Re-size question

[Remmy700]

And please brother don't think I am being disrespectful of u or your method. We both obviously feel strongly on how we do our own thing and I respect that. That's what I love about this site can make u think outside your norm a little to learn new things, and for that thank u brother.

 

[Rich Coyle]

Mikecr,

Maybe I need to anneal the brass. I leave the die about .020" above lock down. I measure each case as it comes out of the die to verify headspace. If it's right, it's right. If it is a couple thou over I just size it again. If it is three or four thou too long I turn the die about 15 thou of rotation down. That usually give about .001" more bump.

 

[bigedp51]

Years ago I read about another chamber measuring method. It involved cutting a case in half and removing another 1/2 inch from the base end. You then epoxied a copper bore brush in the base that fits snugly into the upper half of the case.

After the epoxy has dried you push the upper part of the case partially over the copper bore brush. You then chamber the case and let the bolt face push the case sections together. You now have a case that is a snug fit to your chamber and then you measure with a Hornady gauge.

I personally think the primer method is the simplest way to find your chambers actual headspace length. The primer method dates back to the rimmed cartridge days and you added the primer protrusion to your rim thickness to get your headspace reading.

 

[Deputy819]

@bigedp51

I first ran across your method in the below listed post and it was one of those "A Ha" moments for me. Thank you!

https://www.longrangehunting.com/th...-headspace-measurement-on-fired-cases.210962/

 

[Mikecr]

My position on it is that you can use a Bigedp51 'poor man's Go-Gage', or an actual go-gage(as validated with a NoGo-Gage), but final setting of the sizing system & results will be directly influenced by fully fire-formed cases.
Otherwise, I think the best you can do is get close enough -to tweak from there.

 

[Remmy700]

Everyone is a winner here at LRH as long as it's 1/2 moa or better lol

 

[MNbogboy]

Agreeing with all here that setting bump can be a real pain. Here is my take.

When bumping with a body die (or full length) it is important to remember that you are moving brass almost the full length of the case. The neck & case shoulder move towards the bottle neck in the die and then the brass flows thru the shoulder and up the neck. Re-setting the die a thousandth or two at that point and resizing the same piece of brass often seems to have no effect on bumping the shoulder any more. "Springback" is working against you at this point because of the lack of the "fluid" motion (for a lack of a better term).
I have found that using a different piece of fired brass for each adjustment actually shows the move that was made.
I shoot for 1 to 1.5 thousandths.
The trial setup pieces of coarse are still wrong and still will be tight. I run them thru the new setting and load them up as foulers they will clear up on the next bump.
Once this bump is set it seems to hold well for at least 4 or 5 firings until I anneal. Even after annealing it rarely has required to be reset.
My .02,
Randy

 

[HobieH3]

Can someone recommend a good source to read about all this that's not too technical for a newbie? More of an explanation of principles that a how-to.

Either a book or a series of articles?
Is there a "Reloading for Dummies"?

 

[Remmy700]

Google Road to Precision. Very good multiple part series that covers some good topics and is very simplified

 

[feelinducky]

thanks for all the replies.

 

[300jcc]

OP - to be honest, everything you need is in this thread. Many have different methods. I measure every case every time - no exceptions. However, I don't even consider a bump until my bolt is too sticky. With Lapua brass, I can't honestly remember how many firings I can get (and I run max FOR MY PARTICULAR RIFLE most of the time). I know I can get 3 very easily, and I normally run twice fired brass for a match or a big hunt. Anyway, look at the illustration where I believe it shows the shoulder moving OUT during sizing. This is a fact, and I think it helps to understand that when you know you didn't even touch the shoulder when you pulled the handle and it's LONGER than when you started. If you'd rather just load and not know oodles of "theory", just buy the Hornady tool and measure each case, lube every single case the exact same, size, measure. But again, I cannot recommend the value of neck bushing dies more strongly. It makes your first several loadings very very easy. I also anneal, and I recommend it be done periodically - depending upon how often you FL resize.

 

[James D Crawford]

Good points, what u are talking about with your FL sizing die operation and how it stretches a case upward is basic reloading principles. Your method seems sound but i over analyze everything when in fact it's very simple. Saying u have a perfectly sound case, meaning exact shoulder angle (which in some brass is not the case when new) also assuming u have a primer that is absolutly flat (not even small amount of cratering) then I would say this idea would be pretty sound. But honestly there is not better example of chamber dimensions than brass that has been truly fire formed. If a new piece of brass is used with primer method and even a slight variance in shoulder angle when compared to the actual chamber that datum line that is used with the headspace gauge kit is null and void when that brass becomes actually fire formed. Maybe only slightly but we are playing a game of small numbers. I am going to try your method just because I like to test stuff lol!!!

Concisely put.

 

[Mikecr]

I suppose FL sizing is easily assumed, but a lot of folks don't. I don't ever (I know, that's another thread).
I do shoulder bumping with bump dies, neck sizing with neck dies, neck expansion with expansion dies, and bullet seating with seating dies. with this, many of the FL factors declared as absolutes are not -for me and for others.

There are people here doing anything you can imagine. They figure out a way

 

[James D Crawford]

OP - to be honest, everything you need is in this thread. Many have different methods. I measure every case every time - no exceptions. However, I don't even consider a bump until my bolt is too sticky. With Lapua brass, I can't honestly remember how many firings I can get (and I run max FOR MY PARTICULAR RIFLE most of the time). I know I can get 3 very easily, and I normally run twice fired brass for a match or a big hunt. Anyway, look at the illustration where I believe it shows the shoulder moving OUT during sizing. This is a fact, and I think it helps to understand that when you know you didn't even touch the shoulder when you pulled the handle and it's LONGER than when you started. If you'd rather just load and not know oodles of "theory", just buy the Hornady tool and measure each case, lube every single case the exact same, size, measure. But again, I cannot recommend the value of neck bushing dies more strongly. It makes your first several loadings very very easy. I also anneal, and I recommend it be done periodically - depending upon how often you FL resize.

And actual brass temper will affect all pressure movements, and spring back! Good thread!