Please help me understand.

[scorpion168]

I thought I was on a roll loading my .308, but now my inquisitively detailed cabinet-making side is creeping in. I'm trying to bump the shoulder back .002 on my once fired Lapua brass. My Redding type S neck sizer with .337 does not seem to be doing this. Is this the task of the FL sizer? I thought the FL sizer "undoes" what being fire-formed does. Sorry if this sounds so elementary. I'm probably one small bit of info from making this thing purr like a well oiled machine.

 

[bigedp51]

I'm 64 and have been reloading for over 46 years, and I'm going to answer you question by posting an answer by someone younger BUT who has far more experience on the subject than I do. I will also say I believe in the rat turd method described below by the Late Jim Hull. Also please note the answer is given by Kevin Thomas of Team Lapua USA..............

 

[Graham]

Please help me understand.

That post is not on point: Kevin's answer addresses whether neck sizing extends the life of brass and whether FL sizing produces less accurate ammo.

Setting aside for a moment that the OP asked whether bumping the shoulder is the task of the FL sizer die (yes it is, one of them), his issue appears to be that he is trying to bump the shoulder using a neck sizing die.

He needs to measure the case head to datum length and use a die that bumps the shoulder of the case.

 

[No1]

I too was unable to move the shoulder with the neck bushing die, despite reading many places on the infallible internet that it's commonly done. I switched to the FL bushing die type S. I was tempted to just cut the die down a little but decided I should run a FL die anyway.

 

[scorpion168]

Ok. We're getting somewhere. I still need to know if FL sizing does away with fire forming. Also, a lot of chatter I hear states that the better a round fits my chamber, the more accurate it is. I'm not trying to deny any answers, I'm just still very curious and love to gather info. Naturally, the more info that runs along the same lines seem to be more accurate.
So, why neck size, and why FL size?

 

[Graham]

Please help me understand.

Fire forming is a process by which brass is expanded and the shoulder of the case formed to a new dimension under pressure in a chamber.

FL sizing is the process by which the body of the brass case is returned to standard specifications.

So, no, FL sizing does not "do away with" fire forming. They are different processes.

 

[scorpion168]

Thanks Graham. You left out neck sizing. Why neck size instead of full length size? I guess my main thought is why not shoot with fire-formed brass, and how would you size that brass? Please bear with me, we are getting somewhere.

 

[Graham]

Please help me understand.

Fire forming brass makes a new caliber. That's not what you are doing.

Like Kevin said, FL every time. Because we are not Benchrest shooters who use the same 35 pieces of brass, control every custom dimension of those 35 pieces in a custom chamber and care nothing about reliability in adverse conditions.

In our game you couldn't shoot the difference in accuracy between a FL sized case and a neck sized case even if there was a difference in your rifle.

 

[Asperly Aimless]

Neck sizing dies are for sizing the neck. Get a body die from redding or get a FL sizing die to bump the shoulder.

 

[scorpion168]

Uh huh... I'm soaking it up. So I should focus on my Forster FL die now. Thanks for your patience and time, Graham. Your response is why I come here to get educated. Any tips on using my Forster die?

 

[Graham]

Please help me understand.

Get a tool to measure the amount of shoulder bump. Don't just screw it down all the way to the shellholder and start shucking cases.

 

[Rattler56]

Graham is 100% on point.

 

[Asperly Aimless]

Get a tool to measure the amount of shoulder bump. Don't just screw it down all the way to the shellholder and start shucking cases.

Amen!

 

[scorpion168]

That I understand. Should I measure from base to ogive, and set the die accordingly?

 

[scorpion168]

I have a precision mic set and a modified case. This should do it, yes?

 

[Asperly Aimless]

No. That is used when measuring loaded ammo to ensure consistent jam or jump.

You will measure from base to shoulder using a comparator body with a bump gauge insert.

 

[scorpion168]

Ugh! I was so close! Lol
Should I set my die up "loosely" and check in my chamber till it starts it get tight?

 

[Asperly Aimless]

You can use your chamber to set up your sizing die.

 

[Graham]

Please help me understand.

No, you should measure the amount of shoulder bump that you want, using a fired case, and set your die to produce that amount.

 

[Asperly Aimless]

It is better to use the correct tools to measure and get a tangible result, but when lacking the correct measuring stuff you can jut use your chamber. You won't know exactly how much you bumped the shoulder back though.

 

[Graham]

Please help me understand.

You won't know anything except that the case fits in the chamber, which a fired case will do anyway without resizing it. So using your chamber will tell you nothing about shoulder bump.

 

[HodgdonExtreme]

I have a precision mic set and a modified case. This should do it, yes?

Yes. The precision mic is the tool for the job.

First measure 2 or 3 DEPRIMED, fired cases and note the measurement. Then adjust your sizer so that sized brass measures ~.002" less than deprimed fired brass.

A good die starting point is to raise ram, screw die in until it *just* kisses the shell holder. Adjust up/down as necessary.

 

[Graham]

You must measure to the datum line of the case.

 

[scorpion168]

Thanks. I'm on it.

 

[Asperly Aimless]

Here is a light bit of reading to add to your tool box.

Setting up a Full Length Sizing Die |

 

[wxl]

What rifle? I bump ~0.001" for bolt gun but go 0.003-0.004" for semi autos (AR10, M1A,...). Using precision tools to measure shoulder bump is best. A crude method for bolt gun is to chamber brass, if bolt closes reasonably easy, you should be GTG. After multiple firings, bolt may start to get tight, screw FL die down ~1/8 turn or until bolt closes easily.

Neck sizing only is pretty old school and not practiced as much as before. For hunting rounds I prefer bumping 0.001-0.002" to make sure I can chamber my ammo. Real pisser when you cannot chamber a round and lose opportunity to take game.

 

[duhblow7]

I found this guide/sticky to be very helpful.

http://www.snipershide.com/shooting...and-loading-long-range-1-brass-case-prep.html

It shows which tools are needed and how to use them. Very detailed and got me on point.

 

[scorpion168]

Thanks. I am loading for Savage bolt 308. Anybody have a good video I could watch for instruction?
Also, my Gempro 250 has started acting up after about a year. It's not accurate and will not tare out. I liked it, wish it would last. I like a digital scale. Should I try another?

 

[Victor N TN]

You must measure to the datum line of the case.

Get the Stony Point (now Hornady) tool for that job specifically. If you don't already have a 6" dial caliper a $25 one. It'll work fine, if that's all you can afford.

 

[Victor N TN]

Also, my Gempro 250 has started acting up after about a year. It's not accurate and will not tare out. I liked it, wish it would last. I like a digital scale. Should I try another?

Something I read says that brand has a life time warranty. Check into that before spending money on something else.