Nk Sizing
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Re: Nk Sizing
I'm new to the neck sizing approach and found that my .260 brass ends up 0.002 smaller than what the bushing is. I later found that this is due to the neck being sized from 0.296 to 0.289. Now I have to decide if I want to buy another bushing to do it in two steps, or just use the neck expander to open it up.
I'm new to the neck sizing approach and found that my .260 brass ends up 0.002 smaller than what the bushing is. I later found that this is due to the neck being sized from 0.296 to 0.289. Now I have to decide if I want to buy another bushing to do it in two steps, or just use the neck expander to open it up.
Re: Nk Sizing
Mine is an even larger gap between fired and busing size. I do it all in one step and my ammo produces good accuracy. I can't speak for what it does to brass longevity though...
Mine is an even larger gap between fired and busing size. I do it all in one step and my ammo produces good accuracy. I can't speak for what it does to brass longevity though...
Re: Nk Sizing
My load round measure .338"
My brass thickness measure Mitutoyo Ball Micro Meter was 0.015"
(0.015 + 0.015) + .308 = .338"
0.001 for Brass spring back & 0.001 for nk tension
So, my prefer nk was .336"
So, which bushing should I use in case that I prefer .336" nk?
My load round measure .338"
My brass thickness measure Mitutoyo Ball Micro Meter was 0.015"
(0.015 + 0.015) + .308 = .338"
0.001 for Brass spring back & 0.001 for nk tension
So, my prefer nk was .336"
So, which bushing should I use in case that I prefer .336" nk?
Re: Nk Sizing
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Golfy Sniper</div><div class="ubbcode-body">
My load round measure .338"
My brass thickness measure Mitutoyo Ball Micro Meter was 0.015"
(0.015 + 0.015) + .308 = .338"
0.001 for Brass spring back & 0.001 for nk tension
So, my prefer nk was .336"
So, which bushing should I use in case that I prefer .336" nk? </div></div>
Yes, the equation is correct. But Redding started to recommend .001" for bolt gun and .002-.003 for semi-auto.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Golfy Sniper</div><div class="ubbcode-body">
My load round measure .338"
My brass thickness measure Mitutoyo Ball Micro Meter was 0.015"
(0.015 + 0.015) + .308 = .338"
0.001 for Brass spring back & 0.001 for nk tension
So, my prefer nk was .336"
So, which bushing should I use in case that I prefer .336" nk? </div></div>
Yes, the equation is correct. But Redding started to recommend .001" for bolt gun and .002-.003 for semi-auto.
Re: Nk Sizing
Personally, I prefer .003 for my own .308win reload. Because by size .001" the bullet is not tightly hold by the case mouth, and I feel I can easily pull the bullet by hand. But they do shoot good. Just personal preference.
Once your case is being used over and over, you started to find the gap between your neck size and bushing used. That's why a lot of people recommend anneal your case every 3-4 reloads.
Personally, I prefer .003 for my own .308win reload. Because by size .001" the bullet is not tightly hold by the case mouth, and I feel I can easily pull the bullet by hand. But they do shoot good. Just personal preference.
Once your case is being used over and over, you started to find the gap between your neck size and bushing used. That's why a lot of people recommend anneal your case every 3-4 reloads.
Re: Nk Sizing
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Golfy Sniper</div><div class="ubbcode-body">
My load round measure .338"
My brass thickness measure Mitutoyo Ball Micro Meter was 0.015"
(0.015 + 0.015) + .308 = .338"
0.001 for Brass spring back & 0.001 for nk tension
So, my prefer nk was .336"
So, which bushing should I use in case that I prefer .336" nk? </div></div>
One other piece of information is needed. What is the outside diameter of the neck on the brass after firing in your rifle? This will determine if you need to do the neck sizing in two steps or can do it in one step.
I just re-read the entire thread and it sounds like you'll need to do the neck resizing in two steps.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Golfy Sniper</div><div class="ubbcode-body">
My load round measure .338"
My brass thickness measure Mitutoyo Ball Micro Meter was 0.015"
(0.015 + 0.015) + .308 = .338"
0.001 for Brass spring back & 0.001 for nk tension
So, my prefer nk was .336"
So, which bushing should I use in case that I prefer .336" nk? </div></div>
One other piece of information is needed. What is the outside diameter of the neck on the brass after firing in your rifle? This will determine if you need to do the neck sizing in two steps or can do it in one step.
I just re-read the entire thread and it sounds like you'll need to do the neck resizing in two steps.
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