Sizing with collet neck die + body die for autoloader

[MWAG19919]

I've read the "let's talk about precision reloading thread" as well as dozens of threads here and elsewhere about crimping vs not crimping, bushing dies, expander balls, expander dies, and the Forster FL sizing die. As with anything reloading related, there is no consensus on what is best.

Here's what I'm thinking of doing. I currently full length size my brass on a single stage (RCBS short base for range brass, Redding FL w/carbide expander for brass fired in my guns) and load the ammo on a Dillon 650. I use an RCBS seater and a Lee Factory Crimp Die, but I'll be switching to a Forster micrometer seater.

For my prep toolhead I'm thinking of using a Lee collet neck sizing die followed by a body die. I'm averaging .001 runout on my 7mm-08 brass using this method on a single stage press, but this is for a bolt gun. My question is this: will I run into problems if I adopt this method for AR-15s?

I'm a fan of the neck collet die because it produces very concentric cases, doesn't work my brass like an expander ball, works with brass of varying neck thickness, and does not require neck turning or experimenting with bushing sizes. I like splitting up the full length sizing into two operations because it allows me to independently adjust both operations. The con of having to perform two operations doesn't matter because I'll be using a progressive press for .223/5.56.

I always check my sized AND loaded rounds in a case gauge, but will I create problems that a case gauge wouldn't catch? I'm assuming no, but I'd hate to get a stuck case or something like that.

[markm]

For my prep toolhead I'm thinking of using a Lee collet neck sizing die followed by a body die. I'm averaging .001 runout on my 7mm-08 brass using this method on a single stage press, but this is for a bolt gun. My question is this: will I run into problems if I adopt this method for AR-15s?


Interesting. I always body size first. Never thought of the neck first, then body.

But no. You won't have any problems. You don't need to check every round in the gauge either. I test 5 or so if I mess with a die setting.

Those neck collet dies by lee are awesome for eliminating neck runout.

[bigedp51]

KISS..........Keep It Simple Stupid

The Redding bushing die FAQ tells you if the case neck thickness varies .002 or more then use the expander that comes with their bushing dies. Using a die with a expander is not the end of the world as many people think especially in off the shelf factory rifles. You have no control over how far the neck expands in a factory chamber and you have to reduce the fired neck diameter back down

Below I prefer Forster full length benchrest dies with their high mounted floating expander that greatly reduces neck runout.


https://www.youtube.com/watch?v=ac3iDJxDgxk

You can use any full length die and remove the expander and use a expander die. Below many AR15 reloaders use a Lyman type "M" expander for .003 bullet grip and reduced neck runout. And you just bump the case mouth onto the .226 section of the expander to aid straight inline seating.

https://i.imgur.com/ohIUcpd.png

Below I added a Forster expander and spindle assembly to all my Redding and RCBS dies to reduce neck runout. Why drag the longer Redding expander through your case neck with its increased pull.

https://i.imgur.com/kWbieba.jpg

[MWAG19919]

Interesting. I always body size first. Never thought of the neck first, then body.

But no. You won't have any problems. You don't need to check every round in the gauge either. I test 5 or so if I mess with a die setting.

Those neck collet dies by lee are awesome for eliminating neck runout.

Your way makes more sense. I was thinking neck first because it has the decapping pin, but I can do 1.) universal decapper 2.) body die 3.) collet neck. It’s not like I have a shortage of die stations

[markm]

Your way makes more sense. I was thinking neck first because it has the decapping pin, but I can do 1.) universal decapper 2.) body die 3.) collet neck. It’s not like I have a shortage of die stations

That's sort of how I do it. I run the universal Decap die, then wet tumble, then size, then neck.

[braindoc]

I wouldn't consider my self an expert on reloading but my experience has been positive for .308 bolt gun precision loads and lately an AR-15 55 grain general steel loads. The AR loads are good enough to hit a 2/3 size steel silhouette at 300 meters. Since I Wet tumble with pins I decided to use the Lee Collet Die to decap and squeeze the neck down and then after Tumble and dry use a Redding Body die to bump the shoulder back. In my particular AR I measure the headspace post firing with a Hornady Lock and Load Headspace Comparator and aim to bump the case shoulder back 0.003 in. So far I have no issues.

[Eurodriver]

You can use any full length die and remove the expander and use a expander die. Below many AR15 reloaders use a Lyman type "M" expander for .003 bullet grip and reduced neck runout. And you just bump the case mouth onto the .226 section of the expander to aid straight inline seating.

https://i.imgur.com/ohIUcpd.png



This is exactly what I do, and my rounds get sub MOA at 1,000 yards if the wind is gone.

[rjacobs]

I was going to get a body and neck and whatever dies for my 6.5c setup 3 years ago, but I did a bunch of measuring of my Forster full length die(im shooting a gas gun exclusively) and simply took the expander ball and spun it on a drill and some sand paper until it was sized where I wanted it. I got my 004 neck tension and I can do it in 1 step.

[Eurodriver]

I was going to get a body and neck and whatever dies for my 6.5c setup 3 years ago, but I did a bunch of measuring of my Forster full length die(im shooting a gas gun exclusively) and simply took the expander ball and spun it on a drill and some sand paper until it was sized where I wanted it. I got my 004 neck tension and I can do it in 1 step.

I think the issue many folks find isn’t the neck tension with expander balls but runout increases due to the lack of precision of the ball. Sinclair expander mandrels are what’s I use in 6.5 (can’t find an m die in .264) and it’s free floated so it centers itself in the case neck.

[opngrnd]

If you resize without the expander ball, will the case mouth even allow a collet neck die, or do you have to run a Lyman M die?

I might be reading this wrong, but it seems that I could decap, body size w/o expander, and collet or M die in one pass on a Hornady LNL.

[markm]

If you resize without the expander ball, will the case mouth even allow a collet neck die, or do you have to run a Lyman M die?

I might be reading this wrong, but it seems that I could decap, body size w/o expander, and collet or M die in one pass on a Hornady LNL.

You could do this. Pretty much what I'm doing with my neck expander die.. after sizing without an expander ball.

[rjacobs]

I think the issue many folks find isn’t the neck tension with expander balls but runout increases due to the lack of precision of the ball. Sinclair expander mandrels are what’s I use in 6.5 (can’t find an m die in .264) and it’s free floated so it centers itself in the case neck.

I dont know. I dont measure runout. I do what I can, but I dont go overboard. Chargemaster powder thrower and a Co-Ax with Forster micrometer dies. Thats as complicated as I get.

When I prep my .223 brass I use a mandrell from 21st century shooting, but thats because I universal de-cap, then size/trim in one step on a Dillon, then I run the mandrel through as the last step.

[Kansaswoodguy]

I don’t have time for extra reloading steps for 223 and chasing low runout is a fairy tail. I just loaded up cases with .001” runout and .005” runout no difference on the target at 385yds. Matching your bullet weight to powder is the greatest increase in accuracy you will gain. The Sierra and Nosler reloading manuals list their accuracy powders for bullet weights these are great places to start. Next big increase in accuracy is trimming your brass.

[markm]

I don’t have time for extra reloading steps for 223 and chasing low runout is a fairy tail. I just loaded up cases with .001” runout and .005” runout no difference on the target at 385yds. Matching your bullet weight to powder is the greatest increase in accuracy you will gain. The Sierra and Nosler reloading manuals list their accuracy powders for bullet weights these are great places to start. Next big increase in accuracy is trimming your brass.

I don't really sweat runout on Tangent ogive bullets. But it's nice to keep it minimal. The single biggest reason I run the neck sizing die was to get rid of the case stretch and abuse that the expander ball delivers.

Having to run a second die to size brass is a bit of a drag. But I make up for it on case trim because the cases just barely kiss the cutter due to almost zero case stretch. So I fly right through a tote of brass.

[Daniel44114]

I can still full-size with a shoulder die, normally on the LR bolt stuff I bump the shoulder .001-.002" on the semi auto stuff I bump .003"-.004" which so far has produced cases that will fit any of our semi's..I suppose if you had a rifle chambered on the high side of SAMMI and one chambered on the tight side you might have to size cases more than .03-.004" but I haven't run into that with our rifles...