Bag rider forend, how long and a rest question:

[eric32]

Just giving you options, but you could do the same with a set rings. And a 1 inch carbon fiber tube with another pic rail attached for a bipod or bag rider.

 

[kthomas]

I wouldn't waste your time. Get a more fit for purpose chassis for what you are trying to do.

Having a really long cantilevered "bag rider" is going to cause some vertical dispersion issues. Not very conducive to precision and repeatability for ELR.

People are seeing this with the thin aftermarket ARCA/RRS rails on PRS rifles that overhang the stock/chassis by a few inches, with a bipod placed at the end unsupported section of the rail. With what you want to accomplish, you are going to exasperate the issue even more.

 

[DHuffman]

You are probably right but I'm making my forend out of 80/20 extrusion that is 3" wide and I have already bought a matching 3" bag.

I don't know of an easy to fit extrusion that is 4" wide. I bet 3" will be a bit less annoying to case also.

3" works out.

Buy a set of @Field & Cave 3" to 4" conversion rails for your 3" bag rider.

 

[Dud]

I wouldn't waste your time. Get a more fit for purpose chassis for what you are trying to do.

Having a really long cantilevered "bag rider" is going to cause some vertical dispersion issues. Not very conducive to precision and repeatability for ELR.

People are seeing this with the thin aftermarket ARCA/RRS rails on PRS rifles that overhang the stock/chassis by a few inches, with a bipod placed at the end unsupported section of the rail. With what you want to accomplish, you are going to exasperate the issue even more.

My bag rider forend will be supported by the height of the extrusion, bedded to the chassis with Devcon 10110 and bolted in with 4 screws.

It will be stiff and it will be solidly attached.

I thought about using a long section of Arca rail but decided against it for those reasons.

I'm not going to buy a new chassis so this is it, I just want to know how long I need to make it to properly use a benchrest.

 

[eric32]

it makes sense to go as long as possible without sacrificing rigidity, also you can tailor weight to make the balance point to where it tracks straight back and doesn't bounce around when your on the bags.

please do show some groups and pictures of the rifle when you're done

 

[kthomas]

My bag rider forend will be supported by the height of the extrusion, bedded to the chassis with Devcon 10110 and bolted in with 4 screws.

It will be stiff and it will be solidly attached.

I thought about using a long section of Arca rail but decided against it for those reasons.

I'm not going to buy a new chassis so this is it, I just want to know how long I need to make it to properly use a benchrest.

It may be attached solidly, but if it's long with the majority of the rail itself unsupported, it's going to have a lot of flex and cause vertical dispersion issues.

See this rail here, and how there is a little bit of rail unsupported at the end with the bipod off of it? That is enough to cause vertical dispersion issues:

If you make more of that rail unsupported, the vertical dispersion is going to be even worse.

 

[Dud]

This is the extrusion:
View attachment 1133533
It will not suffer from the problem you describe because it will have some height to the cross section.

It will be cantilevered but the junction is going to be much stiffer than what you pictured.

It's just not an issue.