SHS Bore Up Nozzle — M4, 21.4mm

SHS Bore Up Nozzle for M4 Builds — the wider bore, for an M4 running a bore-up cylinder. Not a standard M4 nozzle. Fitting a bore-up cylinder changes the volume of air the gearbox moves, and the nozzle has to be able to pass it. A standard nozzle becomes the restriction in that chain. This is the M4 nozzle opened out to suit, at 21.4mm long. The length matches the platform; what differs from the standard part is the bore through the middle. Bore-up is a matched conversion rather than a single upgrade. Cylinder, cylinder head, piston head and nozzle all want to be specified together or the extra volume goes nowhere useful. Specifications Specification Detail Part Air nozzle Platform M4 and M16 Length 21.4mm Bore Bore-up Manufacturer SHS Sold as Single nozzle Good to know before you buy Length alone will not tell you what you already have. M4 nozzles commonly sit around this figure whether they are bore-up or standard, so the bore is what distinguishes them and it is worth checking before ordering. Frequently asked questions Do I need this if I have not fitted a bore-up cylinder? No. On a standard cylinder it gives you nothing, and the standard M4 nozzle is the correct part. Is the length different from a standard M4 nozzle? The length is the same at 21.4mm. It is the internal bore that differs, which is what lets the extra air through. Does it come with an o-ring? Our supplier does not state one, so keep the seal off your old nozzle until this one is in front of you. ⚠ Bore-up is a set of parts, not one: a bore-up nozzle on a standard cylinder achieves nothing, and a standard nozzle on a bore-up cylinder throttles the whole conversion you paid for. 💡 Titan Forge Airsoft tip: Write down what is already in the gearbox before ordering any of it. Bore-up builds go wrong most often because one part in the chain stayed standard. Browse gearbox parts or message us.