Redding Type S FL bushing help needed

[DamnDave]

I have the 334, 335 & 336 TN bushings for the Redding Type S FL dies in 308. Normally I use my 334 for PMC brass, 335 for Federal and 336 for my Magtech. I found a bunch of once fired PPU brass in my bin and am tumbling it now. I don't have any unfired rounds of it to measure, so is there another way to measure it to know which bushing I should use? I am pretty new to reloading so any info would be helpful.

Not sure if it matters, but they are being shot from a R700 SPS Varmint 308 1:12

 

[18Echo]

Re: Redding Type S FL bushing help needed

Once your brass is done tumbling measure the neck thickness, multiply by 2 + .308, then subtract .002 or .003 whatever you prefer.

ex. .012 neck x 2 = .024 +.308=.332 - .002(neck tension desired)= .330 bushing

Is this what you are looking for?

 

[DamnDave]

Re: Redding Type S FL bushing help needed

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 18Echo</div><div class="ubbcode-body">Once your brass is done tumbling measure the neck thickness, multiply by 2 + .308, then subtract .002 or .003 whatever you prefer.

ex. .012 neck x 2 = .024 +.308=.332 - .002(neck tension desired)= .330 bushing

Is this what you are looking for? </div></div>

That is exactly what I was looking for.

Thanks!

Hopefully I do not need to buy another bushing. Those badboys are starting to add up!

 

[ChrisGarrett]

Re: Redding Type S FL bushing help needed

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: AlliedArmory</div><div class="ubbcode-body">I have the 334, 335 & 336 TN bushings for the Redding Type S FL dies in 308. Normally I use my 334 for PMC brass, 335 for Federal and 336 for my Magtech. I found a bunch of once fired PPU brass in my bin and am tumbling it now. I don't have any unfired rounds of it to measure, so is there another way to measure it to know which bushing I should use? I am pretty new to reloading so any info would be helpful.

Not sure if it matters, but they are being shot from a R700 SPS Varmint 308 1:12 </div></div>

You need to measure the neck walls and double that average. Use a Ball Micro-meter, not a standard pair of calipers.

Then you pick a bushing and subtract the neck wall 'total' from the bushing size.

For your .336" bushing, it would be .336"-.029" (.0145" x 2, for example) to give you .307", or .001" of 'neck tension' for lack of a better word. You might get .001" of brass springback, but let's keep it simple. These are all approximations, anyhow.

If you want .002" of NT, then you would use your .335" bushing and so on and so forth. .335"-.029"= .306", or .002" once again, of NT.

You need to get an average of your cases' neck wall thicknesses to figure out where you're at. Measure in a couple of spots around the neck.

Chris

 

[mdmp5]

Re: Redding Type S FL bushing help needed

it is easier to just load a bullet into a sized piece of brass and seeing how much the neck expands. If it doesn't expand, you need a smaller bushing.

 

[Stone842]

Re: Redding Type S FL bushing help needed

Without a Ball Micrometer, you can't really measure the neck wall thickness directly.

This is how I do it with the regular micrometer:
1. Seat a .308 bullet into a dummy case (no primer or powder)
2. Measure the thickness at the end of the neck near the bullet.
3. Subtract .002" for a Bolt gun and .003" for a Gas gun. This is the bushing you need.

For example: with Fed brass you will get .338"-.002" (Bolt gun)=.336" bushing. This also means that the Fed brass has a 2 wall thickness of .338-.308=.030" or one wall thickness of .015"

I find that Win Brass to be thinner @ .025" for the 2 wall thickness.

Hope this helps

 

[remr5]

Re: Redding Type S FL bushing help needed

Hi why do you subtract .002 when Redding recomends .001?

 

[Stone842]

Re: Redding Type S FL bushing help needed

It's a little more Neck tension.
Whatever number you pick, .001 or .002, won't make much of a difference. Just be consistent.

 

[remr5]

Re: Redding Type S FL bushing help needed

Thank you.

 

[mdmp5]

Re: Redding Type S FL bushing help needed

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: remr5</div><div class="ubbcode-body">Hi why do you subtract .002 when Redding recomends .001? </div></div>

Redding was catering to the benchrest crowd; they believed that .002 was too much. I think that is nonsense. Use .002 because if you go with .001, there will always be that piece of brass that is slightly thinner, and the bullet will slide right out of the case. Happened to me a bunch of times. But I also have a bunch of different sized bushings in case it happens.