OK guys, with all this talk of SCR etc... How about we put a list together of the standard stroke lengths, bore sizes and TP sizes?
I've got ones for a HW 77/97 and a 95 (HW80 + HW35 added) so far.... Would be interested to know them for the 99, 80, 55, TX/Prosport old and new, LGV etc....
I'll need: Model - Bore size (B) - Stroke Length (S) - Transfer Port Diameter x Length (TP) - Piston weight in grams without the liner but with the seal.
Standard rifles Model Bore D (mm) Stroke (mm) Swept Vol.(cc) TP D x L (mm) TP Vol. (cc) SCR Piston(g) Caliber Notes HW77/97 early 25 81 39.76 3x6 0.042 938:1 235 - up to serial number: 1446048 - Some rifles have 2.9, 3 or 3.1mm TP HW77/97 Late 26 81 43.01 3x6 0.042 1014:1 265 - From serial number 1446049 - Some rifles have 2.9, 3 or 3.1mm TP HW95 26 85 45.13 3x15 0.106 426:1 254 - - HW80 30 80 56.55 2.9x11 0.073 779:1 - - - HW35 Early 30 65 45.95 4x26 0.327 141:1 - - Leather seal (up
to serial number 843636)HW35 Late 30 65 43.83 2.8x26 0.160 274:1 - - Synthetic seal (843637 on) TX200 (MK1+2) 25 84 41.23 3.65x9.8 0.103 403:1 a bit more than 225? - Additional Top Hat weight.... not sure of weights. Piston will weigh more due to longer piston rod. TX200 (MK3) 25 98 48.11 3.65x9.8 0.103 470:1 225 - .177 add 27g top hat, .22 add 16g for top hat Webley Vulcan 27 79 45.23 2.5x19 0.093 485:1 - - - Webley Hawke 25 79 38.78 4x16 0.201 193:1 - - - Westlake B2 25.4 80 40.54 4x28 0.352 116:1 - - - HW99S 26 71 37.7 3x17? 0.120 314:1 235 - 225 - 225g piston with seal and no liner. Add 10g if you leave the weight inside the piston. Modified Rifles below HW35LGV 25 71 34.85 4x6 0.075 463:1 - .177 Walther LGV Piston - Conversion by Mick (T 20) HW77/97 early 25 81 39.76 3.9x6 0.072 555:1 235 - TP opened up to 3.9 as suggested by Bigtoe01 HW95 26 85 45.13 3.6x15 0.153 296:1 254 - TP opened up to 3.6 as suggested by Bigtoe01 HW35 Early mod. 30 62 43.83 4x26 0.327 135:1 - - Synthetic seal convention (Chambers etc) model Bore stroke Swept Vol. TP dims 0.042 scr Piston Weight Caliber notes