What size neck bushings are you using on your 300 Norma (Norma brand brass)? I don't have my brass yet so I can't measure neck thickness but I want to get my bushings ordered. Just trying to get a rough estimate for what others are using. Thanks.
300 Norma Neck Bushing Size
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Thanks for the input, but I understand the 300 brass is a bit thicker than the 338 brass in the neck area?
It might very well be. My 'smith has run .300Norma brass to form cases for that same wildcat, so I doubt its appreciably thicker?
My (necked down) loaded rd. nk. dia. is .338-9". Fired case has a .342" neck...
If straight .300 Norma brass is indeed thicker, you could still get away with a .335 bushing to start with. 4-5 thou. of neck tension shouldn't be too much in that big a case. And have a .336 on hand, if you want to go easier with the tension...
My (necked down) loaded rd. nk. dia. is .338-9". Fired case has a .342" neck...
If straight .300 Norma brass is indeed thicker, you could still get away with a .335 bushing to start with. 4-5 thou. of neck tension shouldn't be too much in that big a case. And have a .336 on hand, if you want to go easier with the tension...
I measured three loaded rounds and they all measured 0.3385". I would run a 0.336" bushing. This is with Norma Brass and a 215 Berger Hybrid.
I run the .335, but I'm going to give the .336 a go on the next round. I am not happy with neck tension consistency right now.
I could use that info too. My first venture into both reloading for 300 NM and using bushings. I have the Lapua brass as well with (I think) I'll be using Hornady 230 A tip.
Also be nice to find N570 at something other than the current ridiculously tear jerking price....
I needed .334 bushing for Lapua brass and 230 Hybrids. .335 hold was just a little light
Pls forgive my lack of knowledge... a friend writes me this about reloading 300 NM:
After you get the perfect powder weight and jump on a load, then you will have make up ten rounds with each bushing to see if your rifle prefers a certain "squeeze" around the bullet imparted from the neck's various 1/1000 inner diameter changes. And then, for my money, what is the point of going to that work and expense for that precision without also taking on "neck turning" as well. Unless you turn necks O.D. (outside diameter) also, the pressure around the circle will not be concentric anyway.
I had no idea reloading 300 NM was leaps more complex than 300 WM or 300 PRC... Seems like a lot more steps I'm not sure I should attempt at my experience level. Maybe I should reconsider and go with 338?
After you get the perfect powder weight and jump on a load, then you will have make up ten rounds with each bushing to see if your rifle prefers a certain "squeeze" around the bullet imparted from the neck's various 1/1000 inner diameter changes. And then, for my money, what is the point of going to that work and expense for that precision without also taking on "neck turning" as well. Unless you turn necks O.D. (outside diameter) also, the pressure around the circle will not be concentric anyway.
I had no idea reloading 300 NM was leaps more complex than 300 WM or 300 PRC... Seems like a lot more steps I'm not sure I should attempt at my experience level. Maybe I should reconsider and go with 338?
300NM Improved
335 neck bushing then used a 304 mandrel.
Now that brass is fireformed I’m loading up test loads with different mandrels from 21ST Century to see what neck tension it likes. I’m shooting 230 Berger’s
Parker
335 neck bushing then used a 304 mandrel.
Now that brass is fireformed I’m loading up test loads with different mandrels from 21ST Century to see what neck tension it likes. I’m shooting 230 Berger’s
Parker
It's not .300NM per se, but precision loading in general. Neck tension is important, but it often doesn't need to be tweaked to such extremes. A lot of folks have a few bushings to tweak neck tension, and that's enough. Personally, I've moved away from that and have one smaller bushing and then use incrementally sized neck mandrels to set the tension.
But generally, getting a good charge weight comes first, then tweak the group size with Seating Depth Adjustments, and then optionally tweak neck tension.
Ok so I went to do the neck sizing die and used a .336 bushing on brand new Lapua brass using 230g Berger OTM Tactical and the case got stuck. I drilled a hole through the open primer to get a hole big enough to use a modified screwdriver that was turned into a hooked pick and tried prying it out and broke the tool twice. Luckily, my dad’s a machinist and took it to work and got it out. Anyone know why this happened. Is it because I don’t have to anything to brand new, unfired, brass?
1. No, you definitely don’t have to size the necks down with unfired Lapua brass. Usually their neck tension is absurdly high and I have to use a mandrel to open up the necks (at least in other cartridges).
2. The above is not a reason for a case to get stuck. In fact, you should be able to size the neck down to the next size bullet without getting the case stuck in the die. What lube did you use? What die? How did you set it up? How did you decide on that size bushing?
