{"product_id":"shs-m4-silenced-bore-up-cylinder-head","title":"SHS M4 Silenced Bore Up Cylinder Head","description":"\u003cdiv style=\"background:#edfaf1;border-left:4px solid #27ae60;padding:12px 16px;border-radius:0 6px 6px 0;margin:0 0 16px;font-size:13px;\"\u003e\n\u003cstrong style=\"color:#1a6b3a;\"\u003eSHS M4 Silenced Bore Up Cylinder Head — a wider port for bore-up work, with a pad to take the piston's impact.\u003c\/strong\u003e Compression parts work as a set, never alone.\n\u003c\/div\u003e\n\u003cp\u003eA bore-up cylinder moves more air, and it wants a cylinder head whose port is opened up to match. Pair it with a standard head and the restriction cancels out most of what the bore-up was for.\u003c\/p\u003e\n\u003cp\u003eThe silencing pad is the other half of the part. It sits where the piston head lands, softening the impact that makes an unpadded gearbox sound harsh.\u003c\/p\u003e\n\u003cp\u003eIt is a matched component rather than a general upgrade. On a standard cylinder it brings nothing, and the pad wears like any other consumable.\u003c\/p\u003e\n\u003ch2 style=\"font-size:16px;color:#1B3A6B;margin:18px 0 8px;\"\u003eSpecifications\u003c\/h2\u003e\n\u003ctable style=\"width:100%;border-collapse:collapse;font-size:13px;margin:0 0 18px;\"\u003e\n\u003ctr style=\"background:#1B3A6B;color:#fff;\"\u003e\n\u003cth style=\"padding:7px 12px;text-align:left;\"\u003eSpecification\u003c\/th\u003e\n\u003cth style=\"padding:7px 12px;text-align:left;\"\u003eDetail\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background:#f5f5f5;\"\u003e\n\u003ctd style=\"padding:7px 12px;border:1px solid #eee;\"\u003eType\u003c\/td\u003e\n\u003ctd style=\"padding:7px 12px;border:1px solid #eee;\"\u003eCylinder head\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:7px 12px;border:1px solid #eee;\"\u003ePlatform\u003c\/td\u003e\n\u003ctd style=\"padding:7px 12px;border:1px solid #eee;\"\u003eM4 \/ M16\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background:#f5f5f5;\"\u003e\n\u003ctd style=\"padding:7px 12px;border:1px solid #eee;\"\u003eMaterial\u003c\/td\u003e\n\u003ctd style=\"padding:7px 12px;border:1px solid #eee;\"\u003eAluminium alloy\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:7px 12px;border:1px solid #eee;\"\u003ePort\u003c\/td\u003e\n\u003ctd style=\"padding:7px 12px;border:1px solid #eee;\"\u003eBore-up\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background:#f5f5f5;\"\u003e\n\u003ctd style=\"padding:7px 12px;border:1px solid #eee;\"\u003eSeal\u003c\/td\u003e\n\u003ctd style=\"padding:7px 12px;border:1px solid #eee;\"\u003eDouble o-ring\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"padding:7px 12px;border:1px solid #eee;\"\u003eDamping\u003c\/td\u003e\n\u003ctd style=\"padding:7px 12px;border:1px solid #eee;\"\u003eIntegrated silencing pad\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"background:#f5f5f5;\"\u003e\n\u003ctd style=\"padding:7px 12px;border:1px solid #eee;\"\u003eSold as\u003c\/td\u003e\n\u003ctd style=\"padding:7px 12px;border:1px solid #eee;\"\u003eSingle cylinder head\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\n\u003ch2 style=\"font-size:16px;color:#1B3A6B;margin:18px 0 8px;\"\u003eGood to know before you buy\u003c\/h2\u003e\n\u003cp\u003eOnly worth fitting alongside a bore-up cylinder. On a standard cylinder the wider port gains you nothing.\u003c\/p\u003e\n\u003ch2 style=\"font-size:16px;color:#1B3A6B;margin:18px 0 8px;\"\u003eFrequently asked questions\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eWhat does bore-up actually mean here?\u003c\/strong\u003e \u003cbr\u003eA wider internal passage, so a larger volume of air can move through. It is only useful when the cylinder it feeds is bore-up too.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat is the silencing pad for?\u003c\/strong\u003e \u003cbr\u003eIt cushions the piston head as it lands, which takes the sharpest edge off the noise a gearbox makes. It is a wearing part and will need replacing eventually.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWill it fit a standard M4 gearbox?\u003c\/strong\u003e \u003cbr\u003eIt is cut for M4 pattern gearboxes, but it is designed around bore-up cylinders. Fitted to a standard setup it is simply the wrong match.\u003c\/p\u003e\n\u003cdiv style=\"background:#fffbe6;border-left:4px solid #f0d060;padding:12px 16px;border-radius:0 6px 6px 0;margin:0 0 16px;font-size:13px;\"\u003e\n⚠ \u003cstrong\u003eNot a standalone upgrade:\u003c\/strong\u003e a bore-up head on a standard cylinder gives you nothing, because the narrow part of the system is still the narrow part.\n\u003c\/div\u003e\n\u003cdiv style=\"background:#1B3A6B;color:#fff;padding:12px 16px;border-radius:6px;margin:18px 0 0;font-size:13px;\"\u003e\n\u003cstrong style=\"color:#fff;\"\u003e💡 Titan Forge Airsoft tip:\u003c\/strong\u003e Change the cylinder, head and nozzle together. Bore-up parts only work as a matched group. Browse \u003ca href=\"\/collections\/gearbox-parts\" style=\"color:#cdd6f4;\"\u003egearbox parts\u003c\/a\u003e.\n\u003c\/div\u003e","brand":"SHS","offers":[{"title":"Default Title","offer_id":53619762659704,"sku":"72902477","price":8.95,"currency_code":"GBP","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0562\/8097\/3450\/files\/s674169275479638617_p3441_i1_w800-Photoroom.jpg?v=1764255187","url":"https:\/\/www.titanforgeairsoft.com\/products\/shs-m4-silenced-bore-up-cylinder-head","provider":"Titan Forge Airsoft","version":"1.0","type":"link"}