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concentricity issues

Posted: Sun Apr 10, 2011 4:39 pm
by bigcatdaddy
Some questions please. I am attempting to move from a reloader, to a more accurate handloader. For those of you who do check neck runout and neck thickness, do you turn and ream necks? Or just toss the rejects?

And once you are satisfied your necks are perfect, do you still check bullet runout? Or just assume they're acceptable? If you do check bullet runout and have rejects....do you scrap and dismantle, or try to straighten them on something like a Hornady concentricity guage that has a "straightener"?

I have the Redding concentricity guage. Can this rig be converted to check bullet runout? Is there a way to correct bullet runout without buying another guage setup?

Or perhaps this is all overkill?

Thx for the answers.

Re: concentricity issues

Posted: Sun Apr 10, 2011 10:54 pm
by chris_32212
I am not qualified to answer these questions for you but I am very interested to hear from some folks that might be. I bought the RCBS case master gauge that checks neck thickness and concentricty/runout(it is still being shipped to me). I also bought a good dvd called "Advanced Handloading Beyond the basics" and they recommend not turning the neck because its not worth the time and effort. They say to use the pieces that are out of spec for non precision shooting like fouling the barrel slightly after cleaning, before target shooting for accuracy.

Re: concentricity issues

Posted: Sun Apr 10, 2011 11:06 pm
by bigcatdaddy
I like the Youtube vids of that RCBS guage Chris. Interesting, the Redding instructions also said to toss the rejects or set aside for less demanding uses....but dang, I sure see alot of neck-turning going on out there.

I bought the high-end Redding micrometer/seater for my 7mm-08 accuracy Frankenrifle rig, supposedly to give better seating alignment. What I'm really after is the .204. Yup, only shooting max out to 300-400 yds, so many say "waste of time"...but my target is a prairedoggy. Aweful small target with the fur off.

Re: concentricity issues

Posted: Mon Apr 11, 2011 9:40 am
by bow shot
I've chased the concentricity thing around the map and and am now producing >/= .001" TIR on my 204 rounds (on the case neck and on the case-side of the bullet olgive).

Having bought the gear, fiddled, fussed and obsessed, I can't say that I've gained accuracy (I'm shooting 0.3" 5 shot groups) BECAUSE of the concentricity gain, but it is nice to squeeze off a round, have it go "bad" and say "I KNOW this: its NOT a concentricity issue". I'm shooting a "factory" weapon, Savage 12 VLP.

I'd much rather buy good brass (Nosler for me), neck-size (Lee for me) and use a good seater (I use Wilson) than re-manufacture cheaper brass. But that's me, some folks prefer to work their brass, I find it less expensive in time and money to just buy good stuff.

Really, really put the search tools here to work, there is a ton of great info, and you'll get to it faster than waiting for replies. Aslo, check out the forums at TheFiringLine.com.

Re: concentricity issues

Posted: Mon Apr 11, 2011 10:12 am
by bow shot
And to actually ANSWER you questions, LOL...

1) I only outside turn the necks.
2) Once I'm satisfied that necks are perfect, I still measure the TIR of the cartridges. If a shot doesn's hit the mark I want to be sure the the problem was ME, not my load.
3) If I have bad TIR on a cartridge, I use it is as a plinker, and then fix it the brass (in the manner given below).

Before I bought good brass: here's what Id did:

1) Measure concentricity of fired brass with a runout gauge and record (usually close to .002", that stage its a mirror of the chamber!)
2) Neck-size (Lee) re-measure, record... (here's where the TIR variation manifests).
3) Outside neck turn (Forster) a tiny bit if TIR is "not good", re-measure, and record.
4) Seat (Wilson), re-measure TIR, record, and shoot.
5) repeat 1-4 until TIR is </= .001"

(I rarely have to trim length after the 1st firing.)

The reasons I don't do this anymore, and just buy good brass:
1) Inconsisent neck wall thickness is THE reason for bad TIR. If the NECK thickness is not without variation, neither is the REST of the case. That manifests as inconsistent VOLUME, case-to-case...which is like the reverse of varying powder charge case-to-case.
2) It takes a lot of time to work the brass.
3) I had to buy a bunch of measuring/working stuff to work the brass.
4) I could DEMONSTRATE that using brass having consistent volume case-to-case improved my accuracy, and good TIR "came with it" so to speak.
5) I could get the inconsistent brass to have good TIR, but it still had poor accuracy.

Re: concentricity issues

Posted: Mon Apr 11, 2011 11:25 am
by bigcatdaddy
Bow Shot!
Exactly what I was looking for. Thx for sharing what you do. Remember when you were where I am?..."I wonder if I should chase this concentricity issue"?

Yes, there is plenty to read on a "search"...problem is, it's not consistant advice. This has led me to believe I must try it myself and see. So I've decided to invest in a quality sizer and seater and neck thickness guage, and Hornady neck turner....but you can take this thing to no end of minutia. And for what return? I like that you agree with RCBS and Redding, that implied case imperfections make rejects a no-go for accuracy work.

I wonder if I'll be still chasing this issue a year from now?

Re: concentricity issues

Posted: Mon Apr 11, 2011 11:55 am
by bow shot
Understood, 'Cat!

Enjoy the trip!

Re: concentricity issues

Posted: Mon Apr 11, 2011 6:42 pm
by chris_32212
please keep us posted on your progress and let us know what you find out.

Re: concentricity issues

Posted: Mon Apr 11, 2011 9:10 pm
by Jim White
I've discovered that;

-TIR can also be caused by sub-par or worn reloading equipment, especially bent (however slight) decapping pins and worn reloading presses.

-Inconsistet case neck thickness will make you scratch your head when you can't put a good group together @ 200 yards.

I have neck turned but I have never reamed cases.

HTH...

Re: concentricity issues

Posted: Sat Apr 16, 2011 7:17 am
by bow shot
'Never thought of that Jim, excellent post.

Re: concentricity issues

Posted: Sat Apr 16, 2011 7:26 am
by bigcatdaddy
Jim
could you share what you do in re: to the OP questions?

Re: concentricity issues

Posted: Wed Apr 20, 2011 6:39 pm
by Jim White
bigcatdaddy wrote:Jim
could you share what you do in re: to the OP questions?
I'll give it a shot.

Some questions please. I am attempting to move from a reloader, to a more accurate handloader. For those of you who do check neck runout and neck thickness, do you turn and ream necks? Or just toss the rejects?

I do turn necks. My goals is to remove just enough to make the neck concentric and uniform through out the LOT.

And once you are satisfied your necks are perfect, do you still check bullet runout? Or just assume they're acceptable?

Ahh-haa...one of the rules of life is; "Thou shalt never assume". IME, once the culprit for run out is found and corrected it's generally good to go and I'll spot check after that.

If you do check bullet runout and have rejects....do you scrap and dismantle, or try to straighten them on something like a Hornady concentricity guage that has a "straightener"?

If they are really bad I'll set them aside and shoot them. When I get home I'll check the brass for run-out and in my case, it's always been corrected. At that point I'll resize it and recheck. If it's bad again, then you need to look at your reloading equipment. Thats how I discovered my reloading press was bad.

I have the Redding concentricity guage. Can this rig be converted to check bullet runout? Is there a way to correct bullet runout without buying another guage setup?

I use a RCBS Case Master and I can do case, ammo and bullet run-out on mine. I'm not familiar with the Redding unit myself.

HTH

Re: concentricity issues

Posted: Sun Apr 24, 2011 2:39 am
by Wrangler John
Gee, there must be something wrong with me. I don't measure runout, or concentricity at all. Couldn't care less about it. I measure a random batch of necks for thickness, and even Winchester comes in around .001" to .0015". That's nothing to worry about, or hassle neck turning over. My little 15 lb Savage rifle with the.204 Ruger Shilen Select Match or PacNor Super Match barrel shoots between .240" to .30" groups (with a 26 grain Varmint Grenade no less). Just size them with neck bushing die and load away, even on a progressive press. Back in the day, I shot hundreds of handgun metallic silhouette matches with runout around .0015" in 7mm TCU Contenders, or the 7mm International Wichita bolt pistol and my own handmade jacketed 120 grain bullets. Managed to keep them all on 4" diameter "turkey eggs" at 200 meters with open sights. And that on a 20 year old RCBS Rockchucker with standard old dies.

In benchrest shooting for iddy-bitty groups it may make a difference, but in practical shooting for score or splats, it's far less important. My last rat shoot saw the critters pile up like cord wood out to 250 yards - that rifle is truly amazing, the .204 Ruger is amazing. I'm sure glad the folks at Ruger came up with this superb cartridge. As for runout, runout and buy one.

Re: concentricity issues

Posted: Sun Apr 24, 2011 8:55 pm
by Jim White
Wrangler John wrote:Gee, there must be something wrong with me. I don't measure runout, or concentricity at all. Couldn't care less about it.
I used to be that way too until I ran into a problem and discovered that hardware does go south, hince my 25 year old single-stage press. For, me a 204 Ruger is a waste at shooting ground squirrels 200 yards and less, unless it is very windy with full value. I have 17 HMR's and 22LR for that. For me, I'm not afaraid to take shots at 400, 500 or 600 yards with any of my 204's at those pesky little ground squirrels and it is a challenge that far out.

For consistent knot-hole groups @ 200 yards, all that stuff helps and besides, you only have to prep the brass just once.

HTH,

Re: concentricity issues

Posted: Mon Apr 25, 2011 7:47 am
by Rick in Oregon
Wrangler John wrote:Gee, there must be something wrong with me. I don't measure runout, or concentricity at all. Couldn't care less about it.
Wrangler: At one time, I felt the same way until I found accurate rifles not grouping all that well. The problem was traced to my old Rockchucker press, circa 1968. I had just plain worn it out. It was giving me TIR in the neighborhood of .006", and when I replaced it with a Redding Ultra-Mag (overkill, I know) and Redding Comp dies, my runout problem went away, and all my smallbore rifles went back to shooting bugholes.

I have respect for your knowledge and experience, but if you expect to hit a ground squirrel at 600 yards with a 204 or similar cartridge, having a minimum of runout is critical, belive me, as with .006" TIR, you're only throwing lead at the rats at that range, not hitting them. Been there. :?

Jim: Agree completely.....faulty/worn-out hardware made a believer out of me too. :D