Neck sizing causing runout.

dave300

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  • Feb 27, 2013
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    Las Vegas, Nevada
    I have a couple factory Remington Senderos in 300 RUM that I am building some loads for. The fired necks on both of the senderos measure .344, likewise the loaded round neck measures .337.
    What I am finding that happens is this;
    2X fired, Remington brass, decapped, tumbled and annealed.
    The neck on the fired brass starts with less that a half of thou runout. After running it thru the Redding T7 with Redding Competition dies, and using a .335 neck bushing, my runout on the neck is .007-.009!
    I have the die set so there is a bit of play in the neck bushing, avoiding it being clamped down, free floating the neck bushing if you will. The depth of the neck bushing leaves an area above the junction of the shoulder/neck of about 1/16-3/32 that is not neck sized.
    I have went thru and cleaned the die, sleeve and neck bushing. No help. At this point Im convinced it is not the press as I load for several other customs and no such problem, though no big spread between fired and loaded rounds.
    Here is question because I have never loaded for a factory chamber with such a wide variation between the fired neck compared to the loaded neck. Any thoughts that I am taking to big of jump/difference in bushing size and causing some abnormal "shock" to the brass?
    Currently I dont have the bushings on hand to try stepping the neck down, but they are just now ordered.
    I have also turned the brass 1/3 turn increments and sent the brass thru the press on each turn, and that has made a bit of improvement, .005ish on runout.
    Thoughts/Help on cause? I am sure hoping some of the wildcat reloaders can tell me their thoughts, especially since I have a 7/300 finishing up at the smith soon, and Id like input on what size steps are most effective when such big tolerances are encountered. Thanks, Dave
     
    I don't know about the runout problem your having, but I can tell you that reducing the diameter from 0.344 with a bushing of 0.335 will result in the neck being a smaller diameter than you would like. I learned this myself when I first used a bushing neck sizing die. Measure the neck diameter and let us know what it's ending up at.
     
    I have an a simliar result from time to time and have come to learn to "sneak" up on the desired result, but never hasve I had it cause the runout Im experiencing.
    Anyone? Help?
    Thanks

    I don't know about the runout problem your having, but I can tell you that reducing the diameter from 0.344 with a bushing of 0.335 will result in the neck being a smaller diameter than you would like. I learned this myself when I first used a bushing neck sizing die. Measure the neck diameter and let us know what it's ending up at.
     
    I have a couple factory Remington Senderos in 300 RUM that I am building some loads for. The fired necks on both of the senderos measure .344, likewise the loaded round neck measures .337.
    What I am finding that happens is this;
    2X fired, Remington brass, decapped, tumbled and annealed.
    The neck on the fired brass starts with less that a half of thou runout. After running it thru the Redding T7 with Redding Competition dies, and using a .335 neck bushing, my runout on the neck is .007-.009!

    The step is too big. My gun has a 0.3345 obturated neck diameter. I size it in 2 steps with a 0.338 and a 0.332 in a second sizing and get 0.0015 typical runout.
    {Now, technically, I am even pushing my luck as you should neck down only 0.005 per step while I am getting away with 0.006.}

    I have the die set so there is a bit of play in the neck bushing, avoiding it being clamped down, free floating the neck bushing if you will. The depth of the neck bushing leaves an area above the junction of the shoulder/neck of about 1/16-3/32 that is not neck sized.

    I disassemble my Redding competition sizer and clean and lube the sliding sleeve before each session. I also lube the cases even though I am using TiN sizing dies.

    I have went thru and cleaned the die, sleeve and neck bushing. No help. At this point Im convinced it is not the press as I load for several other customs and no such problem, though no big spread between fired and loaded rounds.
    Here is question because I have never loaded for a factory chamber with such a wide variation between the fired neck compared to the loaded neck. Any thoughts that I am taking to big of jump/difference in bushing size and causing some abnormal "shock" to the brass?

    Steps larger than 0.005 can cause the brass to overshoot and get sized smaller than anticipated. Once the brass leave contact with the sizing bushing it is no longer controlled in the sizing process and thus can end up with large runout (that is it is unsupported by the die.)
     
    The step is too big. My gun has a 0.3345 obturated neck diameter. I size it in 2 steps with a 0.338 and a 0.332 in a second sizing and get 0.0015 typical runout.
    {Now, technically, I am even pushing my luck as you should neck down only 0.005 per step while I am getting away with 0.006.}



    I disassemble my Redding competition sizer and clean and lube the sliding sleeve before each session. I also lube the cases even though I am using TiN sizing dies.



    Steps larger than 0.005 can cause the brass to overshoot and get sized smaller than anticipated. Once the brass leave contact with the sizing bushing it is no longer controlled in the sizing process and thus can end up with large runout (that is it is unsupported by the die.)

    I was going to post the same thing until I read Mitch's post. It makes a big difference if you step down the sizing in 2 steps. For your case, I would size first with a 340 or 339 bushing, then a 336 bushing for the final. You can do a 335, but I think you would be better served with a 336, which would give you 1.5 thou of neck tension, which is more than adequate. In the very least, get yourself a 339 bushing.
     
    Yes Sir, bushings are set to arrive this afternoon and I'll resume "stepping" the necks down as recommended. Ill report back in hopes this helps anyone else. Thanks all. I really appreciate it. Dave
    I was going to post the same thing until I read Mitch's post. It makes a big difference if you step down the sizing in 2 steps. For your case, I would size first with a 340 or 339 bushing, then a 336 bushing for the final. You can do a 335, but I think you would be better served with a 336, which would give you 1.5 thou of neck tension, which is more than adequate. In the very least, get yourself a 339 bushing.
     
    If you ignore the run-out and just load them up, how do they shoot?
    Dont know "yet". I just cant get past the runout to think about going out to shoot it. In my mind it seems with such a loose factory specs in the chamber it'd be futile to even shoot it with such "crooked" ammo.
    My neck bushings didnt show up today, not sure where the brown truck is at?
     
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    I am having similar result with 308 and I am using lee collet neck die...
    Has mostly started since brass has hardened and needs annealing but 001 to 002 shoot great the 004 to 006 shoot a lot worse, but I think its due also to neck tension being all over the shop...
    I have not turned necks so will try that and get neck tension consistent.
    Still learning...
     
    I have three different dies that I use from time to time for sizing. A Forster shoulder bump/neck sizing bushing die, a Lee Collet die, and a Forster F/L sizing die set for minimal shoulder bump.

    Of all the dies the Lee does great for neck sizing and needs no lube yet the Forster yields almost perfect cases when it comes to run-out. I anneal my cases after every firing then use the Forster F/L die. I also leave the expander ball in place. The design of the Forster die is such that the neck is being expanded while part of the neck is still in the neck sizing portion of the die. Results for me are case neck runout readings of less than .0005" ---- period. BTW, if you don't turn necks don't expect near perfect runout. Won't happen as long as the case neck thicknesses vary.
     
    I have been experimenting on the best way to size once fired Lake City 7.62 machine gun brass for minimal runout using a Lee collet die and a Redding full length bushing die. I tried a few different methods and made a few observations so far. My results aren't conclusive, but I think I have settled on a process that produces good results.

    1. Neck size with Lee die and bump shoulder with Redding die (no bushing) - runout using this method was, on average, lower than using the Redding die alone to size the neck. The extreme spread in runout was also higher. However the accuracy in practice just wasn't there. I know that the Lee die wasn't giving as much neck tension as the Redding bushing die, but I don't have a definite conclusion as to why this might cause worse accuracy.

    2. Full length size in 2 steps with Redding die - I sized the cases twice with progressively smaller bushings to avoid introducing excess runout by sizing the neck too much in one shot. The average runout for these cases was a bit higher than the Lee neck sized cases, but the extreme spread was much lower as well. The accuracy from this group of cases was better than with the Lee neck sized cases.

    3. Neck size with Lee die then full length size with Redding (bushing in) - I think this is the ticket to producing the best results. The cases from this group shot just as well as the cases from the Redding die group. Sizing with the Lee collet die first does two great things. First, it sizes down the neck without introducing excess runout so you don't have to do a double pass with the Redding die. Second, the Lee die does an incredible job of fixing heavily dented case mouths from the machine gun fired brass. The Redding bushing die gives you precisely the amount of neck tension that you want and the entire case is aligned within the die as you bump the shoulder and put the final size on the neck.

    Interestingly enough the same conclusion about sizing cases with unturned necks is noted here: The Rifleman's Journal: Reloading: Two-Step Sizing and Concentricity
     
    Neck turning is not required for excellent concentricity

    Could you elaborate. I find it hard to grasp how you can get the necessary concentricity when the ID of he neck which holds the bullet isn't concentric with the OD of the neck which is what comes in contact with the sizing die. You may see no runout when measuring the case only but what does it show at the bullet and vice-versa. Can't visualize how you can have no TIR at both locations if you don't have uniform case neck thickness.

    I suppose it's possible if you buy brass that's "perfect" but even Lapua lacks in that category. Better, yes. Perfect, no.
     
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    That was an interesting article. I think the best thing he did was sort the brass at the very beginning and use only brass that had minimal variations in neck wall thickness. He only mentioned that in passing and did not elaborate on the benefit of screening in the text.
     
    . However the accuracy in practice just wasn't there. I know that the Lee die wasn't giving as much neck tension as the Redding bushing die, but I don't have a definite conclusion as to why this might cause worse accuracy.

    I find that annealing first then using the Lee Collet Die gives the best uniformity of neck tension. Since you are "squeezing" the brass onto a collet any variation in spring back can be a pain. Neck tension is a major factor in controlling the powder burn by holding the bullet back until pressure builds. Varying neck tension, varying flame propagation rates. This is minimized by some shooters by jamming the bullet into the lands. Many of those who merely single load in their shooting discipline will often have so little neck tension they can twist the bullet in the case neck by hand. Some will soft load, leave the bullet seated long, and just let the closing of the bolt seat the bullet in the lands, letting the jam control their "powder burn".

    If you want more neck tension from a Lee Collet die, order a custom mandrel from them. Not expensive at all. Or you can merely polish down the one you have. I've done this to mine.

    The only bitch I have about the Lee Collet Die is that it leaves four evenly spaced ridges on the case neck. In order to make them go away you have to size each case then rotate about 1/8th turn and size again. PITA.
     
    I just turned some Lapua cases last night .0015 per side. I had two cases that only cleaned up 75%. That's cleaning the necks up by a total of .003 and some parts didn't get touched. Those went in the trash. They would have been "fliers" every time.
     
    I was battling this for almost a year.

    Tried sizing down in steps, Lee neck sizing die, different lubes, annealing, turning necks.

    Here is what helped:

    1. Annealing
    2. Replacing the Redding bushings with Wilson bushings in my Redding FL S Bushing die.

    The Wilson bushings brought my concentricity to approximately .0005, whereas the Redding bushings left my runout at .001-004!

    Don't know why this is.....even last night I was sizing .223 necks with the Wilson bushings, and for the fun of it, put in a Redding Bushing.....runout was ruined.

    I now use all Wilson bushings.

    PS. I discovered all of this when I purchased a Wilson neck sizing die, which came with a bushing. Runout was at or below .0005 using this die and bushing, so I decided to try the bushing in the Redding S die. Concentricity remained excellent.
     
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    I was battling this for almost a year.

    Tried sizing down in steps, Lee neck sizing die, different lubes, annealing, turning necks.

    Here is what helped:

    1. Annealing
    2. Replacing the Redding bushings with Wilson bushings in my Redding FL S Bushing die.

    The Wilson bushings brought my concentricity to approximately .0005, whereas the Redding bushings left my runout at .001-004!

    Don't know why this is.....even last night I was sizing .223 necks with the Wilson bushings, and for the fun of it, put in a Redding Bushing.....runout was ruined.

    I now use all Wilson bushings.

    PS. I discovered all of this when I purchased a Wilson neck sizing die, which came with a bushing. Runout was at or below .0005 using this die and bushing, so I decided to try the bushing in the Redding S die. Concentricity remained excellent.

    Interesting, and Im listening.
    Thanks to all, I have now been waiting for my neck bushings whne they should have been here on Wednesday, so no progress to report yet. Hopefully today, and hopefully some success. Thank you to all!
     
    Your problem is 2 fold. You don't turn your necks to a consistent diameter and you are sizing the necks down too far in one step.
    Agree on both counts.
    Since you are dealing with Remmy brass, odds are they'd benefit greatly from some quality time with a neck turner. Then, adjust your bushing size, as needed & check for runout again...
     
    Neck bushings just arrived, finally!
    Ok, here you go guys, and again, thanks for the input, it is greatly appreciated.
    Using Redding comp die set for the 300 RUM, Redding T7 press, I started with a fired neck of .344. This was decapped, wet tumbled and annealed prior to working the brass at all.
    Stepped it down 4 different steps relative to the neck bushings. 341, 339, 337 then the final of 335. The few that I just completed so far "started" with less that .001 runout.
    After pass number 1, 341 bushing, the runout grew to about .0015, then stayed the same for pass number 2, .339 bushing.
    Pass number 3 started to see a bit more runout, not much, and probably less than a half a thousand more, or .0017, and that stayed the same on the final pass using the .335 neck bushing. So I am probably gaining a .001 plus from the starting point to my finished brass, and that I can live with.
    Second benefit was that the stepping has left the brass at the size the neck bushing actually is on all 4 passes. Previous attempts with the big jumps, most often left me with a lesser measurement than the actual bushing neck diameter, I am now convinced that one cannot take big jumps relative to neck sizing.
    Worthy of mentioning, and before I got to excited, I did full length size, bumping the shoulder back .002, and it brought the brass neck back to a measurement just a bit over .001. So yes, what I am saying, is that after full length sizing, I gained a "bit" more concentricity in the necks!
    I am sure that neck turning would clean this runout up even more, but for now, and for guns that I am doing the load workups on, (Stock Sendero II chambers) this will suffice for me to get back to the business at hand.
    Again, thanks to all that jumped and I do believe all the suggestions and experiences were noteworthy, but the stepping has mostly fixed my issue, I hope this helps someone else out. Dave
     
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    Could you elaborate. I find it hard to grasp how you can get the necessary concentricity when the ID of he neck which holds the bullet isn't concentric with the OD of the neck which is what comes in contact with the sizing die. You may see no runout when measuring the case only but what does it show at the bullet and vice-versa. Can't visualize how you can have no TIR at both locations if you don't have uniform case neck thickness.

    I suppose it's possible if you buy brass that's "perfect" but even Lapua lacks in that category. Better, yes. Perfect, no.

    That is a fair question you have posed. My experience has been mainly from observation, but I can try to explain what I believe is contributory.

    What you are saying about the ID of the neck being out of sync with the OD is true; the outside may be very round after sizing, bit the imperfections have been transferred to the inside. However, brass is malleable relative to a bullet. So when you seat a bullet using a good seating die, it goes in straight, and the ID of the brass conforms to the shape of the bullet, which is more or less as round as you can hope for. For this reason, the bullet will be very straight.

    You could argue that there may be slight variation in the uniformity of the neck tension around the neck due to the imperfections of the neck wall thickness. However, how contributory is this to the bullet's trajectory down the barrel? I believe that the neck tension kind of evens itself out throughout the neck, with marginal imperfections.

    I don't routinely measure runout or concentricity in my loads, because there is nothing else I can do to try to improve it. I am already doing what I believe is the best I can do without spending too much time chasing variables that yield minimal returns. I can tell you that when I have measured my concentricity in the past, my runout was .001 or less. As long as your necks are 90 degrees square with the longitudinal axis of the case, you should get good results. This is attained by step down sizing as suggested above. If you can, neck size first, then F/L size.
     
    Neck bushings just arrived, finally!
    Ok, here you go guys, and again, thanks for the input, it is greatly appreciated.
    Using Redding comp die set for the 300 RUM, Redding T7 press, I started with a fired neck of .344. This was decapped, wet tumbled and annealed prior to working the brass at all.
    Stepped it down 4 different steps relative to the neck bushings. 341, 339, 337 then the final of 335. The few that I just completed so far "started" with less that .001 runout.
    After pass number 1, 341 bushing, the runout grew to about .0015, then stayed the same for pass number 2, .339 bushing.
    Pass number 3 started to see a bit more runout, not much, and probably less than a half a thousand more, or .0017, and that stayed the same on the final pass using the .335 neck bushing. So I am probably gaining a .001 plus from the starting point to my finished brass, and that I can live with.
    Second benefit was that the stepping has left the brass at the size the neck bushing actually is on all 4 passes. Previous attempts with the big jumps, most often left me with a lesser measurement than the actual bushing neck diameter, I am now convinced that one cannot take big jumps relative to neck sizing.
    Worthy of mentioning, and before I got to excited, I did full length size, bumping the shoulder back .002, and it brought the brass neck back to a measurement just a bit over .001. So yes, what I am saying, is that after full length sizing, I gained a "bit" more concentricity in the necks!
    I am sure that neck turning would clean this runout up even more, but for now, and for guns that I am doing the load workups on, (Stock Sendero II chambers) this will suffice for me to get back to the business at hand.
    Again, thanks to all that jumped and I do believe all the suggestions and experiences were noteworthy, but the stepping has mostly fixed my issue, I hope this helps someone else out. Dave

    4 steps...damn that is a lot. I think that you could accomplish your goal in 2 steps. Try the 339 bushing, then the 335 and see how that works. .001-.002 of runout is not bad at all; it is actually very good. Compare that to the 7 to 9 thousandths you were previously getting.
     
    I don't routinely measure runout or concentricity in my loads, because there is nothing else I can do to try to improve it.

    I do and I belive that there is much that can be done to improve it. It starts at the beginning. Turning the neck so it's totally uniform in thickness. Firing then sizing with a high quality die will then yield a case that has both the ID and OD of the neck that are concentric with the case body. I find that cases measuring less than .001" TIR on the outside of the neck will almost always yield a TIR of the same when measured on the seated bullet.

    It's not a matter of improving after the fact but a matter of eliminating the variables before a bullet is seated.

    Ideally, I would envision a sizing die that formed the case using all the same dimensions found in the chamber it's going to be used in but rather than over sizing then expanding, the case would be sized exactly the correct amount (allowing for spring-back) then reamed for a correct ID. The Reamer would be guided by the body of the sizing die so it followed the exact axis of the case while held in "chamber like" conditions.

    Today we cut the outside dimension to a smooth and pretty finish yet the part of the case neck that interacts with the bullet is whatever it is. Sometimes not too smooth.
     
    4 steps...damn that is a lot. I think that you could accomplish your goal in 2 steps. Try the 339 bushing, then the 335 and see how that works. .001-.002 of runout is not bad at all; it is actually very good. Compare that to the 7 to 9 thousandths you were previously getting.
    I totally agree with you, but remember I was chasing a gremlin and wanted to be as cautious as I could to keep this under a .001. And yes, now that I know what I do, I will try to step it up in more of a larger margin. Thanks
     
    Someone needs to perform an experiment, comparing loads with little to no runout to loads that have been bent noticeably, and see how bad the groups differ from one another. If this has already been done, can someone shoot me a link?
     
    I do and I belive that there is much that can be done to improve it. It starts at the beginning. Turning the neck so it's totally uniform in thickness. Firing then sizing with a high quality die will then yield a case that has both the ID and OD of the neck that are concentric with the case body. I find that cases measuring less than .001" TIR on the outside of the neck will almost always yield a TIR of the same when measured on the seated bullet.

    It's not a matter of improving after the fact but a matter of eliminating the variables before a bullet is seated.

    Ideally, I would envision a sizing die that formed the case using all the same dimensions found in the chamber it's going to be used in but rather than over sizing then expanding, the case would be sized exactly the correct amount (allowing for spring-back) then reamed for a correct ID. The Reamer would be guided by the body of the sizing die so it followed the exact axis of the case while held in "chamber like" conditions.

    Today we cut the outside dimension to a smooth and pretty finish yet the part of the case neck that interacts with the bullet is whatever it is. Sometimes not too smooth.

    I should have mentioned that I refuse to turn necks. I already probably do too many steps, and to this day, I have no clear tangible evidence that my efforts produce ammo that shoots any better than stuff loaded on my 550 with minimal brass prep. It just makes sense to me to do things the way I am doing them now, and it is not too labor intensive as of yet.
     
    I should have mentioned that I refuse to turn necks. I already probably do too many steps, and to this day, I have no clear tangible evidence that my efforts produce ammo that shoots any better than stuff loaded on my 550 with minimal brass prep. It just makes sense to me to do things the way I am doing them now, and it is not too labor intensive as of yet.

    If what you load is accurate enough for YOU then fine. For those that want group sizes less than .25 MOA, and more importantly, have have sub .25 MOA accuracy on ALL shots, then more case prep is in order. Is the goal is to merely "make a deer fall down" or make a 10" steel place go "booiing", no sweat. You're good to go.

    Neither one of us has the "ONLY" way to create a hand-load. It really depends on your expectation as to which one's methods provides the results they desire. Consider even that many people only shoot Factory ammo and it's just fine for them. Me? I haven't shot a factory loaded round in years, other than to run one over the chronograph from time to time to see if it's "telling lies".
     
    Deadshot,

    I am listening!!!! Do you care to spend the time explaining to me/is your neck turning process, specifically including the equipment you use/recommend. I am this Fn far into this reloading thing, I would always wonder if I am leaving something on the table if I dont at least give it a go and learn it.
    As with most things, Id prefer to use with what is proven to work versus the buying and experiencing Brand XXX didn't work and shouldve went with brand XXX.
    Thanks

    If what you load is accurate enough for YOU then fine. For those that want group sizes less than .25 MOA, and more importantly, have have sub .25 MOA accuracy on ALL shots, then more case prep is in order. Is the goal is to merely "make a deer fall down" or make a 10" steel place go "booiing", no sweat. You're good to go.

    Neither one of us has the "ONLY" way to create a hand-load. It really depends on your expectation as to which one's methods provides the results they desire. Consider even that many people only shoot Factory ammo and it's just fine for them. Me? I haven't shot a factory loaded round in years, other than to run one over the chronograph from time to time to see if it's "telling lies".
     
    Deadshot,

    I am listening!!!! Do you care to spend the time explaining to me/is your neck turning process, specifically including the equipment you use/recommend. I am this Fn far into this reloading thing, I would always wonder if I am leaving something on the table if I dont at least give it a go and learn it.
    As with most things, Id prefer to use with what is proven to work versus the buying and experiencing Brand XXX didn't work and shouldve went with brand XXX.
    Thanks

    My process is fairly simple. First, I shoot all new brass before I neck turn. A day at the range "fire forming" using all the leftover bullets (or the free ones I got from Hornady in their 'Get Loaded' promo) lets me make sure that the case has had at least ONE expansion cycle on it before cutting the necks.

    I size using a Forster Benchrest Full Length Die and leave the expander ball in place. I then turn the necks using a Forster neck turning tool and holding the case in a sinclair case holder that fits in my cordless drill. A little "90 weight" applied sparingly to the mandrel on the turning tool keeps the case from transferring brass to the mandrel while turning.

    I set my cutting depth so that I cut at least 270 degrees around the case neck circumference but no more than JUST 360 degrees. The idea is to make the neck uniform not necessarily thinner (unless you have a custom chamber that required a turned down neck). When I find a case that cleans up with 270 degrees of "cut" and leaves just scratches on the remainder of the case I use that setting for all cases in that batch (usually 100-200 cases in my "batch"). At this point it would be good to note that cases should be trimmed for uniform length so the neck turning is uniform in length as well (the tool has a stop on the mandrel). Over the years I've found that my Lapua brass ends up with .014" neck thickness and my Winchester with .012".

    When finished neck turning I clean in SS Pins and when finished I anneal (Helps speed the drying process).

    Once done this process is finished for the life of the case with the exception of continued cleaning and annealing.


    As an added step I take the "batch" and then sort it into 50 round boxes by weight and try to keep that batch together through it's life. When primer pockets start to loosen or I then dump the "batch" into my box of "fun shooting" or "sighter/fouler" box of brass. That brass then just gets tossed out by the ejector and swept up at the end of a shooting session (or grabbed by the brass rats). I then start again with a couple hundred NEW pieces.

    Note: The Forster Die I use has feature where the expander ball starts to expand the case neck while part of the neck is still in the sizing portion of the die. It matches the mandrel size on the turning tool and the runout measured on the case equals merely that of the case neck thickness variation. Near ZERO after turning.

    There are several neck turning tools that work great but one of them IS NOT the RCBS Tool. Avoid with all possible effort. K&M, Sinclair, or Century 21 are great as is the Forster.
     
    Someone needs to perform an experiment, comparing loads with little to no runout to loads that have been bent noticeably, and see how bad the groups differ from one another. If this has already been done, can someone shoot me a link?

    Read Tony Boyer's story about concentricity. He was at a match. There was a guy with a concentricity device that measured loaded rounds and would reduce concentricity. Tony brought him some rounds to measure. Tony's book says, "Concentricity ranged from .001" to .005". That sounded significant, and the vendor indicated that they probably would not shoot. I did not allow him to straighten them out. Instead, John and I went off to shoot them. After a couple of groups in the low teens, we looked at each other and decided we did not need that gadget." You may not be familiar with benchrest terminology. A group in the low teens would measure 0.110 to 0.140 - something like that. Groups in the low teens are pretty rare, even today. Tony Boyer's book is titled "The Book Of Rifle Accuracy". Tony and Faye Boyer have won more benchrest matches than everyone else.
     
    Read Tony Boyer's story about concentricity. He was at a match. There was a guy with a concentricity device that measured loaded rounds and would reduce concentricity. Tony brought him some rounds to measure. Tony's book says, "Concentricity ranged from .001" to .005". That sounded significant, and the vendor indicated that they probably would not shoot. I did not allow him to straighten them out. Instead, John and I went off to shoot them. After a couple of groups in the low teens, we looked at each other and decided we did not need that gadget." You may not be familiar with benchrest terminology. A group in the low teens would measure 0.110 to 0.140 - something like that. Groups in the low teens are pretty rare, even today. Tony Boyer's book is titled "The Book Of Rifle Accuracy". Tony and Faye Boyer have won more benchrest matches than everyone else.

    I was expecting results similar to that. There, that goes to show you that a lot of this effort we kill ourselves with, trying to create the perfect handload may be in vain. However, I will continue to make straight ammo for pride if nothing else
     
    I only brought it up so that we would all know why we do some of this stuff.

    My favorite gunsmith one said that there are only 7 things that matter to the accuracy of a rifle. And the only tricky thing is: which seven.

    I use a Sinclair priming tool. I use Redding and RCBS dies. I seat bullets with a Wilson seater. I don't measure concentricity - I don't even have a tool. I weigh every charge with a chargemaster. I shoot out of a magazine so it probably doesn't matter. I can usually hit an IPSC target at the ranges that matter to me. I was banging 6-inch steel at 600 yesterday and acceptable groups at 1,000. I have fun and I shoot most weekends. I no longer compete except for cookies or cold drinks at the range. I learn from you guys.

    Have fun, stay safe, try new stuff, don't spend all of your money.