Deburring Flash Hole Question

[NoAngel]

I have seen noticeable improvements from deburring flash holes. Bordering on significant improvements.
I do it to everything I load.

[Hardcast416taylor]

I started deburring my primer pockets in the case with a #1 starter drill turned down and welded to a small rod to fit in the case mouth way back in 1970 when I shot more and went for precision at distance. Now I use a Sinclair de-burr tool (not sure they still make it) for my case prep work, I threaded the shaft to screw onto my RCBS case prep center machine. The RCBS tool is better than nothing but you can`t be sure the de-burr tool tip is in the flash hole by its design.Robert

[Moonie]

It will not turn a 4MOA rifle into a 3MOA rifle, but it can help a rifle that is capable of sub MOA, I've seen it.

[NoAngel]

It will not turn a 4MOA rifle into a 3MOA rifle, but it can help a rifle that is capable of sub MOA, I've seen it.

Exactly. The biggest most noticeable thing for me was the random flyers disappearing. Every couple of groups I would get a flyer a half inch out or so. Very Very rare these days on proven loads.

[Avenger442]

my guess is that's it. I found by deburring the flash holes on the magtech 24 gauge shotshell brass I use for the 577 snider, I get MUCH better ignition and burn of the powder, along with way more consistent loads. should prove to be true in this case as well.

Last range trip seems to verify that. Dropped the powder load a little and groups with the .308 at 100 yards shrunk to 1 1/2". That's significantly better. Have to go back and load up several more same cases loaded same way to see if that is typical. Need to check SD for more five shot groups with these. Due to suggestion or question from here, cases were segregated according to weight. Also discovered that my cases were all close to needing to be trimmed and trimmed them all. More uniformity.

The range trip was one of my best ever. With some of the cases that had the primer pocket uniformed and were trimmed but no flash hole deburr I had a 1" inch group with four of them going into one hole smaller than 1/2", I believe it was the weighing and other things besides the deburring that did this so will do from now on.

Thanks guys.