Trouble with Redding Type-S FL Bushing Die

[Rmeju]

So, I've recently gone down the rabbit hole of concentricity gauges, neck turning, bushing dies, co-ax presses, etc. in an effort to eliminate unexplained flyers and hopefully shrink my groups.

In a nutshell, the issue I'm having right now with my Redding FL bushing sizer is that when I FL sized to get the brass ready for neck turning (using a Forster non-bushing FL sizer), that process brought the brass necks down from the ~.315" fired diameter to .305", and turning brought it down to .304". But my target tension tells me I want a .308", which is the bushing I bought.

So, now my necks are about .004" too tight for what I'm looking to do. Is there a way to fix this? I can't use the expander that came with the Redding Type-S die because it's too small, and even if it was big enough, it'd mess things up on its way back out of the neck, causing a different problem.

I suppose on my next lot of brass, I could just turn the necks without FL sizing the brass, although 1) I worry that if the brass fits too loosely on the neck turning mandrel (an extra .010" of wiggle room), that could cause problems with the turning operation, and 2) that doesn't help me with this current lot of brass.

Is there a step that I'm missing somewhere? Should I have skipped the pre-turn FL-size?

 

[roc1]

Why didn't use bushing die to start with FL sized oversized neck wasn't needed. Have to size to turn necks so next time size with bushing die may need even smaller bushing after turning necks may not have enough tension. I had that problem some brass needs different bushing after turning. I would load shoot too much tension won't hurt may need more sometimes with recoil anyway. Next time size with bushing die check with calipers see what outside is after uploading to make sure bushing is right after neck turning.
Hope helps little
Roc1

 

[iShoot17]

You could always use an expander mandrel (such as one from 21st Century, among other companies) to expand to inner portion of the neck.

I have also seen gentleman use a bullet puller die. By seating a bullet in a case, then pulling it, and leaving it locked into the die, you can now run each piece of brass into the die with the bullet slowly entering the neck. It is a "cheaper" option to buying an expander mandrel die. Although, if you've already gone this far, you might as well go pick a die and respective mandrel up!

 

[Walkalong]

Size them. Use a Sinclair, 21st Century (Whomever's) expander to get them the right fit for the pilot on the neck turner. You might have to do it in two steps. Remember, you can buy more than one size pilot as well with some neck turners. Some use the same design for expansion and the pilot, so you can just get two slightly different sizes of pilots/expanders. Turn them. Then size them using the proper neck bushing to get the neck tension you desire.

Are you just turning enough to clean up necks? Are you turning to fit a tight necked chamber?

 

[243winxb]

lyman universal case trimmer - Lyman Outside Neck Turner

now my necks are about .004" too tight

Load a boat tail bullet. Measure the loaded rounds neck diameter. Next loading use a bushing that is .002" smaller. The next loading with the bushing die will not over size the fired necks. My Lyman neck turner requires brass to be sized using a standard FL die , with expander, before doing the neck turning. http://www.lymanproducts.com/lyman/case-trimmers/outside-neck-tt.php

 

[Rmeju]

Thanks guys!

@Walkalong: I'm turning them to clean up the necks so I can get a uniform wall thickness. For me, that was .0125" (with a .284 bullet, and .001 tension, that's how I got to .308). I have an RCBS neck turner although I'm not sure they make a neck expander die like Sinclair, 21st Century, etc. I'll have to check.

I did see that the expander die companies don't seem to exactly specify how wide their mandrels are, they just say "7mm." I figure a .284+ mandrel would get me up to .309+, so I should probably be ok, although I imagine I don't want the neck fitting too loose on my neck turning arbor. Do the manufacturers specify their mandrel sizes somewhere, or do you just have to buy from the same manufacturer as your turner so that you can be sure it expands to just slightly larger than your same brand of turner pilot?

When you say that I might need to expand in two steps, do you mean that I might have to exapand twice to get the desired expansion?

Thanks!

 

[243winxb]

There are 2 RCBS neck turning tools.

.0125"

There are 2 types of RCBS neck turners. The one like my Lyman, used on the trimmer, requires brass to be full length sized in a standard die, with expander, before turning. The 1 RCBS is said to inside neck ream while outside turning?? If it does, i would not like it. Have not used an RCBS unit. http://www.rcbs.com/RCBS/media/RCBSMedia/PDFs/Instructions/English%20(EN)/CaseNeckTurningTool.pdf

 

[Rmeju]

No, that's not the one. It's the one with the micrometer. http://www.midwayusa.com/product/51...ase-neck-turner-with-quick-change-case-holder

 

[243winxb]

Ok. Good luck.

 

[atblis]

http://www.6mmbr.com/neckturningbasics.html

The Expander
The expander is closely matched in diameter to the cutter arbor, so you must use the same manufacturer's expander and turner if you expect to get good results. Let's set up the expander in the press; there's not much to it, it screws in like a die. The K&M expander comes with a long screw which you adjust to bottom out in the case just before the neck hits the expander body. Just measure the depth of a case with the back shaft of your calipers and set the screw about 0.050" longer than that. If you somehow bend the screw and are too embarrassed to call K&M for a replacement, I have it on good authority that you can get by just fine without it as long as you aren't too ham-handed on the press when you expand.

 

[Offfhand]

In order to avoid the frustrations and complications expressed but the OP, I've found it saves time and effort, and money as well, to simply buy a dedicated neck expander with the turning mandrel as a "matched set" from the same manufacturer. That way one can be more assured that the turning mandrel will fit properly for precise neck turning. The combinations are offered KM and Sinclair, and probably others. Attached is a photo of KM and Sinclair sets. Be sure to always buy carbide turning mandrels, the extra money is well spent.

 

[Rmeju]

Hey all, just got a k&m expander die set up. It opens my case mouths .001" wider than by bushing, which is prefect!

Thanks!

 

[Walkalong]

Excellent! And K&M makes good stuff.