Stroke lengths, TP sizes and SCR for various springers...

[ricardolamos]

Are you sure HW 35 transfer port lengths are correct as the quoted length is about an inch?

[T 20]

Are you sure HW 35 transfer port lengths are correct as the quoted length is about an inch?

Yes, I'm sure, the HW35 transfer port is about an inch long.

[harvey_s]

My 99s had no piston weight fitted...(bought new 2020)

Did some have them fitted? If so, I wonder how they decided which ones to fit them to...

[TonyL]

As far as I'm aware the HW99 has never had a piston weight fitted as standard. I own two and have assisted in the minor fettling of a couple of other 99s. Not sure if any of them ever had the washer down at the front end of the piston as some HWs reportedly had / have? My guess would still be a "no", though......

[TonyL]

Some excellent information gleaned from the GTA Airgun Forum and Airgun Warriors. Should come in handy for some (and interesting for all springer enthusiasts).

Apologies if there are any duplications and the information is a little more abbreviated, so no piston weights / transfer port dimensions.

Bore (mm) Stroke (mm) Swept volume (cm3)


Benjamin Super Streak - 30, 120, 82.0

BSA "XL" (Lightning / S'Sport?) - 29, 70, 46

Cometa 300 - 26, 80, 42.5

Cometa 220 - 26, 82, 43.5

Cometa Fenix 400 - 26, 100, 53.1

Crosman Quest - 25, 100, 49

CZ Slavia 634 - 25, 77, 37.8

Diana 25 - 25, 55, 27

Diana 31 and 34 - 28, 80, 49.3

Diana 46 - 28, 85, 52.3

Diana 48 / 52 - 28, 100, 61.6

Diana 54 - 28, 105, 64.4

Diana 350 - 28, 115, 70.8

Diana 460 - 28, 114, 70.2

Gamo 610 - 25 , 85 , 41.7

Gamo Delta Fox - 25 , 61 , 29.9

Gamo Shadow 640 - 25 , 90 , 44.2

Gamo CFX, 440, 890, 220, Whisper, Shadow 1000, Viper, Elite, CF20 and CF30 - 25 , 100 , 49

Gamo 1250 - 29 , 118 , 77.9


Hatsan 70 - 27 , 100 , 57.3

Hatsan 105 - 27 , 100 , 57.3

Hatsan 55S Magnum - 27 , 103 , 59

Hatsan 60S - 27 , 100 , 57.3

Hatsan 80 - 27 , 98 , 56.1

Hatsan 125 - 29 , 120 , 79.5

Hatsan 135 - 30 , 120 , 87

Industry AR1000 - 26 , 107 , 56.8

IZH 22 - 25 , 62 , 30.4

IZH 38C - 25 , 51 , 25

IZH 53M - 25 , 40 , 19.6

IZH 60 - 25 , 57 , 28.0

IZH61 - 25 , 57 , 28.0

IZH MP 512 - 25 , 82 , 40.3

IZH MP513 - 28 , 120 , 73.9

Norica Dragon, Storm, Marvic Gold - 26 , 100 , 53.1

Perfect a 50 - 25 , 75 , 36.8

Remington Genesis 1000 - 29 , 82 , 54.2

Webley Patriot - 30 , 114 , 80.5

Weihrauch HW57 - 26, 81. 3mm x (18mm?) TP - courtesy of Robs 5230

Weihrauch HW98 - (as per HW95) - 26 , 85 , 45

Weihrauch HW90 Gas Ram - 30 , 106 , 75.

Guessing also that the differences in stroke lengths shown for the Hatsan 55, 60 and 80 will be down to measuring inaccuracies and that they share the same strokes?

[harvey_s]

Not sure what use SCR is on it's own?
Surely piston weight and acceleration are major factors along with rifle mass

[TonyL]

Not sure what use SCR is on it's own?
Surely piston weight and acceleration are major factors along with rifle mass

I agree and there are so many inter-related factors contributing to the efficiency and firing cycle of the springer. As we all know it's all a question of balance. However, the SCR can be a useful indicator in terms of efficiency. For example, the HW77 has a high SCR and is regarded as an efficient power plant. The B2, with its high TP volume as standard, benefits from a raising of the SCR via reducing the transfer port diameter, as Mick (T20) found.

[Shed tuner]

Weihrauch HW90 Gas Ram - 30 , 106 , 75.

that's the fac version, UK stroke is ~80mm

[TonyL]

Cheers JB.