How do you eliminate runout

[PNWdude67]

rsmithsr....not .01 but rather .0015. Yes.. the rifle shoots fine. I'm just trying to figure out why I'm inducing this darn runout (.0025) in my reloading process. Not interested in competitive benchrest shooting.
aushunter1.....yes I know it's seems I'm being a bit anal but I have my reasons. I can't shoot those 1/8 moa groups at will and I think the reason is there is something lacking in my reloading process.

Your rifle shoots better than fine and sounds like a sweet rig. Should have never bought that darn run-out gauge, your next barrel won't shoot quite as good and you will have .001 run out in your process. Just kidding Haha! Save some time, form once allowing a moment of "dwell" time at the top of the stroke, get an expander mandrel die and use either an expanding mandrel or turning mandrel which is about .001 difference in neck tension, FL size to at least .002 Shoulder bump, Consider getting a "no-turn" neck chamber on your next barrel. Shooting 1/8 MOA groups "At will" at 800 yards consistently is very ambitious. Environmental inconsistency will fly a shot more times than not. Personally, we have not measured our brass or bullet run out, have never turned a neck. We do all the above mentioned steps along with annealing every cycle before FL sizing. Also use a Fx 120 powder scale and auto trickler to speed up the process and it's accurate as ef. Do all the match loads on a progressive Dillon 550 (two runs) because a batch is 800 pieces. Goal is spend less time loading more time shooting. I load 7 SS and 6.5 SS on Two single stage presses with same steps.

 

[PNWdude67]

Welcome to this rabbit hole I'll give you my personal experience, and you can determine if it will be helpful to you.
One of the best ways to obtain concentricity is by proper seating depth of the bullet. You want the bullet base or base/boat tail junction to be at the brass case neck/ shoulder junction. Besides giving you very little runout, this tends to be a perfect seating depth (I've done a ton of seating depth tests and 9/10 end up being this COAL).
Next is the neck tension issue. Fired brass will need to be annealed usually after 3 firings to keep the neck tension consistent. I use the Redding Type S bushing with the bushing that sets tension to either 0.002 or 0.003. I get perfect tension using the Sinclair Neck Turning Mandrels because they are exactly 0.002. If you want 0.001, then use the Expanding mandrels. I do this on all the virgin brass. Running the mandrels through the necks creates a uniform inside diameter at pushes the "thicker" area of the brass to the outside. You can choose to neck turn to clean up the outsides if you want, but I haven't found any noticeable difference.
I learned this method from Remmy700 on this site. It has dropped my ES and SD numbers.......most are single digit now. When I check run out, it's either 0 or 0.001.
I do own many Lee Collect Neck Dies and they are wonderful.

Solid process and we do the same, the Sinclair mandrel die is a key step imo. Also very nice to have if you drop a case After forming and dent the neck

 

[Patriot007]

You're getting .0002 runout?

All DAY LONG, with the majority of my cases. The gauge on my Neco, is a Gem.0005. Each line on the gauge is .0005.
It makes reading and fine tuning a breeze. I'm sure that's not the answer you were looking for but if you look back through my posts. I'm sure I have already talked about my case prep. It boils down to the tools you use and how you use them. I'm not saying that you need HI dollar tools to make accurate bullets. For instance, I use a Forster co-ax press. My father in law uses a Lee Cast press. We both use about the same every thing else. He is 85 yrs old, I'm 55yrs old. He shoots way better than me. His bullet run out is under .0005. That probably because we both use the same process. The question is, how much time do you want to put into making those rounds and the repeatability of your process .I know it doesn't boil down to the price of your press, so it has to be the process you use to process your brass. I will attach a
photo of a page out of my Neco manual of what acceptable brass is. I know this wasn't the answer you were looking for but it gave me a moment to talk about my Neco. I love this gauge..

 

[Patriot007]

Have you tried other brands of dies? It's no doubt just me, but, I've had lousy luck with Redding dies and runout. Forester has always been good to me. Come to think of it, Lee has treated me better than Redding. Just a thought.

I do have 1 Redding die in my Gun Room. It's their universal decapping die. It works great. The reason I have it is. The decapping pin works with my small primer pocket flash holes in my lapua 6.5 CM Brass. Every thing else is Forster and Lee.

 

[tribb]

Brett.....lot of opinions I see, its really up to you what you want to do with your rifle. I don't shoot benchrest and still want my gun to shoot bugholes, you got the good stuff in equipment and equipment to measure your runout. You asked a simple question, yeah there are those that don't believe or care about runout. I have two guns so far that shoot one's and two's and I can see the difference in their groups with concentric ammo........for sure. Its those slight opening's in groups that you know you didn't pull. The member on here that turned me on to this just built a rifle that shoots under the one's like I wished mine would. Never heard any one complain their gun was too darn accurate

What do you have to loose? lee collet neck die at Midway $24. Sinclair expander mandrel with 30 caliber mandrel $43. at Sinclair's. You got a good rig and desire to shoot better, now its the little stuff that dials you in that final distance.......weighing brass-exact primer seating depth-eliminating runout-perfect powder weight-and sweet spot distance off lands. You know what I'm talking about. Heck I'm getting old and can tell I'm losing the fine accuracy edge I had thru life some, but you never stop learning and you never stop getting that rush when you have a good day and the groups are near perfection Good Shooting

Amen to that brother

 

[JWM]

In an effort to improve my reloading process with the intended goal of improving accuracy, SD and ES I have invested in a concentricity gauge to measure runout on my brass necks and finished loads. I also just started using a Redding type S full length "bushing" sizing die to control neck tension. For some darn reason all of my brass necks are ending up with about .0015"-.0025" of runout. What am I doing wrong?

Forster dies are the simple answer

 

[nicholasjohn]

Trying to make perfect ammo can drive you crazy. Some have touched on it but your press can induce runout no matter how much you spend on precision dies. If the ram, or even the shell holder isn't perfectly square and centered on the die it will induce runout. I'm using my rockchucker press I bought new in 1981. All that wear and abrasive powder residue have made the ram extremely sloppy. I believe that play makes better ammo. The coax presses have floating shell holders. slop helps the brass center itself in the die. the Lee collet dies have some built in slop and are also self centering.

Some guys put an O-ring under the die locking ring before screwing it into the press, and/or on the sizing or seating stem before screwing it into the die to induce a little free play between hard metal parts. Forster used to put black rubber washers in their dies for this purpose - don't know if they still do that, but it makes for a floating effect in the sizing button's assembly which is said to let things center themselves on the case rather than having it all centered in the die. Also, the dies in Forster's Co-Ax press all wobble a little bit, rather than fitting tightly in the press. The same concept is at work with this set-up.

 

[kiwikid]

In an effort to improve my reloading process with the intended goal of improving accuracy, SD and ES I have invested in a concentricity gauge to measure runout on my brass necks and finished loads. I also just started using a Redding type S full length "bushing" sizing die to control neck tension. For some darn reason all of my brass necks are ending up with about .0015"-.0025" of runout. What am I doing wrong?

Hi Brett, how many thou OD difference between your fired cases and your sized cases?

I had a similar issue with a 6.5x55mm load using Redding neck bushing dies. The fired cases measure .299" and I have to size them down to .291" to get .002" of neck tension. My fired case have <.001" of run out but after resizing this has increased to .002-.003".
Redding suggest that if the necks have to be reduced by more than .005" then it should be done in steps. In my case I bought a .295" bush and run all the cases through that first and then swap for the .291" bush and run them through again.
By doing it in two steps my run out has stayed at the <.001" that they came out of the rifle with.

 

[doggonner]

with .0015 runout, even so a carbon ring can triple that runout, shove the brass against the nk wall and push the bullet around, that being a bad buildup, checkout FClass John on utube top shooter in Fclass

 

[dougduey]

Your rifle shoots better than fine and sounds like a sweet rig. Should have never bought that darn run-out gauge, your next barrel won't shoot quite as good and you will have .001 run out in your process. Just kidding Haha! Save some time, form once allowing a moment of "dwell" time at the top of the stroke, get an expander mandrel die and use either an expanding mandrel or turning mandrel which is about .001 difference in neck tension, FL size to at least .002 Shoulder bump, Consider getting a "no-turn" neck chamber on your next barrel. Shooting 1/8 MOA groups "At will" at 800 yards consistently is very ambitious. Environmental inconsistency will fly a shot more times than not. Personally, we have not measured our brass or bullet run out, have never turned a neck. We do all the above mentioned steps along with annealing every cycle before FL sizing. Also use a Fx 120 powder scale and auto trickler to speed up the process and it's accurate as ef. Do all the match loads on a progressive Dillon 550 (two runs) because a batch is 800 pieces. Goal is spend less time loading more time shooting. I load 7 SS and 6.5 SS on Two single stage presses with same steps.

The Fx120 scale/trickler is amazing and takes your reloading time another level of precision. I didn't know there was a sweet spot inside the sweet spot until I could measure a charge to the kernel of powder. My ES and SD's are so good now. Obtained an ES of 3 and SD of 0 for a 280 AI load!!

 

[Arkansasdad]

In an effort to improve my reloading process with the intended goal of improving accuracy, SD and ES I have invested in a concentricity gauge to measure runout on my brass necks and finished loads. I also just started using a Redding type S full length "bushing" sizing die to control neck tension. For some darn reason all of my brass necks are ending up with about .0015"-.0025" of runout. What am I doing wrong?

Start checking the TIR at the base of the cartridge as close to the chuck as possible and move forward in small increments, you may find it is the chuck giving you a secondary axis. Brass base will not be totally perpendicular to the body, remember we are dealing with an annulus and it can never be an exact plane. All arrows, pipes, gun barrels, or anything hollow cannot be truly straight. Bullet center may be more tolerant of axial run-out since the center of gravity is displaced less than the outer dimension reads.

 

[Brett Bracken]

Sorry to take so long to get back to this....wow...a lot of new responses since I last checked.. please forgive me if I don't address each and every one of you individually. Suffice it to say that I appreciate everyone's thoughts, comments and advice.
I think I'm using quality reloading equipment: Forster co-ax press, 21st Century concentricity gauge, Forster dies, Redding bushing dies yada yada yada. I've also ordered, on the advice of Savage and a few others, a Sinclair expander mandrel and a Lee collet die for 300 WM. When those come in I will give them a try. Taking JE Custom's advice I will then go through the whole process, measuring at every step to see if I can identify the problem that's causing so much run-out in my reloads. Is it all worth it realistically....I don't know. But some paths, even though they may be dead ends, must be followed to the end for our own edification. All I want to do is load the best round possible.

 

[Brett Bracken]

Start checking the TIR at the base of the cartridge as close to the chuck as possible and move forward in small increments, you may find it is the chuck giving you a secondary axis. Brass base will not be totally perpendicular to the body, remember we are dealing with an annulus and it can never be an exact plane. All arrows, pipes, gun barrels, or anything hollow cannot be truly straight. Bullet center may be more tolerant of axial run-out since the center of gravity is displaced less than the outer dimension reads.

What is TIR???

 

[25WSM]

Run-out on your loaded cartridges is one of the things that effect accuacy the least. If you keep it .003 or less you are good. .001 doesn't shoot any better. Powder charge and seating depth and neck tension are all vastly more important. I have experimented with clocking my cartridges and shooting at 1000 yards and don't do that anymore either. I have purposely bent the bullet in the neck and tested groups and up to about .015 run-out couldn't tell a difference at 100 yards. I did some .050 run-out and my groups did open up to about 1/2 in. This gun I did the test in shoots 1s and 2s consistently. .015 run-out still shot in the 2s. Do the test yourself and you won't worry about run-out anymore. To get the run-out big I bent them in the Hornady run-out guage.
Shep