300WM Peterson brass help

[staghunter]

Looking for a little help here from you guys. Bought some Peterson 300WM Long brass. Was going to start loading them and upon measuring the inside neck dia. I found they are between .302 and .3035. That seems like way to much neck tension to me. I was expecting to put about .002 on it.
I will be loading them with HH 180gr about .0020 off and I'm putting a factory crimp on them.
Should I get a mandrel die and resize the necks out to about .306. If so which do any of you have work experience with and recommend.
Any help would be appreciated. Love this group of guys. So much knowledge in one place is exciting to read all the comments.

 

[DoneNOut]

Have you tried seating some empty cases to feel the tension? My Nosler bullets seat tighter than my Hornady. Just FYI. You could also anneal the necks which reduces neck tension a bit.

 

[MagnumManiac]

Do you have a regular FL Die or Neck only Die?
If a FL Die, adjust it so that the complete neck gets sized, unless it is touching the shoulder.
If a Neck die, just run through and get your .002" or a bit more neck tension.
Mandrels will make little difference on unfired brass, as it hasn't expanded from firing yet. You could do it that way if you want.
I run Sinclair and 21st Century mandrels…take your pick, they both work.

Cheers.

 

[dok7mm]

You've got the right idea! I use .0015", .002 and .003" mandrels , then test for for best neck tension.

 

[jakeSCH]

Hammers love neck tension so I wouldn't worry about it. It seems to give better ES results. I have no issue running 4 or 5 thou...though I haven't run 6 yet.

I would load up a few and test them out before you try other things.

 

[staghunter]

If I run them as is which I'm not against then if I get good results I would need to be able to reproduce that neck tension. Agreed?

 

[jakeSCH]

If I run them as is which I'm not against then if I get good results I would need to be able to reproduce that neck tension. Agreed?

Yeah, depending on your die you may not be able to replicate it. But usually loads change after first firing anyway (at least a little) as the brass is fire formed to your chamber.

I started pulling all expander balls on all my dies when I resize and going to use hammers…and don't expand them. It helps due to pdr design.

 

[Tiny Tim]

I don't believe you will be able to maintain that level of interference fit. You will likely exceed the yield strength of your brass. Sounds like you're using a standard fl die which is overworking your brass. Without annealing this "tension" will increase as you work hard your brass and introduce another variable to your reloading process. If not shooting a custom chamber I would look to a custom or bushing die to get you the proper interference fit. You will be better off in the long run. In the meantime, just run them as the come out of your die and play with your crimp die and see how it shoots.

 

[staghunter]

Thanks all for your input. It's all good advice and appreciated.

 

[QuietTexan]

Should I get a mandrel die and resize the necks out to about .306. If so which do any of you have work experience with and recommend.

I bought the full 30-cal kit from 21st Century, every mandrel I should ever need in 0.0005 increments.

Caliber Specific Expander Mandrel Kits

Our caliber specific expander mandrels are available in .0005” increments in calibers 22 to 338 and will range from .001” above bullet diameter to at least .003” below bullet diameter depending on caliber. This will allow the reloader to find proper neck tension to fine-tune their loads. The...

21stcenturyinnovation.com

K+M also makes a nice mandrel set. LE Wilson makes "new brass" that is aimed at getting to 0.0015 under caliber but it's one mandrel and not a set so is really only useful on new brass.

 

[whatnext]

I run a Wilson mandrel on new brass after inside/outside chamfering, load and shoot to fire form to your chamber. This irons out any imperfections that developed during packing/shipping and in your case, will get you closer to desired neck tension without jamming a bullet in an undersized neck. Mandrels run smoother if you dip every second or third case mouth in Imperial Dry Lube. I believe the Wilson mandrel is -.003". After that go back to your normal reloading program.

 

[staghunter]

I run a Wilson mandrel on new brass after inside/outside chamfering, load and shoot to fire form to your chamber. This irons out any imperfections that developed during packing/shipping and in your case, will get you closer to desired neck tension without jamming a bullet in an undersized neck. Mandrels run smoother if you dip every second or third case mouth in Imperial Dry Lube. I believe the Wilson mandrel is -.003". After that go back to your normal reloading program.

Got a set of Wilsons on the way to do just that. Thanks for the other advice also.