Help shooting off a backpack

[SquarePizza]

Bipod shooter here, having trouble shooting off of a backpack without the bipod.

Usually I load the bipod a little bit and everything feels stable and I am rather happy the results. However, the bipod sucks when I am laying on 30 inches of snow, so I switched to using a backpack as a large flat support.

But using a bag, my groups have opened up horizontally, and I am not sure why. Maybe my bag is too squishy, it just has my work clothes and a med kit in it. Or maybe it is because I am not used to shooting without a little bit of forward loading pressure. I really don't know, but I would like some advice to using a backpack as a shooting aid.

 

[CampingJosh]

I'll be no help with the bag, but have you considered making the feet of your bipod bigger? I've read several people reference using a frisbee to make the bipod move easily for a second target, and I think the same could be used to keep the rifle above the snow.

 

[coyotegray]

Make sure you're in a natural shooting position. It should feel comfortable and not need any muscle input to be on target. The bag may be a little too high or low and your trying to muscle things into the right position. I like to have as much contact between the bag and the rifle as possible. If the rifle is "slippery" on the bag I have problems. I will either use a shooting rest that mounts to the bag or just have molle pouches positioned so that they provide a saddle for the rifle. Also, it works best for me if the rifle is not quite balanced on the bag, just a bit butt heave and supported by a small sand bag the same as if I'm using a bipod.....

Are using a sand bag or anything else when your using a bipod..?

 

[SquarePizza]

I do use a read bag, and I have thought a lot about using some pouch support. I would like to get a new shooting bag with exterior molle strapping so that I can do this.

I might be muscling the rifle and not realizing it, I will try to pay more attention this weekend when I get out there.

 

[shovelstrokeed]

Although far from expert on the matter, as my shooting is confined to a bipod, I would guess you are having trouble with cant when using the bag rather than a bipod. This is going to cause you to muscle the gun via the hand grip and pressure applied to maintain a sight picture. Have you noticed that the gun is not coming back into sight alignment after recoil? That would pretty much prove the above.
You might want to consider lugging out a chunk of heavy plywood or a floor tile to keep the bipod from sinking into the snow.
That, or wait till Spring.

 

[M40_A1]

This is going to cause you to muscle the gun via the hand grip and pressure applied to maintain a sight picture. Have you noticed that the gun is not coming back into sight alignment after recoil? That would pretty much prove the above.

How the rifle comes out of battery might indicate muscling, but it won't "prove" it.

 

[shovelstrokeed]

OK, I concede, it may not "prove" it but it could certainly be an indicator if it wasn't the case when using a bipod.
I switched from a cheap Harris to an Atlas and noticed some degree of horizontal dispersion when I had the friction too tight on the Atlas and had a bit of cant in my initial setup behind the gun. I was able to make it go away when I slightly loosened the friction and then relaxed into my hold rather than pushing or pulling on the hand grip to force horizontal sight alignment.

 

[SquarePizza]

So I travel over to wal-mart and take advantage of the mall ninja craze and pick up a backpack loaded with molle strapping and attached two triad mag pouches to settle the rifle between. Then I jammed an old pillow in the pack to fatten it up.

Some of the best damned shooting I have EVER done! Wow, I was super happy today.

The only thing I can say different was the the sides had some support, and with the pillow there was not the lumpy filling of my work clothes. I might have been trying to muscle the rifle when the clothes were not positioned right to get on target.

I am going to pull out the pillow and fill with cloths, then retest to check. Though I have already skewed the results because I am consciously looking for muscling.