Weird groupings, 2+2

[Deja]

well i did an extended session today, and the answer is in. 

Bipod.

My groups where worse with better ammo today but they didnt spread like that. More wind today too. 

The fun part with shooting is that when you think you know how stuff is working they stop and you need to start over. 
Im kinda new to rimfire jonnes so not sure what to expect, the groups are better than what my Vulcan 25 could produce but hey I havent shot either indoors and the wind has been merciless this summer.

Think ill bring my streamline .22 if we ever get still day and see how they feel vs each other.

 

[Saltlake58]

OK, help me understand. How did the bipod cause the strange groups? Not sure I understand.

 

[Jonnes]

With rifles that recoil a bipod can become a serious accuracy problem if it's too rigid for instance. Rifles should be able to recoil in a straight line backwards, that's why most shooters prefer a shooting bag. A rigid bipod doesn't allow the rifle to make it's natural backwards motion and makes the business end of the rifle flip because it tends to dig itself in. This flip is something you can't control, and the trick to shooting accurate is (repeatability, hence) complete control of what your rifle does. And even though some people say a rimfire doesn't recoil, fact of the matter is that it does. And even the tiniest bit of recoil can cause muzzle flip that in it's turn can cause inaccuracy. Seen this way to often, even with PCP's.

 

[Saltlake58]

I get the physics of a bipod and how some jump more than others, and that all guns, no matter how small the energy output, do recoil. Newton's laws in effect here.

​There must be some controllable element though to get two distinct groups. I suppose it could be different load on the bipod (pressure on the legs and such) but it still seems odd to create those almost side by side groups. It still just seems odd that you could get two separate groups due to bipod issues. Strange.

 

[Guest]

"Jonnes"With rifles that recoil a bipod can become a serious accuracy problem if it's too rigid for instance. Rifles should be able to recoil in a straight line backwards, that's why most shooters prefer a shooting bag. A rigid bipod doesn't allow the rifle to make it's natural backwards motion and makes the business end of the rifle flip because it tends to dig itself in. This flip is something you can't control, and the trick to shooting accurate is (repeatability, hence) complete control of what your rifle does. And even though some people say a rimfire doesn't recoil, fact of the matter is that it does. And even the tiniest bit of recoil can cause muzzle flip that in it's turn can cause inaccuracy. Seen this way to often, even with PCP's.

I happened upon this at the last rimfire match I went to when borrowing the MD's silhouette gun. I simply held under a bit as the flip was repeatable/predictable. I do agree that bags would have been the better option but again, it wasn't my gun.

 

[Deja]

"Jonnes"With rifles that recoil a bipod can become a serious accuracy problem if it's too rigid for instance. Rifles should be able to recoil in a straight line backwards, that's why most shooters prefer a shooting bag. A rigid bipod doesn't allow the rifle to make it's natural backwards motion and makes the business end of the rifle flip because it tends to dig itself in. This flip is something you can't control, and the trick to shooting accurate is (repeatability, hence) complete control of what your rifle does. And even though some people say a rimfire doesn't recoil, fact of the matter is that it does. And even the tiniest bit of recoil can cause muzzle flip that in it's turn can cause inaccuracy. Seen this way to often, even with PCP's.

Yes this sums it up nicely, I was actually quite surprised on how much my short and light vulcan flip. If you look at benchrest setups they all recoil backwards and then gets pushed forward against a stop to reset for next shot. 

Well thats one thing under control, back to shooting.