redding s type bushing resizer

Jrb572

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Re: redding s type bushing resizer

It's on reddings site. If I remember correctly measure a loaded round and subtract .002. Not positive on the .002. But it's on there site
 

Subxero

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Re: redding s type bushing resizer

^ this, (.002 is accepted by most as minimal amount of sizing for minimal neck tension) You can always go more, .003, and .004 is acceptable. If you are not crimping hunting loads, greater than .002 might be wise.

another method is to take caliber, example, .308, add at least .015 (broadly accepted min value of neck thickness for factory chambers) x 2 (there are two sides of the case) .308 + .030 = .338

this is best for general estimate, If you turn your necks, and or other rifle and brass variables can change this.

If you feel .338 is too loose (not enough neck tension on bullet) you can always go down .001 or .002 to a .337, or .336

I use a .338 on my 300 Rum, it works great

again there are more precise ways of getting it just right, measuring case neck thickness, measuring neck diameter of fired round and plug those numbers into an equation. {(thickness of brass of case neck x 2) + bullet diameter} = x then Diameter of your fired case from your rifle - x = y, diameter of fired case - (y + your desired neck tension) = bushing

example
thickness of brass at neck measured .016 x 2 = .032
.032 + bullet diameter .308 = .340

diameter of neck of fired case = .343 - .340 = .003

diameter of neck of fired case .343 - [(.003 + desired neck tension .002 in this instance so (.003 + .002 = .005)] then .343 - .005 = .338 that would be my bushing size

hmmm does that make sense??? i always hated math, sure there was a better way to do that...... oh well hopefully i helped and did not hurt
 

Deadshot2

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Re: redding s type bushing resizer

If you are using a bushing die to neck size, it's imperative to make sure neck thickness is the same for all cases in the batch or be prepared to change bushings for each case sized.

Neck turning is almost a requirement when using this sizing method unless you want to use an expander which pretty much defeats the benefit of the bushing die to begin with.
 

MitchAlsup

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Re: redding s type bushing resizer

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Duffy1298</div><div class="ubbcode-body">how do you know what bushings to get? </div></div>

You measure stuff, and then fit the measurements to the application.

For serious benchrest where the cartrige suffers no abuse from reload stand to the final firing position, you can get away with 0.000 sizing. These applications use fitted necks.

For less serious benchrest, where the cartriage suffers no abuse and fitted necks are not in use, 0.0005 is fine.

For bolt action tactical applications where the cartriage must suffer some mild abuse, 0.002 is the rule.

For semiatuo cycling, where the cartriage must deal with the violent action of the action cycling and the banging around of the magazine, 0.003 is the rule.

If you use more than 0.003 of tension, the neck of the case will expand and give no more tension than 0.003 (would have given) anyway.

So, now that we have appliation matched to neck tension. We start measuring stuff. Measure the size of the bullet (shuold be 0.308). Measure the case neck thickness (should be in the 0.012-0.016 range).

Given the neck thickness and the bullet diameter, we find the loaded diameter as: 2*nt+bd = ld

Now the bushing selection is simply: ld-nt (from the above table).

Alternately, one can stick a measured bullet in a sized neck and simply measure the loaded diameter directly. Then subtract from this loaded diameter the neck tension from the above table.
 

gau17

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Re: redding s type bushing resizer

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Jrb572</div><div class="ubbcode-body">It's on reddings site. If I remember correctly measure a loaded round and subtract .002. Not positive on the .002. But it's on there site </div></div>

They have changed it to .001

From Redding site:

"The easiest way to determine the proper diameter bushing is to measure the neck diameter of several loaded or dummy cartridges with an accurate micrometer. (These dummy cartridges can be loaded with your old set of dies or a borrowed set.) Then, simply subtract 0.001" from the cartridge that had the smallest average measurement. This will allow for a slight amount of spring back and create a proper press fit for the bullet.

Another method of determining bushing size, is to measure the neck wall thickness of the cartridge cases with a ball type or tubing micrometer. Double this measurement and add the bullet diameter to calculate the neck diameter of a loaded cartridge. As above, subtract 0.001" from this figure to determine bushing size. This method is the least desirable of the two, as a ball micrometer is fairly expensive and more difficult to read consistently than a conventional micrometer."
 

JByrd

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Re: redding s type bushing resizer

best way is to size some of your brass with regular dies, the cheap crap dies regular people use way over size the neck. now seat a bullet take calipers and measure neck od. then subtract .001 thats your bushing size

ex.

loaded neck .335-.001= .334 bushing so get the .334

if your getting the ti ni coated bushings the coating is actually gonna give you .0005-.001 less than what the bushing is labeled b/c after all its just a regular .334 bushing with a coating

your brass is gonna vary a lil here and there in lots so if your gonna run this gun do your self a favor

if .335 was you loaded neck...get the .333,.334,.335,

in a bolt gun stay around .002 getting much over that is gonna start killin your accuracy.

and as stated before redding does have the od-.001 info on their website , dig a lil
 

arnie19

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Re: redding s type bushing resizer

I have bushing dies but have been liking the Lee collet dies the more i use them.Arnie
 

majohnson2

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Re: redding s type bushing resizer

Take a fired case and measure the o.d. of the neck, this will also give you the i.d. of your chamber. From there subtract the tension value you want. Your only trying to get enough neck tension to stabilize the bullet in the mouth of the case and have the round chamber.
 

FLIGHT762

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Re: redding s type bushing resizer

I used Redding's recommended method of measuring a loaded cartridge neck and subtracting .001".

For .308 Winchester, I use a .337" for Federal brass. .333" for Hornady brass, .331" for Winchester brass and a .335" for Remington brass. I bought a spare in .329". Don't use it too often, but it's there.

This is for a bolt gun. Works out fine for me. I have enough bushings to tweak for adding tension for an autoloader.
 

Cacciatore

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Re: redding s type bushing resizer

I just bought .332 & .333 for my .308. I measured the OD of the neck of a loaded cartridge, just below the mouth. I measured 15 pieces to get a good idea and took the average. I subtracted .001 off the average and ordered 2 to play around with.
 

groovinpickle

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Re: redding s type bushing resizer

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: arnie19</div><div class="ubbcode-body">I have bushing dies but have been liking the Lee collet dies the more i use them.Arnie </div></div>
They're much less sexy, but I agree about the Lee collet neck die. I resisted getting one for a long time but finally did, and the decrease in neck runout is significant.
 

BullzeyeNJ

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    Re: redding s type bushing resizer

    Yeah, and once you get the formula down you will find yourself buying lots of redding bushings. The coated gold ones are about $25 a piece. A little smoother then the steel ones but twice the price.

    I probably have $400 in bushings alone. Oh well, it's like a socket wrench set, if you don't have the tool when you need it then you can't finish the task at hand.
     

    Deadshot2

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    Re: redding s type bushing resizer

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: groovinpickle</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: arnie19</div><div class="ubbcode-body">I have bushing dies but have been liking the Lee collet dies the more i use them.Arnie </div></div>
    They're much less sexy, but I agree about the Lee collet neck die. I resisted getting one for a long time but finally did, and the decrease in neck runout is significant. </div></div>

    Got to admit that these collet dies are pretty darn good. I've experimented with mine and found that it works best if I follow the sizing process with a Sinclair expander die. Where the Lee gave me .306" +/- .001", I now get a perfect .306" measurement on all finished cases.

    Hard to make up my mind which is best although the Forster bushing die also bumps the shoulder and with the Lee Collet, after a few firings the bolt can get difficult to close.
     

    groovinpickle

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    Re: redding s type bushing resizer

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Deadshot2</div><div class="ubbcode-body">Hard to make up my mind which is best although the Forster bushing die also bumps the shoulder and with the Lee Collet, after a few firings the bolt can get difficult to close. </div></div>
    Yep, and I FL size each time, but in a case like mine when I have to reduce the neck in size by ~0.006" it takes two runs through the Redding die. I use an oversized bushing that doesn't size the neck in my Type S to bump the shoulder, then run it through the Lee collet neck die, so no extra work for me.

    I'm still hanging on to my Redding, but even using two-step sizing and no expander, the Lee is the clear winner for me in terms of concentricity.
     

    Manimal

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    Re: redding s type bushing resizer

    When measuring a loaded round, do we measure a round that WE have loaded? Reason I ask, how does a beginner who has never reloaded measure brass they have loaded? See what I mean? This measurement may be different with each brand of brass, correct? So one bushing for each brand of brass, i.e .336 for Lapua and .333 for Winchester?