Bullet run out /concentricity article

http://www.gunnersden.com/index.htm.rifle-reloading-bullet-run-out.html

I have just narrowed down my poor case chamfering technique to getting a few none concentric rounds where the bullet is seated at a very slight angle and (I believe) caused wee fliers in groups. Never really thought about it before, but now I roll all my cartridges on a flat surface to check for run out.

Always something new to learn, eh?

Good article solely aimed at persuading you to part you with your cash!
Chamfering only needs to be enough to break the edge, any more (done with hand tools) will lead to un-uniform chamfer!
 
Funnily enough, I managed to read the (in my lowly opinion) useful article, solve my problem and not part with any cash.

I thought about putting an exclamation mark in at the end for effect, but couldn't be a##ed.
 
Good article solely aimed at persuading you to part you with your cash!
Chamfering only needs to be enough to break the edge, any more (done with hand tools) will lead to un-uniform chamfer!

I agree. If you want bullets seated straight, get BR-grade dies or use a Lee Universal Expanding die to put a gentle flare on the case mouth.~Muir
 
I agree as well (it was the unnecessarily dismissive tone of the reply I didn't like), but my lazy chamfering technique was not even and using a Lee Loader the bullet did not always seat straight regardless of whether using boat tail or flat base. I no longer have my Forster seater as the ex binned it. A borrowed neck thickness guage didn't show any issues with brass, though it was on 4th or 5th loading. I've always done a shallow chamfer, but my technique with the lee chamfer tool wasn't always even. I followed what I do with the .22 Hornet and put a very slight bell into the case mouth with my expander as well as do a proper clean chamfer. That sorted it. Even better were results with a light crimp from Lee factory crimp die that brought ES down to teens and a definite improvement in groups.
Never bothered to look at whether bullets were concentric before as I do far more hunting than range shooting, but got interested in why I was getting the occasional flier when all else was good. So I thought to post my findings on the off chance it helped anyone else.
 
This is what was happening. Good groups and a flier that couldn't be called. It was only when recently emptying a packet of rounds on the kitchen table and rolling them that I could see a handful were definitely out of true. So I took those rounds out and shot them and the grouping was far worse than usual. The rest of the packet grouped really well. I don't think the Lee Loader helped things in combination with my lazy and probably uneven chamfering, but until I can buy a competition type seating die again it will make do.

The 2nd target with 80gr Noslers is 4 rounds plus a flier at 4 o'clock in the black. The old Sako Forester rebarrelled with a PacNor 1:9" always shot this tight - ignoring the flier. It way out shoots my ability on targets.

The last 2 targets are for 105gr GECO factory cartridges. The last batch I bought didn't group nearly as well (lucky to get under 2") as before so I set about playing with seating depth (seated them out further) as advised by many on here and applied a light crimp. I also recharged them with H1000. Both ways worked a treat.

Old hat to many of you, but though I've been shooting and reloading for a long time I've never really played about with it in any huge detail so it's interesting for me to see the results of my own amateurish experiments to sort out problems. Cheers.
 
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Hmmm well I didn't like the look of the Lee chamfer tool so brought the dearer RCBS one and glad I did although I would not buy one now if the last new one I looked at is what their quality has dropped to it was crudly made and very expensive.. Luckily I found where my original one had rolled too :cool:. The RCBS one is longer allowing a better grip and I find it helps alignment. Have not noticed bullet run out using the dies I have and have dies from RCBS, Lee and Redding. I have found a couple of faulty shell holders in the past though. One a Lee #2 was too tight to allow any cases in..

If I suspect a case neck is not uniform I measure using a tube micrometer that I picked up for £2 in a junk shop years ago and putting the case into the Lyman Universal trimmer shows if there is a problem of the neck not being true. Another item I picked up years ago used.

Hand loading is a hobby all of it's own and one can get as deep as one wishes into it.
 
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