Neck tension

[swampbug]

Uhm, he said .005 in some ( that's 0025 per side) and .001 in others.
That's 0005 per side ( but I went to public school) and he uses that for a 300 RUM ( not exactly a competition rifle). I'm just saying not many people would consider that advisable or safe.

 

[Hugnot]

I try to make this as simple as possible.

If I can't easily slip fit a bullet into a fired case I turn the neck to get a slip fit into fired cases. I use a RCBS neck turner, maintain blade edge with diamond file, & chuck brass into my Dewalt cordless - works up to .473 & slightly more.

Upon turning the neck(s) to enable a slip fit into fired case necks; I remove the expander from my F/L die.

After F/L resizing I use a Lee collet die to compress neck around mandrel.

The kicker is brass spring back - annealing case necks will help - increase brass grain size & reduce work hardening. Crimping bullets using the Lee crimp die helps - exceeds brass elastic limit and spring back.

Almost all brass has neck walls thicker than needed. This can be fixed by neck turning or use of bushing dies or having die necks honed out.

I use a simple loop tip with propane. The oxidizing part (just at the end of blue flame, flame must be blue) of the propane has a temp of over 3,500 F, - anneals brass real quick.

F/L die bushings are available in increments of .001. Forster can hone out or increase diameter of their F/L dies in increments of .001. Avoid working brass as much as possible.

Chamber temperature variations may result in expansion/contraction of ammo diameters less than .001.

 

[Ackley Man]

Arbor Press | K+M's Precision Reloading Best Arbor Press

Arbor Press | K+M's Precision Reloading Best Arbor Press used w/ inline bullet seating and neck sizing dies for a home loading bench or out at the range.

kmshooting.com

 

[Phil Rizzo]

that is one great way to monitor some of my "variable elimination" efforts.

 

[BrentM]

Speaking of run out...... so I dug out my concentricity gauge last night...... Thinking about this thread the million different views and direction it has gone, one thing I recall is run out being brought up. I am currently running non turned adg brass for this chamber and decided to see if how bad run out is with my current choice. Loaded neck was .2945, .291 bushing, .292 K&M Mandrel. Based on my math we are .0025 and od is showing .292 on my calipers. I took 2 pieces of the adg brass and turned with a 33 degree cutter for .0005 cut. Total of .001 that cleans up 95% of the neck. Used a .290 bushing.

The turned brass is a little less run out but here's the deal, I loaded 25 rounds and the max RO was .002 and most were .001-.0015. I guess that's another vote for less neck tension on the neck sizing part of the process if run out is a big hang up for a person.

 

[Beluebow]

that is one great way to monitor some of my "variable elimination" efforts.

At what point do you say this is a cull round/fouler/sighter? And how much difference did the outliers shoot at distance?

 

[Phil Rizzo]

5 is about the max variation I see these days.
Seating force is 30-70 depending on the cartridge.
Combine that with minimum runout, it's good stuff.

recently i started using a Giraud 3 way trimmer, for uniform length and chamfer.

 

[pdog shooter]

I shoot for 001 / 0015 measured neck tension. F class only. Can not measure seating pressure but the best thing for me concerning concentric outcomes and a good uniform "feel" from full size die to seating would have to be induction annealing. Never could get that with flame. May have been stated already but theres a lot of reading here.

 

[BrentM]

I shoot for 001 / 0015 measured neck tension. F class only. Can not measure seating pressure but the best thing for me concerning concentric outcomes and a good uniform "feel" from full size die to seating would have to be induction annealing. Never could get that with flame. May have been stated already but theres a lot of reading here.

Not really but another rabbit hole. I made my own induction annealer and 100% agree it is much easier to control the annealing process and more consistent. I built a flame annealer that works well but the flame was not that consistent. With induction it's just a timer switch dialed to .1 and get to work.

 

[swampbug]

For F Open, I use a .002 under mandrel and with springback I end up with .0015 verified with guage pins. I do have to be careful though. Some bullets I use, I load long, say .008 past touch, and if I chamber them and then have to open the bolt, the bullet can stick in the lands. Not fun.

 

[BrentM]

For F Open, I use a .002 under mandrel and with springback I end up with .0015 verified with guage pins. I do have to be careful though. Some bullets I use, I load long, say .008 past touch, and if I chamber them and then have to open the bolt, the bullet can stick in the lands. Not fun.

Did that once on a hunt based on some bs advice from a dude I thought knew what he was doing. Back then running bergers we jammed about .010...... That was last time I jammed anything for any reason. I am not opposed to a range rifle, beside the mess, but I have tools to deal with it. In the back country...... not so much.

 

[2buffalo]

Consistency VS tune

I want to address something about reloading and tuning a rifle. Theres a lot of information being circulated about different processes done at the reloading bench in the name of consistency. Most of the time these processes are being recommended because they make more consistent measurements...

www.longrangeonly.com

A good example of the effect of neck tension

I met a buddy at the range to see how his 25 prc I chambered was tuning up. This is such a great example of how much neck tension can effect the tune. I really struggle getting this across to some people so pictures like this are great. 2 ladders shot back to back at 600 in mild conditions...

www.longrangeonly.com