AR-15 twice through the magazine flyers?

[TwoEyedJack]

I was at the range testing a new load for my AR that features an upper by PSA, with a 20", 1:7, FN chrome lined barrel. The load features a 52 gr. Sierra BTHP match and H335. I was getting really pretty good groups then I shot two where the first shot had gone through the magazine twice. In each case, the first shot was well outside the other four shots. Here is an example:

Has anyone else seen this? You would think that if the round went through the magazine and fed into the chamber once, going through a second time would not cause any additional upset.

 

[mavracer]

1 in 7 with 52gr is pretty fast and putting bullets on the edge of spinning too fast to stabalize any little thing could cause fliers.

 

[wingman]

May have been some set back of the bullet changing oal. Sometimes minor change will move a group.
The load your using has been excellent for me.

 

[TwoEyedJack]

1 in 7 with 52gr is pretty fast and putting bullets on the edge of spinning too fast to stabalize any little thing could cause fliers.

I tried several heavier bullets, including Speer and Hornday 55 gr. softpoints, Hornady 60 gr. softpoints, and Hornady 68 gr. BTHP and nothing shot as well as these Sierra 52 gr. BTHP loads.

 

[mavracer]

I tried several heavier bullets, including Speer and Hornday 55 gr. softpoints, Hornady 60 gr. softpoints, and Hornady 68 gr. BTHP and nothing shot as well as these Sierra 52 gr. BTHP loads.

Most are gonna work well but when you at the edge of stable it doesn't take much to put you over that edge.

 

[alicepark675]

Hello, there!! I am building an ar 15 matching receiver. It’s just a demo model which I am preparing for my ammunition institute. They want me to make a low range ar 15 receiver. Do you think that I can get cheap material for this project?

ar-15 matched receiver