Rookie neck tension question

[chav0_12]

Do you find either process helps with concentricity better than the other? I've heard from some they feel a mandrel will do a better job of straightening or uniforming the neck after the sizing process? Just curious of others opinions.

I haven't compared the two. I will try to though. Also don't want to mess with a process that's working.

 

[MarkInPA]

I have heard that,as mentioned above, if you're not using quality brass with consistent neck thickness then just using a bushing from the outside may give uneven tension due to neck thickness variance. With quality brass it's not usually an issue. Obviously plenty of people just use the bushings and get good results. One of my spring projects is going to be testing my regular dies which give about .002 to a bushing with .002,.003 and .004 and see if I can tell any real world difference.

I think this is why it good to finish the sizing operation from INSIDE the neck. Whether that be a sizing button or a mandrel. By so doing, any case neck thickness variations are pushed to the outside and you are left with a uniform inside diameter.

If you are turning your case necks and create an even case neck thickness, then maybe you can forgo sizing the inside of the case neck.

For someone using factory rifles for hunting purposes, they probably are not turning their case necks.

 

[Rick Richard]

How exact do you think that is? There's already some tension on the bullet, so wanting .003 might net you .0035 or .004. That's all I'm saying I think it's easier and more exact using a a mandrel, same can be done with expander buttons but I think that just works the brass more than necessary. I've had good luck with bushing dies too, I've had good luck/noticeable differences playing with different tensions using different bushing sizes too. You don't think, just grabbing a mandrel of the exact size you wanted the inside of your neck to be would be more accurate? I think I hit on this too, as there have been reports of brass "acting funny" when annealed or not. I can imagine the brass acts differently the more and more it changes as we trim and anneal and work harden. To get that exact neck tension that we want it seems the mandrel would be the easier route. Again, idk for sure, I haven't personally done enough testing to say which is better. It just seems that a mandrel is easier.

Doesn't matter which method you use you will get "springer back" and have to adjust accordingly….with a different bushing or mandrel. The bottom line is how well does a rifle shoot with all variables being equal.

 

[Rick Richard]

I haven't compared the two. I will try to though. Also don't want to mess with a process that's working.

Exactly, we can agree on this. lol.

 

[Alibiiv]

Do you find either process helps with concentricity better than the other? I've heard from some they feel a mandrel will do a better job of straightening or uniforming the neck after the sizing process? Just curious of others opinions.

For me turning the case neck is the only process that will make the case neck wall thickness the same all around the neck. If a bushing die is used it will squeeze the brass in to get a particular neck size, but it will not make the outside of the case neck thickness equal all the way around. I have seen some case neck thickness out as much as .0015 thousandths. While turning case necks I've also found where the neck is slightly tilted off from the body of the case. It is no different than primer pockets. Anyone who has used a primer pocket reamer has noticed that the primer seats are not parallel with the base of the shell, some are crooked. This brass is mass produced and pumped out. It is mostly close to tolerances, but not necessarily so for every case. I think we've hijacked this thread??

 

[WahooYahoo]

I noticed no difference at all whether I turned the necks or not, weight sorted the cases or not, wished upon a star or not. But I shoot hunting rifles.

If I can repetitively get 3 shots in .5 minute, I'm thrilled. If I can shoot 10 under 1 MOA, just as good. I use very good components, keep my process consistent, from loading session to loading session and case to case.
I anneal before each loading for consistency and use LE Wilson (or Sinclair) chamber dies so no run out. As long as I do these basic things, all of the expensive and complicating processes add nothing.

In case you wanna try, I have a 21st century lathe, turning arbors, 21st Century Consentricity wheel, digital thickness guages, and a heap of other stuff. Like new.