Thread: Fixing Run-out

4 Thou runout is pretty good for standard die sets but 5.5 - 6 thou for the sierra's is not so good, they look like quite a pointy bullet so I am betting that the seating steam does not match the bullet.
I have not checked myself as I am not a good enough shooter and my rifle is not up to it, however it has been said that 3 thou (0.076mm) is what is required to get down to 1/2moa providing the rifle and shooter are up to it.
This takes a pretty fancy die and press setup s well as top quality and sorted brass.

4 thou RO I would not be happy with but it will most likely not be the cause of your accuracy issues, as pointed out back a bit.

I first became very anal about runout when I used to shoot Fullbore.
It seemed to be a random cartridge to cartridge thing as I loaded them (yes I partially seat the projectiles and the turn 180 degrees and complete, always have).

(When I first started handloading, again for fullbore, I rolled the cartridges across the top of my loading desk. If they didn't visibly go madly up and down at the tips they were deemed vg.)

So in a batch of say 30 loaded I would have maybe 6 that I deemed to have excessive runout. (And some of these had greater than 4 thou runout.)
These I would put aside for the easier ranges eg 500 yds.
Eventually I would end up with so many that you have to either strip them and reprocess them or fire them.
I then used to fire them on club days at whatever range was being shot.
And....my possibles still kept coming in and without reduced centre count.

I'm not trying to say runout control is not important, it is. A projectile starting of on the piss into the bore never corrects itself.
It's just that runout is part of the whole package. I would rate neck tension as important if not more so than minor runout.

To get to the bottom of runout you need to examine your cases at every stage of the process to find where the issue is being induced.
Using your runout gauge measure the necks as they come out fired from the rifle. You should see maybe 1/2 to zero (preferable) thou runout.
Check at each stage of your reloading ie after neck sizing or FLSing (which ever you do) and so on.

Final check before seating. If possible run a gauge inside the necks as well as outside. If you detect runout at this point I have found no seating die will correct it.
(I have Redding Comp, Wilson inline, Forster Micrometer BR seaters.)

I haven't mentioned the basics here like good neck chamfering etc.

The biggest causes I have found to be Redding Body dies (necks totally unsupported), some bushes in bushing dies, just plain poor quality dies in general.

The humble much maligned, by some, Lee Collet die I have found to be very good at keeping necks straight. Again straight necks going into a good seating die will usually give straight cartridges out.

I have completely changed my loading process. I now anneal after every firing, FLS (Forster die with expander removed, 0.5 to 1 thou shoulder bump), then expand necks using expander mandrels to generally give 2 thou neck tension.
I get zero to 1 thou runout measured at the projectile tip. I could never consistently achieve this with bushing dies.

As pointed out by winaa, quality seating stems are important. My seating stems are honed to give good contact on the projectiles. Unfortunately it means I have ended up with multiple seating stems. VLD stems for VLD projectiles etc.

Now, having said all that above, I just load my 223 with standard dies and it shoots tiny wee groups.

Yes I have VLD seating stems in my dies (223 and 6mm)

The thing thats really bugging me about this . . . my 223 target rifle was also shooting poorly with 80 gn Sierra's aka long snooty buggers too. With the new press and careful monitoring of my reloading process, its now shooting well again - holding 1/2 MOA out to 500Y

I've tried both 110 Sierra's and 108 Hornady's (and will also try some "hunting" style loads on Tuesday evening), and both shot well when someone else did the reloading (albeit with a different powder H100-V). I could change powder (from 2209) but it shouldn't make that much difference in a well set up rifle.

Originally Posted by Tentman

Yes I have VLD seating stems in my dies (223 and 6mm)


I've tried both 110 Sierra's and 108 Hornady's (and will also try some "hunting" style loads on Tuesday evening), and both shot well when someone else did the reloading (albeit with a different powder H100-V). I could change powder (from 2209) but it shouldn't make that much difference in a well set up rifle.

Thats your answer right there.

Originally Posted by Tentman

Yes I have VLD seating stems in my dies (223 and 6mm)

The thing thats really bugging me about this . . . my 223 target rifle was also shooting poorly with 80 gn Sierra's aka long snooty buggers too. With the new press and careful monitoring of my reloading process, its now shooting well again - holding 1/2 MOA out to 500Y

I've tried both 110 Sierra's and 108 Hornady's (and will also try some "hunting" style loads on Tuesday evening), and both shot well when someone else did the reloading (albeit with a different powder H100-V). I could change powder (from 2209) but it shouldn't make that much difference in a well set up rifle.

Did you check the run out on the loads that someone else loaded for you?
If they are around the same as yours then run out is not your problem. As stated in other replies its more likely you are not sitting on a node.

Tentman +
I could change powder (from 2209) but it shouldn't make that much difference in a well set up rifle.

I would differ on that! As it can come down to powder, especially when you're trying to tighten the group.
But hay iam just a new fellow on the block, I did chase this once and realised it was a rabbit hole and I realised I wasn't going to be the next nz champ.
So I settled for minute of dear and minute of small game and lived happy ever after.
You know I find a load and stay with it and powder helps in the sweet spot.
Patience and perseverance on the Rabbit Hole, hahaha.
KH

I would suggest that you try some of the other 6mm projectiles you have for run out and grouping, if a projectile won't shoot in a rifle its a bloody hard argument to convince if otherwise.

both shot well when someone else did the reloading

Get "someone else" to do your loading, and spend your time shooting.

Win/win.

So tonight we tried some different things, it was a bit beyond my control (gunshop being obliging and tying things). Changed projectile to Sierra 100 gn TGK's and powder to Stabil 6.5. All loads done by gunshop, some on my dies, some on theirs, brass the same, some of mine, some of theirs (but not mixed)

Tried a load that shoots lights out in an identically chambered rifle. Shot one 14mm 3 shot group but nothing else duplicated it, the other group of identical charge weight being 40mm. The other 3 groups of a variety of charge weights being 30 -40 mm.

The fact that the results are so random leads me to thinking maybe its something mechanical and I'm wondering if it could be ignition (the rifle is in a chassis that another action will shoot bugholes from, and I'm using a torque screwdriver). When I disassembled the bolt some time ago I did notice the mainspring was " bound" and didn't look happy - thoughts on this sort of problem being a cause of accuracy issues??

Certainly sounds something is not going together properly, return it to where ever it came from and start anew.

I would contact Targex and get a sampler of at least 20x 70gn flat based projectiles. I have a .243 that refused everything i could think of, but that bullet makes tiny groups no matter what configuration. Its down to barrel twist i guess