Discussion in 'Steyr' started by hmangphilly, Apr 12, 2019.
Almost the same but not quite
Steyr is the fatter body and fatter spring Pip
Have you tried weighing the two hammers, my guess is that the Anschutz is lighter so only needs a smaller spring?
What about the orings?
The ports are 4.1 steyr and 4.0 anschutz
The valve mass shouldn't really have much of a relationship with the necessary spring spec IMO
Indeed - the most important value here IMO is the ID of the O-ring once compressed and hence the pressure loading across the valve when closed / force required to open it, curtain area, lift required to achieve full flow and all that good stuff
Very interesting that they're so similar in format and yet different. Are their stems the same diameter?
Quite telling of the guns' origins and development IMO; as large as they can / need to be for sub 12ftlb (and more likely sub 6ftlb) use but a bit smaller than would be ideal for high output.
This is one of the facets I love about the LG110; the port sizing is large enough to give the best performance with different pellet weights at the required muzzle energy output while not being so excessively large as to require more energy to open the valve than necessary.
Shows some proper thought was put into the process by some knowledgeable people, rather than just plucking arbitrary figures out of the air like "some other" manufacturers seem to do..
I spelt anshuts wrang in the titttle.
I noticed this but didnt mention it as you seem quite clever and i didnt want to discourage you
oh what have you done...
Stems the same dia 1.48 mm
Heads give or take 8 mm steyr , 7.5 anschutz
O rings different size
Both. Seem 1 mm ish section
Hard to measure sizes because they've been squished and swaged
But kinda sorta
4.5 I d / 6.3 od steyr
4mm id / 5.4 od anschutz
the steyr o ring sits less pronounced than the anschutz..possibly less temp affected because of that .
the anschutz o ring inner edge is really close to the port
i have taken a steyr valve down to around the same dia as the anschutz
I wud o thought yad'a scrubed yer fingernails after yer date with Dave, Wots that brown stuff.
Interesting that the Steyr hammer is heavier and longer. I’m still amazed how long that sucker is in comparison with the Anschutz one.
It has to be that long cos the spring is a long way from The valve
Interesting! From the valve O-ring sizes it looks like the Anschutz valve is a closer match to the valve throat; which is a good thing as it will reduce valve opening load (by nearly 25% if we're talking 4.0mm ID versus 4.5mm on the Steyr) while not choking flow at the throat.
When measuring mine IIRC I found the Steyr's valve throat to be around 4.25mm diameter; giving an area of around 14.2mm^2, or 12.4mm^2 flow area once the 1.8mm^2 area of the valve stem has been taken into account. This is pretty well matched to the 12.6mm^2 flow area of the 4mm porting throughout the rest of the system.
I imagine Steyr back-worked the port size from the bore - make the port 0.5mm smaller on the OD than the smallest bore to prevent the pellet falling into it, make the valve stem as small as possible without compromising strength, make the throat whatever diameter is necessary to give the same flow area as the porting then spec the next standard size up for the O-ring in the valve.
Going as large as possible on the port ensures the lowest operating pressure (so more shots per charge) and minimal sensitivity to pellet mass.
Am I correct in thinking that the LG100 series started out as a dedicated 10m gun (so .177, 6ftlb only) before they released the higher output "adventure" / Hunting / FT guns? Would figure as the porting is ideal for .177 but a bit lacking for .22 - especially at the 40J they knock them out at.