Concentricity

[gzig5]

Larry,

I'll check the runout of my ammo and if it is OK, I'll send you my seater to see what your results are. Give me a day or two to do the checks. I need to find my NECO concentricity gauge somewhere in the cyclone's path. Mine are older RCBS dies but you've seen the results out of that little Sako. In the meantime, do a little design of experiments (DOE) and mark the high side of the bad rounds and then shoot groups with them indexed to the same clock position in the chamber. Curious what your result would be.

Greg

[gzig5]

Good news, the NECO was in the first place I looked. I measured five random rounds from a box I brought back from this spring. Remember I am running turned necks. Anvils are set up just in front of the solid case head and halfway up the neck. The indicator is ~1/8" in front of the neck. The worst of the five was less than 0.001". I found out why when I opened the die box. Sometime in the last two years I bought a Forster Micrometer seating die. I'm sure it was used because I'm too cheap to buy new. Sad thing is I don't remember why or when, but it apparently works pretty well. In the name of science, I changed my anvil setup to what George has pictured, with the v-blocks in front of the web and just before the shoulder angle starts and the runout doubled to about 1-2 thousandths depending on the sample. Don't know which method is more right but that isn't the point. I'll give you a call and then send it to you this week. If you want to turn necks I'll send you my gizmo so you can turn 2-3 per minute on the lathe. It beats watching network TV.

Edit to add:
I went back and set the indicator on the case neck as in George's picture and got essentially the same .002" run-out as out on the bullet, so the seater seams to be doing it's job.

[gzig5]

Originally Posted by Harold M

Front "V" is on the SHOULDER, not the neck, right?

Harold

I did it both ways but yes the last go round was supporting the shoulder with the indicator out on the bullet. Gave same reading as when supporting the shoulder with the indicator on the neck. To me that means most of the runout on that round is in the brass, not the bullet/neck alignment.

[Lenard]

I shoot a 20 TAC (2) and a 223. I battled runout for quite a while, and solved the problem for me.

I found that the stem in FL dies get bent very easily So, I run the stem way up in the die to FL size the case. Next, I run that case thru a Lee neck sizer. The neck sizer seems to straighten up the necks. I might add, I turn all necks using LC brass. I have gone from.002-.003 of runout to only a half thouisands. Consequently, the group size when I am doing my part, is almost always under a quarter inch and many in the .100-.200 range Occasionally, I will get a flier from a case that seems like the others, so when that happens, I pitch the case.

I am sure other methods work just as well.

[L Rivard]

Gzig, hold up on sending anything out, I've got myself talked into the Wilson seater, so it will take me a while to try that route. I don't think that is likely to fail to solve my problem, but if it does I,ll give you a call. Thanks for the offer and thanks to all for the advice.

[L Rivard]

Thought I would give you folks the rest of the story. Received a Wilson Seater closely followed by a couple of boxes of Lapua brass. Seating Speer 52 grain FBHP bullets I got the following results; Lapua brass gave .000" to .002" T.I.R. on the bullet, most individuals showing just a wiggle on the indicator. Some several times fired Nosler ran .000" to .003", with most individuals about .002". Some many times fired Winchester ran up to .005" All brass was .002" or less out of the Full length resize dies. Using the Wilson die I can now proceed with load development .

[georgeld]

Just a short note of correction.
Gzig: That was Harold that posted the picture not me.
Don't make much difference though, shucks, I'd be glad to take the
credit but, I don't play these games with ammo.

L.Rivard: So, how do they shoot now??

[L Rivard]

I've only had the die a few days and the weather has been pretty crappy, but with about 50 rounds down range it looks like flyers are much reduced. Really too early to tell, still trying different bullets and powders. The rifle involved is a Martini Cadet, so I don't expect to get into benchrest competition territory, but most five shot groups are about tree quarters of an inch with three of the five in the .03" area. This rifle is used on ground squirrels so is in the usable range already, but it's fun to see how well it can be made to shoot.

[georgeld]

just a suggestion from my ONCE experience.
Settle on a load, use it for ALL your bullets within
the wt range possible. Sort the bullets first.

Then tinker with powder, and maybe primers later.

When I had my Sako L461 rebarreled, two of us came up with
19 bullets between 35 and 55gr. I had the load from when it was
222mag. Stuck with it: 25gr 4895, CCI.

Five shots of each bullet sorted them out to ten. Ten loads of each proved 35 & 40 gr V/max and 55gr C/L were by far the best. Third round, confirmed it. The 40gr V'm's made ten holes .230", the 55's just barely under half inch.

I shoot the light one's around livestock and places I can't have any ricochets, the 55s are my general prairie dog loads. They will exit and destroy a coyote hide. The lighter v'max's don't, so those are used for furs too. The 35gr are only good out to 200yds then they scatter all over the hillside, once those were gone I've stuck to the 40's.

Best wishes in getting things sorted out soon. Work on ONE item at a time and skip the head scratching games, it's much easier this way.