Fitted a Tinbum Tuning kit to my HW30 and found that the gun wouldn't cock. I had to grind a bit off the spring length to cure the problem. Since then I have heard that a lot of Weihrauch pistons contain internal weights. I didn't check. Can anyone with an HW30 confirm or deny this, please.
Weihrauch HW30 / Beeman R7 piston weights
- Thread starter Bulls-eye
- Start date
Never heard of a HW30's having internal piston weights, matter of fact no Weihrauch has internal piston weights.
- When installing a tuning kit:
1) Measure the internal length (space) of the piston.
2) Measure the thickness of your springs wire and multiply the number of coils x the wire thickness.
4) Determine how much length a fully compressed spring displaces and subtract from internal piston space.
5) That amount determines if the spring + and top-hat is too long ... as the spring set-up needs to fit inside the piston for the gun to cock.
6) Lastly, if the spring guide + internal top-hat part (inside spring) exceed the piston length, the gun will also not cock.
Basically, if the piston cannot completely touch the rear (black) plug (holding the Trigger) - the piston tang cannot engage (or lock) into the trigger sear and hence the gun won't cock.
- When installing a tuning kit:
1) Measure the internal length (space) of the piston.
2) Measure the thickness of your springs wire and multiply the number of coils x the wire thickness.
4) Determine how much length a fully compressed spring displaces and subtract from internal piston space.
5) That amount determines if the spring + and top-hat is too long ... as the spring set-up needs to fit inside the piston for the gun to cock.
6) Lastly, if the spring guide + internal top-hat part (inside spring) exceed the piston length, the gun will also not cock.
Basically, if the piston cannot completely touch the rear (black) plug (holding the Trigger) - the piston tang cannot engage (or lock) into the trigger sear and hence the gun won't cock.
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I'm not sure what you mean by internal piston weight. On some models Weihrauch puts a washer atop the spring to hold the grease shield in the piston. Other than that I've never seen an additional weight deliberately added to one of their springers.
The Weihrauch HW90 which doesn't have spring, does use an internal piston weight. They call it an inertia weight. It's to prevent piston bounce.
The Weihrauch HW90 which doesn't have spring, does use an internal piston weight. They call it an inertia weight. It's to prevent piston bounce.
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How old is this HW30? Something tells me the pre safety R7's might have had a different piston. Paul Watts talks about earlier R7 differences in his videos. Does your '30 have a leather seal? That would be earlier than an R7.
A "little birdie" told me the HW90 inertia piston was only a gimmick that allowed Theoben to extend their pattent.
A "little birdie" told me the HW90 inertia piston was only a gimmick that allowed Theoben to extend their pattent.
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I bought a used RX1 that was hardly shot and sat almost twenty years before I got it. It was overcharged from the factory and burnt out the seal shortly after I got it. Long, long story short during the rebuild I found inertia weight stuck and inoperative. I spent a lot of time and money to get the gun right. Somewhere in the process I ran it with and without the inertia weight and found no noticeable difference in shot cycle or power. I did notice a big difference in extreme spread. The gun before hand with a new seal and the occasionaly sticking inertia weight had ES of 50 or more. Not satisfied with that I honed the piston ID, tried different seals, orings and lubes. I also ran it with and without the inertia weight. My best ES without the weight was about 25. With the weight it was 6.
The gun was a total pita to get right but when I was done with it, it'd consistently shoot quarters at 50 yards.
I since have a higher appreciation for the HW90 than most. Including the Elite trigger. It's like anything else, the more familiar you are with something, the better your results. The better your results the more you like something.
Okay maybe it was still a long story. Trust me this was the abbreviated version.
Be well
Ron
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I watched the video. I caught his comments about the piston weights/o-rings. I have yet to find a weight or o-ring atop a spring. Maybe its a UK market thing. I don't know. I've opened up Beemans and Weihrachs from 82 on and never seen a weight or oring
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