Forming 7mm-08; better to neck up or down?

[longrangehunter]

Always up so you do not have to neck turn. I am a lazy bastid!

Myself included, but since the 308 brass was $27.50 cheaper per hundred I went w/them. I had thought making the neck thicker would have been a good thing, only it was too much of a good thing! So now I'll have to turn the brass necks down.

 

[Oldtrader3]

Prolly .260 brass would work better, if you can find it?

 

[longrangehunter]

Using 308 brass is by far more cost effective. I bought another two boxes of Lapua brass at Cabela's on sale, $65.00 per 100, and got another $25.00 off at the cash register! Bringing the cost down to .56 cents each with tax, now that's cheap!

I've been neck turning them down to .3145". I think having the false shoulder from the bushing die not sizing the whole neck all the way down, and the tight neck situation was the cause of the erratic behavior of the already proven load I had using Federal and Winchester brass in my Tactical 7mm-08 rifle. I had to order a standard F/L die and then neck turn. Time consuming for sure, which I'm not a fan of either but oh well, I've already made a commitment using the Lapua brass I have.

Hopefully I'll do well at the JC Steel Target Challenge in March, I'm in the process of converting the rifle to PTG bottom metal and Accuracy International Magazines from a BDL version. I hope that conversion goes without a lot of modifications to the stock? I'm hoping the Post Office has it today? I know I wont like using the HOG Saddle as much vs. the BDL bottom metal only because the rifle can be mounted more centered directly over the tripod.

 

[longrangehunter]

Wow..... I would never like to neck turn another piece of brass in my life again! Pain in the butt, sore palm as well from holding onto the case holder tightening and doing the neck turning its self.

My thoughts:

Neck up if at all possible. No need to neck turn since the brass neck will thin during the process.

If you neck down, I hope you have a factory chamber and not something cut like a match chamber or you might be doing a ton of work for very little gain. I found the best way with the end result being better is to turn the case first, then neck down. Or make it even easier on yourself and just inside neck ream the darn case.

Here's why:

The factory new parent case will have perfect parallel sides on the neck after running it over the mandrel. Which will prevent any excess brass from being removed that is not fully sized in the die at the neck shoulder juncture if you've already sized down.

If by chance the case as been already fire formed, then turning after will also produce a more concentric neck then if it wasn't fire form first.

I use at least a 6x magnifying glass to check the progress of the neck turning. If you turn a new unfired unsized parent case and turn the neck "to" the shoulder, you'll see that after sizing down the turned portion will become part of the new neck formed, and it will look uniform. vs. if you turn a neck down case, you will need to cut just to the point that the cutter puts a beveled edge on the shoulder. But here the deal, you'll notice when the cutter is 4/5 of the way down the neck it will start to remove move material with each turn then the rest of the neck or if done on a factory parent case or a fire formed case. That's because during the necking down in the sizing die the brass has moved to not only make the neck thicker but more brass moved into the neck shoulder juncture that the sizing die... the "dreaded donut" and/or a false shoulder will appear. Which is why you'll need to neck turn all the way to the neck shoulder juncture. You'll also need to resize again after turning the neck, where the sizing button will iron out the donut to the out side of the neck. Which you'll avoid doing that twice if you neck turn the parent case first, or a neck reamer can be used to remove the donut/and or the neck thickness of the parent case in the first place if you'd like to forgo the neck turning altogether!

Either way avoid the hassle and buy properly head stamped brass and enjoy all that extra time shooting, hunting or watching TV for that matter. Me I still have 325 pieces of brass to do...... so I bought myself some nice gloves with blister armor in the palm so I can maybe actually finish this job I wish I didn't have to do!

 

[longrangehunter]

The PTG trigger guard went in nice with a very little material removal from the stock, only the magazine wouldn't fully engage because of a depth issue. The magazine was making contact with the action's bottom before the latch could lock the magazine into the bottom metal...... that sucks! So now I'll try a Watt's Outdoors DBM bottom metal and see if that works?

 

[elkeater2]

I neck down because I don't know any better. Or maybe because I started my reloading career long ago making 7x57 out of milsurp 30-06. My most recent intentional neck down was for a 25-06 - I had gotten a batch of actual 25-06 that was toward the short end of the stick. It stretched enough on first firing in my max spec chamber that case life was very short. I made up some brass from .270 Win, a small batch, just to verify my suspicions and I was right. The real advantage to me was being able to precisely control the headspace relationship and create snug cases for first firing. BTW - I take a Sharpie and colorize the rim groove on these cases that aren't what the headstamp says. So far it has prevented confusion!
EE2