Concentricity - setting up dies - runout

[Bart B]

Bart, what you supposedly correct with FL sizing, would be factors of fantasy, -if not for your FL sizing.. Your rationale put's a carriage before horses, and your method is self perpetuating to this rationale.

If my method's putting a carriage before the horse, so be it. The smallest 10+ shot long range groups I know of have all been shot with cases so sized. I'm not aware of any die use and set up that's produced better results. If there is, please, anybody, let me know. As far as I'm concerned, it's reality, not fantasy.

 

[Mikecr]

I'm not aware of any die use and set up that's produced better results

And I'm not aware that other die use has produced any worse results, if the context of your position is target shooting 'results'.
People shoot 'good enough' either way.

But if the 'results' you refer to relate in some way to the subject at hand, then I contend that FL sizing does not produce straighter ammo.
In fact, it's the very largest of all contributors to runout.

I here what you're sayin; It don't matter, just take shortcuts,, I shoot good enough with them..
But it's more belief than basis, unless you can provide a rational argument that straight ammo in tighter chambers won't perform as well or better.

 

[TnTom]

It takes a little more time and effort up front to build a round that has no variation in axial relationships than it does to build one that is slightly misaligned. I'll opt for the former.

A little more time up front seems to yield more trigger time overall and I do know for certain I don't tie up much time measuring anymore, simple random sampling. It goes along with making your process work for you what ever it might be. I enjoy measuring but I enjoy shooting a whole lot more.

Less than .001" is as straight forward as less than .003".

 

[Bart B]

But if the 'results' you refer to relate in some way to the subject at hand, then I contend that FL sizing does not produce straighter ammo.
In fact, it's the very largest of all contributors to runout.

I've tried every "good" neck sizing die on .308 and 30 caliber magnum rounds; nothing shot as accurate as full length sizing dies with lapped out necks. One exception; the magnum cases get double sized; second sizing uses the middle part of a full length die to size the body totally down to just barely touching the belt eliminating the ridge that usually builds up there.

I get better accuracy with new cases than any form of neck only sizing. And in SAAMI spec chambers, too. This will no doubt get a few folks riled up, but it's true. OK, fine; so I don't know how to neck size a case with Neil Jones' bushing dies.

After discussing this full vs neck issue several times with Sierra's former ballistics manager and others who've shot test groups smaller than benchrest records, I finally decided to go ahead and full length size all my cases. They do so with their reloaded cases used to test their bullets. Nobody shoots 'em as accurate as they do from their SAAMI spec'd chambered test barrels.

Whatever one needs to do to get best accuracy should do it.

 

[boomtube]

Bart, your #24 post has the most lucid - and correct - explaination of how a case fits in any chamber during firing I've ever seen on the web, including a couple of my own efforts. I tend to neck size my target/varmint ammo but, strong ndividual opinions aside, most of us who have honestly tried both neck sizing and FL sizing know that it rarely matters if each is correctly done.

I disagree with your accessment of the effect on OAL of an O ring under a die vs. simply screwed down tho. Once the slack in the mating threads is taken out, the ram/seating force is taken directly by steel to steel contact. It doesn't matter how that gets accomplished, an O ring/springly washer under the lock nut pushes the die treads up as surely as the lock nut can by itself.

 

[Trickymissfit]

Bart, your #24 post has the most lucid - and correct - explaination of how a case fits in any chamber during firing I've ever seen on the web, including a couple of my own efforts. I tend to neck size my target/varmint ammo but, strong ndividual opinions aside, most of us who have honestly tried both neck sizing and FL sizing know that it rarely matters if each is correctly done.

I disagree with your accessment of the effect on OAL of an O ring under a die vs. simply screwed down tho. Once the slack in the mating threads is taken out, the ram/seating force is taken directly by steel to steel contact. It doesn't matter how that gets accomplished, an O ring/springly washer under the lock nut pushes the die treads up as surely as the lock nut can by itself.

good post.
gary

 

[Mikecr]

Ok Bart, it's obvious you are comfortable shooting FL sized brass.
But that's not at all what this discussion is about!
Look at the heading for this thread. Was the question posed whether crooked ammo shoots as well as straight ammo?
I think not. We're talking about reducing runout, and NOT shooting regardless of it.

You should start a new thread, where you can ascert your supreme shooting achievements while embracing every shortcut known to man. That would be good reading -somewhere else.

 

[dig]

Tried the "O" ring trick today on the Turret Press. I dont have the guage yet to measure but getting the expander in was easier and also easier on the seating die without hitting. I also used a smal "O" ring on the die inserts. It worked better. For me a worthwhile trick if just for better alignment.

Thanks all,

 

[rscott5028]

The Hornady concentricity gauge is junk.

I already owned the NECO, but I bought the Hornady because of the marketing hype about correcting concentricity. Plus I like gadgets.

(1) it rarely detects as much as .005" TIR as identified by the NECO

(2) bending necks to get a smaller reading doesn't equate to straighter ammo or better groups

(3) I thought the "slop" built into the one I got might be a fluke. But, I've since handled 2 others and it's just poor quality/design.

Do yourself a favor and get a setup with a dual v-block design and improve your process/tools/components to avoid runout.

Hope this helps.
Richard

 

[sp6x6]

I have the Sinclair, does that look like a good design, seems good.

 

[rscott5028]

I have the Sinclair, does that look like a good design, seems good.

I haven't used the Sinclair. But, they make great products. It may be better than the Neco. Although, the Neco can do a lot of things.

 

[Trickymissfit]

I haven't used the Sinclair. But, they make great products. It may be better than the Neco. Although, the Neco can do a lot of things.

The NECO will be better just from the dial indicator alone. I do suppose that you could use a digital read out indicator with the Sinclair to fix that problem. Pendel had a couple that I thought were the very best I've ever seen! I have a design that I think is slightly better than the NECO, but on the otherhand the NECO will actually do more different things.
gary

 

[boomtube]

The choice between NECO and Sinclair is not simply 'which is best.' NECO's case device is very costly but it's a mutifunction tool; one function is concentricity. Sinclair's concentricity gage is a single function tool that does what it does as well as can be done and at a rational cost. Anyone wanting/needing the functions the NECO unit provides will do well to get one, if they don't then the Sinclair is a much more cost effective tool and that's the extent of it.

 

[Trickymissfit]

The choice between NECO and Sinclair is not simply 'which is best.' NECO's case device is very costly but it's a mutifunction tool; one function is concentricity. Sinclair's concentricity gage is a single function tool that does what it does as well as can be done and at a rational cost. Anyone wanting/needing the functions the NECO unit provides will do well to get one, if they don't then the Sinclair is a much more cost effective tool and that's the extent of it.

be the first to admit your right. Yet the NECO is probably a little more accurate due to the indicator setup alone. By the time you got a good indicator with the Sinclair, you would still be a lot of money ahead with the NECO. But none are perfect
gary