Need Help: Random ‘slow’ rounds

[TaperPin]

I’d bet lunch it’s an ignition problem - either dirty firing pin, bolt cocking piece dragging on the trigger, week firing pin spring, or weird batch of primers. If you’ve ever blanked a primer (had a hole in the primer) a small brass disk can blow back through the firing pin hole and cause problems.

I had a partially frozen bolt that had to be recocked a couple of times before it fired and it was almost 2 MOA outside where it should have been.

 

[LaHunter]

I haven’t chronoed all of those 400 rounds… that probably sounded misleading. But results at distance have been consistent. Meaning I may have had slower rounds but didn’t hear the difference or see rounds fall way short.

Largest sample size I have chronoed is 12 rounds.

Yesterday I was shooting at distance and the rounds did not fall within the cone of the rest of my rounds. I could hear the difference and didn’t see my impacts which is when I looked at the chrono

If you could hear the difference in these slow rounds, I’m assuming you could maybe feel less recoil? If so, the logical explanation is you somehow undercharged these rounds.

 

[Megalodon]

Reloading is very monotonous for me, and as much as I try to not be distracted by tv/phone etc. while I'm dropping charges, it happens. I ran into an issue a little while back where I would have wildly off rounds. But it wasn't consistent, and would only be 1 or 2 out of a batch of 100, and maybe 5-600 rounds apart.

When I finally decided to figure out WTF was going on I assumed my thrower was undercharging. But really it was powder getting caught up in the funnel I was using, resulting in a light charge. Then I would think my next round was a double charge, because you know... not paying close enough attention.

No idea if that is relevant, but it's my story.

I tap and make sure the funnel is empty now, and also give most rounds a little shake after seating the bullet to check powder fill.