Offset stocks

[BradY]

Running ideas through my head about my next F class rifle stock. It will be a barrel blocked rig with a 30" 1.25" straight 8 twist barrel, trued remington chambered in 6.5x47L.

Ive been reading about offset stocks for fast twist barrels.

My question is would such a stock design be useful on the mild 6.5 case or is it not going to be of any assistance at all?

Thanks

 

[Keith Glasscock]

No matter how mild the cartridge, there will always be torque (at least that is what Newton tells us). Do you need an offset? I don't know, or have any experience.

Hopefully, someone with some real insight will pop up soon.

 

[DBailey]

I recently spent close to a year and a half working with various size forearm offsets. I can tell you they do reduce the torque effect from the heavy 7mm's, but for every positive benefit there is a consequence that must be worked out.
I can also tell you that they are absolutely not required for any of the normal 6.5mm competition rounds. If your 6.5 has a torque problem with any of the common 3" competition stocks the bag setup is most likely the culprit.

 

[robbor]

there used to be pics here on the home page of a rifle with cool looking stock that the forearm was actually like 8-9" wide and was a handle for carying also. was really cool just a shame there was never any info about it.

 

[BradY]

Thank you Gents.

David, is the consequence you refer to an increase in vertical jump of the fore end? The heavy barrel I expect to negate that. However my main interest with the stock is having it run a very low centre of gravity. That should assist with any torque- not that there is any after shooting the 6.5x47 of a friends this morning.

I think Im going to keep the stock as per normal.

 

[Bobr]

Dave,
If you don't mind sharing what were some of the issue's you had to overcome with using an offset, and was there a sweet spot on a 3" forend as far as offset
Thanks Bob

 

[DBailey]

The offsets didn't show any tendency for increased vertical jump in my testing.
I believe that you are on the right track with a non offset low CG stock that is designed for your gun handling technique.

The most evident issue with the offset is front bag deformation. It's caused by the snap back when the bullet leaves the barrel. With a 7mm it only takes a few shots for it to actually hammer a low spot into the right side of the front bag bad enough to interrupt an F-Class string. Fortunately it's an easy fix. All it takes is a reinforced front bag from Edgewood.
The second issue with the offsets is that it makes the bag setup (and the tracking surfaces of the stock) even more critical than it already is. It's not all that hard to get it correct from a bench but shooting F-Class with the varied firing lines, it can be a challenge to get the rear bag perfectly in line and stable.

In our testing with the offset 3" forend, 1/2" to 3/4" offset is the range that gave the best overall results.

At this point we are not using the offset design. If it gets to the point that you have to run a 230g bullet at unbelievable speeds to be competitive then we may have to rethink the situation.

 

[BradY]

Thanks for the help David, I will stay with the regular style stock.

 

[DBailey]

I realize it's been a few days since this thread was active, but I just ran across the relevant pictures.

This one is the practical offset limit on a 3" forend. It's about 3/4". Anything over that and you start having trouble with the vertical tracking surface. the vertical tracking is equally critical to the horizontal tracking surface in order to stop stock induced stringing.

 

[DBailey]

This is the non offset low CG style that we ended up with. It works with anything from a loose hold to free recoil. There are similar stocks on the market.