Rear Bag Settling Tricks?

[CharlieNC]

When shooting a Ftr match my rear Protektor bag tends to settle quite a bit, as in several MOA. I have continued to add sand over time and it will not pack any more. For storage I insert a board where the stock rides between the ears, and hammer it down; but this has not helped. To continually adjust the bipod during a match is distracting, and it is easier to squeeze the bag to restore proper elevation. I have read someone added a little cement and water for packing, but I worry this may result in too hard with little buffering. Any suggestions?

 

[RED 7]

When shooting a Ftr match my rear Protektor bag tends to settle quite a bit, as in several MOA. I have continued to add sand over time and it will not pack any more. For storage I insert a board where the stock rides between the ears, and hammer it down; but this has not helped. To continually adjust the bipod during a match is distracting, and it is easier to squeeze the bag to restore proper elevation. I have read someone added a little cement and water for packing, but I worry this may result in too hard with little buffering. Any suggestions?

Do you have the correct width bag to match the width of your stock?

 

[Immike]

Are you adjusting the bipod up or down?

 

[CharlieNC]

I have a custom bag that fits well; it's the sand in the bottom that is settling. This raises the muzzle which requires lowering the bipod. As mentioned I can squeeze the bottom of the bag, not the ears, to raise it sufficiently. Not holding the squeeze, just restoring the packing height of the sand.

 

[dmoran]

Myself suggest to fill it more/tighter/fuller.
Also suggest to run on the stitching and not at all on ears.
My 2-cents
Donovan

 

[CharlieNC]

Myself suggest to fill it more/tighter/fuller.
Also suggest to run on the stitching and not at all on ears.
My 2-cents
Donovan

Thats where I am now Donovan on both points. Can't get any more sand into it though. Ear spacing is perfect and running on the stitches. Before shooting I pressure the stock to pack as much as possible. A couple moa movement isn't much on the bag, but is on the target.

 

[dmoran]

What are you using for sand/fill ?

 

[CharlieNC]

What are you using for sand/fill ?

I ordered it with their heavy sand. But been adding a small amount of playground sand to finish packing it as tight as possible.

 

[dmoran]

@CharlieNC
Not positive (because I've never mixed sand types) but feel that could be in part why.... just saying
Donovan

 

[CharlieNC]

Maybe a vibration table would pack it tighter to allow more sand to hold the tightness.

 

[dmoran]

@CharlieNC
Worth a try..... IMO

Good Luck
Donovan

 

[Immike]

I have a custom bag that fits well; it's the sand in the bottom that is settling. This raises the muzzle which requires lowering the bipod. As mentioned I can squeeze the bottom of the bag, not the ears, to raise it sufficiently. Not holding the squeeze, just restoring the packing height of the sand.

Try standing on end by clamping the side edge in a vice to finish filling the squeeze out of it. Use a 1/16 tamping rod to push in a small amount at a time instead of filling the funnel just add a teaspoon and then another until it's full... Shake ,then do it again.

 

[randy x]

Watch who wins all the time setup.

 

[Average joe]

Pound your buttstock into the bag before you start your string.
Not a cure , but will minimize its affect during the relay.

 

[Immike]

Pound your buttstock into the bag before you start your string.
Not a cure , but will minimize its affect during the relay.

Joe is right on. If I'm on grass I will get it all in place then wrap my hands around the outside edges and throw my body weight on the bags base a few times to push it down as far as possible. Then pound in the stock and then adjust the front. Set up from the ground up and it will stay.

 

[CharlieNC]

I will try all of the above. Thks guys.

 

[Alex Wheeler]

I will try all of the above. Thks guys.

Its probably not the bag but the surface its on. Off the bench we dont see that kind of movement and the bags dont have to be filled like a rock either. Most times the ears are filled too much and squeeze the butt up and out of the bag. If you have to pound the stock into the bag take sand out of the ears. Most the time the ears will be soft and when you push the stock into them they tighten up. Ears guide the stock left and right, the bag is the vertical unless the ears are filled too much.

 

[CharlieNC]

Its probably not the bag but the surface its on. Off the bench we dont see that kind of movement and the bags dont have to be filled like a rock either. Most times the ears are filled too much and squeeze the butt up and out of the bag. If you have to pound the stock into the bag take sand out of the ears. Most the time the ears will be soft and when you push the stock into them they tighten up. Ears guide the stock left and right, the bag is the vertical unless the ears are filled too much.

Alex my shooting is primarily on a concrete pad. The bag fits properly, and the bottom is clearly settling ever so slightly. I do not think this would occur if shooting free recoil, but with a bipod my style is to impart a slight cheek pressure which probably contributes.

 

[Alex Wheeler]

Alex my shooting is primarily on a concrete pad. The bag fits properly, and the bottom is clearly settling ever so slightly. I do not think this would occur if shooting free recoil, but with a bipod my style is to impart a slight cheek pressure which probably contributes.

Does your stock have drop in the butt? If the bag slides forward as they can tend to do it will give the effect as if it was settling. If you have it packed as hard as you say I would be very surprised that it was settling. Just by definition if you cant fill it anymore than how can it be settling? Settling would imply theres room for the sand to move around.

 

[LHSmith]

This issue is adressed in Ratigan's book "Extreme Rifle Accuracy". When I first started shooting SR BR using "heavy sand" was the norm. I also has the same issues with bag settling. You want sand that is course and irregular in shape that resists settling. As explained in the book, attempting to expect the rifle to remain stable while resting it on a pile of small marbles will be an effort in futility. Speedy G. had similar problems with heavy sand in the front bag that it packed too hard (causing vertical issues) and devised years earlier his "speedy mix" (google it) which contained parakeet gravel which is course and irregular in shape. I have found that blasting media from TSC is even better.
FWIW the heavy sand as sold by Sinclair - the black stuff- is better at minimizing settling than Zircon-the white stuff.