its length changes, raising or lowering the chamber lever.

Most often, the TDC must be glued onto the barrel with instant glue. An M3x10 screw is included, which can be used to screw the device through the barrel into the chamber. Screwing is naturally a better method of attachment than gluing, but only a few original chambers have a pre-threaded hole. For example, Well MB01/04/05/06/08/13 chambers and new AirsoftPro chambers already have such a thread, making it easy to install the TDC.

A spirit level not only makes it easier to accurately set up the device, but also to shoot. Tilting the gun to the left or right causes the bullet to curve to the side and become inaccurate. With the help of a spirit level, this error can be easily corrected.

Features:

• Precisely CNC machined
• Rounded edges to avoid snagging on equipment
• Sensitive adjustment (1 full turn = 0.5 mm movement)
• Lockable adjustment position of the adjustment ring - 26 steps per revolution, single step adjustment movement 0.02 mm
• Integrated spirit level
• Can be screwed to some of the chambers, others are attached with instant glue
• Suitable for 27-30 mm outer pipes

AirsoftPro TDC models

Name	Product code	Dimensions	Weight	Approximate diameter of the outer pipe	Axial distance of the fixing and adjusting screw
26mm TDC Hop-Up adjuster	8995	46.8 x 17 mm	15.71g	26mm	30mm
30mm TDC Hop-Up adjuster	9004	36.5 x 17 mm	12.33g	30mm	5mm

Compatibility table:

Brand	Quid	Recommended TDC model
A &K	M24	30 mm (SKU 9004)
ASG	McMillan M40A3	30 mm (SKU 9004)
APS/Hakkotsu	APM40A3	30 mm (SKU 9004)
CYMA	CM.700, CM.701, CM.703, CM.706, CM.707, CM.708	30 mm (SKU 9004)
CYMA	CM.702	26 mm (SKU 8995)
Double Eagle	M40A3	30 mm (SKU 9004)
E & C	L96	30 mm (SKU 9004)
JG	BAR-10 / BAR-10G	30 mm (SKU 9004)
Modify	MOD24	26 mm (SKU 8995)
Novritsch	SSG10	26 mm (SKU 8995)
S &T	M40A3, M40A5	30 mm (SKU 9004)
Snow Wolf	M24	26 mm (SKU 8995)
Specna Arms	SA-S02 CORE	30 mm (SKU 9004)
Tok yo Marui	VSR-10 / VSR-10 G-Spec	30 mm (SKU 9004)
Well	MB01, MB04, MB05, MB06, MB08, MB13, MB14, MB15	26 mm (SKU 8995)
Well	MB02, MB03, MB07, MB09, MB10, MB11, MB12, MB16, MB17	30 mm (SKU 9004)
Well	MB4401, MB4402, MB4403, MB4404, MB4405, MB4406, MB4407, MB4408, MB4409, MB4410, MB4411, MB4412, MB4413, MB4414, MB4415, MB4416, MB4417, MB4418	30 mm (SKU 9004)

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