Linear / Sliding Bipod - Linear Bearings

F/TR is the international full bore class for .308 and .223, currently being trialled around Australia.
majaci@bigpond.com
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Linear / Sliding Bipod - Linear Bearings

Post by majaci@bigpond.com »

Hello fellow FTR shooters,

What is general consensus regarding the use of a bipod that does not slide during the shot, rather it has a sliding bearing allowing the rifle to slide?
Would this breach any of the FTR rules? Has this happened before?
It does not return the gun to previous firing position in any way however it does enable the rifle to track straight back. Views and oppiions?

Video illustrating what I am talking about is here.

https://www.youtube.com/watch?v=A34f1Heb5pY
Daveh
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Re: Linear / Sliding Bipod - Linear Bearings

Post by Daveh »

I made a concept one with a small 12mm linear rail and one bearing block similar to the video mid COVID in 2020. The biggest issue was the weight. Even using carbon tube legs it was too heavy. I had the idea of 50mm spikes on the legs and "plant" them in.

Even milled the back of the steel rail to drop the weight.

Gave up as a pair of sleds on the bipod legs allowed me to stay under weight without needing to change to a lighter barrel.

Can't comment if it would be allowed in regards to the rules though.

Dave
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Re: Linear / Sliding Bipod - Linear Bearings

Post by BATattack »

Yes and no. As you say it will never perfectly return to battery. Is it an unfair advantage. . . Maybe. As mentioned above yes you might end up with a system that tracks better but you will have to sacrifice some weight somewhere.

Best thing to do is build it and wait until you start winning stuff then fellow competitors and ROs will help you decide if it's legal :-)
Barry Davies
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Re: Linear / Sliding Bipod - Linear Bearings

Post by Barry Davies »

FTR rules state that the bipod must be "Attached " to the rifle.

"Attached " is further defined as something that Recoils or partially recoils with the rifle. Not sure what " Partially " means --it either recoils with or it does'nt.
I would consider it illegal. ( for FTR )
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Re: Linear / Sliding Bipod - Linear Bearings

Post by BATattack »

Barry Davies wrote:FTR rules state that the bipod must be "Attached " to the rifle.

"Attached " is further defined as something that Recoils or partially recoils with the rifle. Not sure what " Partially " means --it either recoils with or it does'nt.
I would consider it illegal. ( for FTR )


I would say that's it's attached because when you lift the rifle it comes with the rifle.
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Re: Linear / Sliding Bipod - Linear Bearings

Post by Barry Davies »

Maybe so ,but it does not recoil with the rifle as is defined in the rules.
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Re: Linear / Sliding Bipod - Linear Bearings

Post by BATattack »

Ok if you want to focus on that section of the rules. If the linial rail is "part" of the bipod then it would be recoiling with the rifle. So the bipod would be "partially" recoiling with the rifle.

Even if the above wasn't true would you be able to say that the remainder of the bipod is absolutely stationary and does not even partially move during recoil?
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Re: Linear / Sliding Bipod - Linear Bearings

Post by Daveh »

The one I experimented with still managed to lift the left bipod leg up due to the torque
It was all good for the first 1/2" of movement back and the bullet would have left the barrel. Using 200gn projectiles there was still more recoil to manage after that.
The weight was the problem.
Dave
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Re: Linear / Sliding Bipod - Linear Bearings

Post by Barry Davies »

If the bipod moves , even partially, then does this not defeat the whole purpose of the design?
The linial rail is certainly part of the rifle, because it is " attached " to the rifle. The bipod part is not " attached" to anything.
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Re: Linear / Sliding Bipod - Linear Bearings

Post by BATattack »

The rail could be incorporated into the bipod design and therefore the bipod would be attached to the rifle. Saw something similar years ago.
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Re: Linear / Sliding Bipod - Linear Bearings

Post by GrahamW »

Barry Davies wrote:If the bipod moves , even partially, then does this not defeat the whole purpose of the design?
The linial rail is certainly part of the rifle, because it is " attached " to the rifle. The bipod part is not " attached" to anything.


On the other hand..... would you say your wheels are attached to your car?
I would, yet they move (rotate) independently. :-k
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Re: Linear / Sliding Bipod - Linear Bearings

Post by PeteFox »

IMO
If it doesn't recoil with the rifle then it is not "attached" within the meaning of the rules.
Pete
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Re: Linear / Sliding Bipod - Linear Bearings

Post by BATattack »

Was it Vivian who used to / still has a bipod that has a sand bag on the top. Gun slides in the sand bag. When you pick the gun up the bipod is "attached" because the bag keys over the forend of the stock. Similar principal
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Re: Linear / Sliding Bipod - Linear Bearings

Post by CBH Australia »

Sounds like a lot of work to make one that works well.
As for being permitted I guess you need to research the rules a little and be clear on the definition and interpretation as many will interpret things differently.
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Re: Linear / Sliding Bipod - Linear Bearings

Post by Tim L »

Good luck getting any clear direction on SSRs.
If people put as much effort into shooting that they put into the linguistic gymnastics to get the outcome they want, Australia would dominate the sport,,,, more than we already do.
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