I love my first crossbow, a 2021 10 point Viper S400. I also like to customize my equipment. I would classify these as accessories, not modifications (which would void the warranty).
The first was a lanyard to hold the hand crank in its storage position. I realized the crank was missing after I climbed into the tree stand. I climbed down and backtracked down the hill and eventually found it. It is just a piece of cord tied to the stock with a cord lock. Bungee cord may be an improvement. It is easy, quick and quiet to remove and replace with one hand. I have seen some bows with a velcro strap. Any other ideas out there?
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The quiver attachment lever seemed a little sloppy so I replaced the nut with a small bar of aluminum that has a slot to restrict rotation, now the lever is flipped over then twisted a little bit to get it really tight. I think the bow is quieter now.
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I had some issues with zero drifting, after removing the stock, I found the screws that attach the cantilever scope mount to the rail to be a little loose. To get maximum strength from SHCS in aluminum, there should be steel washers under the heads, so I made a small steel plate that fits under the screws. They have stayed tight but there is still flex in the cantilever mount as has been discussed on here. The photo shows the new steel plates and slighter longer screws.
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The cantilever scope mount moves 1/16" (0.062") with a downward thumb pressure of 14 lb. This does not necessarily affect accuracy but I didn't like it. After looking over the struts on the 2023 model and burris optic at the local shop I decided to make something. It is machined from a single piece of aluminum. It clamps on with 2 short 6-32 screws on each side that go into thin steel plates on the inside of the rail (barrel). There is one additional long 6-32 screw that goes side to side across the bottom half of the rail. The strut attaches to the end of the cantilever mount with opposing 8-32 set screws. The shorter forward assist handle is copied from the 2023 model.
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Vertical deflection is now imperceptible, I measured it at only 0.002" at 14 lb vertical force. Sideways deflection at 10 lb is reduced from 0.029" to 0.001". The brace does not seem to get in the way at all. Accuracy is excellent, perhaps even better than it was before. Took me about 3 days to design make and install in my antique machine shop, I am happy with the result, I suspect it is stronger than the new 10 point struts. It does not extend above the rail so I think I will be able to fit a rangefinding scope if I can come up with the $.
I am just learning this forum and realized downloading photos is much faster on my crappy internet if I first resize the photos.
The first was a lanyard to hold the hand crank in its storage position. I realized the crank was missing after I climbed into the tree stand. I climbed down and backtracked down the hill and eventually found it. It is just a piece of cord tied to the stock with a cord lock. Bungee cord may be an improvement. It is easy, quick and quiet to remove and replace with one hand. I have seen some bows with a velcro strap. Any other ideas out there?
The quiver attachment lever seemed a little sloppy so I replaced the nut with a small bar of aluminum that has a slot to restrict rotation, now the lever is flipped over then twisted a little bit to get it really tight. I think the bow is quieter now.
I had some issues with zero drifting, after removing the stock, I found the screws that attach the cantilever scope mount to the rail to be a little loose. To get maximum strength from SHCS in aluminum, there should be steel washers under the heads, so I made a small steel plate that fits under the screws. They have stayed tight but there is still flex in the cantilever mount as has been discussed on here. The photo shows the new steel plates and slighter longer screws.
The cantilever scope mount moves 1/16" (0.062") with a downward thumb pressure of 14 lb. This does not necessarily affect accuracy but I didn't like it. After looking over the struts on the 2023 model and burris optic at the local shop I decided to make something. It is machined from a single piece of aluminum. It clamps on with 2 short 6-32 screws on each side that go into thin steel plates on the inside of the rail (barrel). There is one additional long 6-32 screw that goes side to side across the bottom half of the rail. The strut attaches to the end of the cantilever mount with opposing 8-32 set screws. The shorter forward assist handle is copied from the 2023 model.
Vertical deflection is now imperceptible, I measured it at only 0.002" at 14 lb vertical force. Sideways deflection at 10 lb is reduced from 0.029" to 0.001". The brace does not seem to get in the way at all. Accuracy is excellent, perhaps even better than it was before. Took me about 3 days to design make and install in my antique machine shop, I am happy with the result, I suspect it is stronger than the new 10 point struts. It does not extend above the rail so I think I will be able to fit a rangefinding scope if I can come up with the $.
I am just learning this forum and realized downloading photos is much faster on my crappy internet if I first resize the photos.
