Sizing Brass

[Brian o 23]

Can someone please help me understand the method of resizing brass Right now I take my 2nd fired brass measure it with my redding instant indicator and headspace and compared to the redding case provided with the indicator, and from my measuremeant I bump my brass back .002"
I found this video on youtube and wondered if not bumping the shoulder would work.
Please help.
Thanks

STOP BUMP SIZING! - How To Properly Setup Full Length Die For Precision Bolt Action - Feel Method

 

[47guy]

heres david tubbs on sizing....ive also heard him say he sizes his brass UP TO .005



personally i like to feel a slight resistance at the bottom of the bolt close in my prone gun...in my tactical gun i do not want any resistance...i want it to close and open FAST and EASILY.

 

[XLR308]

I set mine up for .0015 - .002" shoulder bump.
Don't over think it if your bolt opens easy with no resistance on your fisred brass it should be close to .00 - .001" and go from there.

 

[47guy]

Don't over think it.

THIS^^

 

[supercorndogs]

Can someone please help me understand the method of resizing brass Right now I take my 2nd fired brass measure it with my redding instant indicator and headspace and compared to the redding case provided with the indicator, and from my measuremeant I bump my brass back .002"
I found this video on youtube and wondered if not bumping the shoulder would work.
Please help.
Thanks

STOP BUMP SIZING! - How To Properly Setup Full Length Die For Precision Bolt Action - Feel Method

I want him to emphasizes and illustrate better results on target.

Moving the shoulder back .001 at a time setting up a die is not work hardening the brass in a significant way.

To say bumping shoulders back .001-.002 is wrong, is retarded. It would be the same as saying his method is wrong. Its different than mine, and I bet you dollars to donuts he can't shoot the difference between the two methods.

Personally, I want zero resistance closing the bolt. I go through my once fired until I find a long one, then i check it vs the chamber. If i feel resistance closing the bolt, there is my piece to set up the die with. Then I move the die down until I achieve .001-.004 and check to make sure the brass chambers easily.

Remember to de-cap your brass before measuring. A proud spot on a primer can have you chasing your tail all day.

I hate galled bolt lugs.

 

[Ryridesmotox]

Man, when I was first getting into precision reloading I was going nuts trying to quantify what is better or worse for sizing brass. I'm not saying my method is right or wrong. But I got a lee 3 die set. I would deprime and FL size every round fired. I had no fucking clue at the time that it wouldnt shoot .5moa groups... because I was shooting .5moa groups. It's like a bee in flight, people think it shouldn't be possible, but the bee doesnt give a damn what people think.

My advice would be to start with a FL size, use plenty of lube and get to the point where you are certain that the groups are as small as they get. Consistent setup and cartridge prep is the name of the game here. You can ignore like 98% of the bullshit on youtube. Dies that are properly set up, working correctly, and operated well, will produce ammo more precise than most shooters are. Once you have created a load and are getting groups as small as possible then start changing little things. I started experimenting with a Lee collet die a few months ago with pretty good results. Still trying to see if it really makes a difference. But everyone has their own way dude.

Pick something that works in your budget and roll with that. It's pretty simple when you dont overthink it.

 

[spife7980]

Right now I take my 2nd fired brass measure it with my redding instant indicator and headspace and compared to the redding case provided with the indicator, and from my measuremeant I bump my brass back .002"

Dont do that, do it from your fired cases. You have no idea how that redding provided case fits in your chamber or compares to your brass.

Virgin>Fired>Sized.
Virgin>Fired only tells you the initial stretch, thats interesting but ultimately not super beneficial unless its an extreme.
Fired>Sized tells you how much head space clearance you are creating between the brass and the chamber. Sure, 1x fired may not be a perfect cast of the chamber but as xlr308 said, use some common sense and only bump it down whats necessary to clear the chamber easily. No one likes fighting the bolt because they are using their chamber as a sizing die to force the ammo to function. .001-.002 is about the average sizing it takes to achieve chambering without struggling with it.



I like how the guy tries to spin the benefits of minimally bumping the shoulders back as negatives.
"They bump it back just enough to clear the chamber freely. I prefer to add difficulty to my bolt close."
His reasons for what he does are the exact reasons that we dont do what he is saying.

 

[918v]

Plus, he’s wearing out his bolt lugs.

 

[TxWelder35]

That redding case it came with should be the SAMMI minimum chamber length. It's just a point to reference off of

 

[Changed]

He goes on to claim that it is impossible to hold a tight enough tolerance to size exactly .002. I had to laugh at that wisdom. Especially considering the fact he was using harbor freight's finest digital caliper. Many people have confronted him and told him that he was bumping his shoulders. He won't have it. He's also claiming that the lateral movement in the chamber is a result of trying to bump .002. Look at the numbers he got from testing how accurate he could hold a tolerance. He had errors in the 10ths.

Actually, if you look at the video in slow-motion, you can see his sizing die flexing up when he runs the ram home. I'm guessing that's because he used the Hornady QD system. Either way, he is inducing error and then saying it is impossible to hold a tolerance.

 

[Brian o 23]

Thanks all for the reply

 

[Sheldon N]

I found this video on youtube and wondered if not bumping the shoulder would work.

Ignore what that guy says entirely.

His position basically boils down to "I like to under bump my shoulders because it's more accurate". But it's not.

Here's instructions from one of the top benchrest gunsmiths in the country on how to size brass. This approach is what is being used by pretty much all of the world record benchrest shooters. AND it's the approach being used by pretty much all of the top PRS shooters. AND it's the approach being used by pretty much all of the top F-Class shooters.

Full length size your brass using measurements and checking chamber feel, until you get smooth function and easy chambering, without oversizing to the point where you would induce case stretch.

Note that he has stripped the bolt down when he is checking chamber feel. No ejector plunger, no firing pin spring that interfere with your ability to feel the brass in the chamber.

 

[Brian o 23]

Ignore what that guy says entirely.

His position basically boils down to "I like to under bump my shoulders because it's more accurate". But it's not.

Here's instructions from one of the top benchrest gunsmiths in the country on how to size brass. This approach is what is being used by pretty much all of the world record benchrest shooters. AND it's the approach being used by pretty much all of the top PRS shooters. AND it's the approach being used by pretty much all of the top F-Class shooters.

Full length size your brass using measurements and checking chamber feel, until you get smooth function and easy chambering, without oversizing to the point where you would induce case stretch.

Note that he has stripped the bolt down when he is checking chamber feel. No ejector plunger, no firing pin spring that interfere with your ability to feel the brass in the chamber.

Thank you, that is how i"m bumpimg back my Tikka T3x custom barrel build after getting the bolt to close freely it's .002" under the fired case size.

 

[XLR308]

The chamber that Kelblys cut for my 65 Creedmoor is .002" over new Lapua brass out of the box. I specified I would be using Lapua brass exclusively in my notes when I sent my barrel to them after we had discussed free bore length and the bullets I planned on running.
It made it super easy setting up my new dies since it was my first cartridge in 65 anything and the new brass I have been using as well for load development since it is so close to chamber dimensions it has been easy to find various loads with several different powders and bullets that easily shoot in the 1/2 MOA range and under.
Most factory rifles I have owned I wouldn't even attempt to work up a load on new brass but have had a couple of exceptions.

 

[Brian o 23]

What I was going to do is take a second fire brass and use a FL body die and bump the shoulder 0.000" and see how it fit in my chamber and slowly lower the fl body die till I had a smooth bolt closure and check to see how far I bump the shoulder.
Once I have the shoulder where I want it I plan to use the Lee collet neck die to set the neck tension.
Any thoughts on this process?

 

[XLR308]

What I was going to do is take a second fire brass and use a FL body die and bump the shoulder 0.000" and see how it fit in my chamber and slowly lower the fl body die till I had a smooth bolt closure and check to see how far I bump the shoulder.
Once I have the shoulder where I want it I plan to use the Lee collet neck die to set the neck tension.
Any thoughts on this process?

If you are that curious to know exactly were your brass makes contact on the shoulder in the chamber and find exactly your measurement that your bolt closes without restistence try this.
With the die intentionally set to far out not a bunch but roughly .010" the brass will grow slightly before contact is made with the shoulder. You can work your way down from there checking it in your action.

 

[Brian o 23]

Cool, I start there my redding instant indicator will give me the + measurement and I can check as I go. Thanks

 

[Sheldon N]

Any thoughts on this process?

I'd add to check your other dimensions as you size the brass, shoulder diameter, base diameter etc to make sure there is clearance in those areas too and you aren't getting resistance from some other point besides the headspace dimension.

Possible that you could feel a bit of resistance from the neck diameter, depending on how much springback you have, since you aren't sizing the neck until later in the process.

 

[Brian o 23]

Very

I'd add to check your other dimensions as you size the brass, shoulder diameter, base diameter etc to make sure there is clearance in those areas too and you aren't getting resistance from some other point besides the headspace dimension.

Possible that you could feel a bit of resistance from the neck diameter, depending on how much springback you have, since you aren't sizing the neck until later in the process.

Very good.

I was thinking of purchasing the Whidden Bushing Full Lenght Die set for .308 any thoughts on these dies?