Adjusting FL die for minimal brass movement

[mardanlin]

I've read about people adjusting their FL die to only set the shoulder back a small amount which they claim leads to longer case life.

How exactly do I go about setting these adjustments? Does turning the knob at the top clockwise increase or decrease the amount the shoulder is set back, or does this only control the decapping pin? Also, should I just adjust it several times and measure the cases each time to see when it's resized properly?

I am using Lee 3-die set and referring to a 30-06 if that matters.

[chris in va]

Semiauto or bolt?

[dmazur]

Here's a link to something which I believe should answer your question -

http://reloadingtips.com/how_to/sizi...adjustment.htm

This is the "use the rifle's chamber as a gauge" method and does not require the purchase of what is referred to as a cartridge headspace gauge, such as the ones made by Wilson.

While this article doesn't cover semi-auto vs. bolt-action, I believe the idea is to treat semi-autos as being in the "must fit other rifles" category and not try for neck-only resizing adjustments with a FL die.

The reason is that semi-autos do not have the camming power of a bolt-action and the cartridge must fit without effort if you want reliable chambering. There can also be safety considerations. (Look up "slamfire")

If you have a semi-auto .30-06, you probably should get a Wilson-type gauge to help set up the resizing die for a minimum head to shoulder length in the resized cartridge.

Brass life just isn't as long with semi-autos as with bolt-actions...

[Bart B.]

That knob only adjusts the height of the decapping pin. You need to turn the die in the press to change its height relative to the shell holder's bottom where the case head is when sizing the case.

'Tis my opinion that best accuracy and case life for bolt action rifles using bottleneck rimless or belted cases happens when the case fits between the bolt face and chamber shoulder with minimal clearance. No pressure on the bolt handle's needed to close the bolt. To do that means the full length sizing die has to be set in the press such that fired case shoudlers are set back by the die no more than a thousandth inch or two.

This can be done without costly tools and reasonable mechanical aptitude. You'll need to know how much the die moves up and down in the press in small increments, 1/1000th inch or thereabouts so your adjustments can be made precisely enough to be the best possible. Two methods exist.

One is just turning the die 1/16th, 1/32nd turn as best you can for each test of sizing the case, then chambering it to feel how it fits. If the bolt doesn't close, then screw the die down a bit and try again with another case. This is rather crude and often ends up with the die set too low in the press sizing the case too much. That shortens case life and leads to head separation after several full length sizing cycles on a give case when its shoulder's set back too much.

Another is being able to turn the lock ring on the die to change its height in the press by 1/1000th inch. That involves turning the die in its lock ring so that a mark on the die moves about 1/10th inch around the lock ring. As the die moves about .072" up or down per turn in the press, 1/72nd of a full turn moves the die .001" up or down. 1/8th of a turn moves the die about .009", 1/16th turn is half that; .0045" or .004" is close enough. Download this link for a set of lables to print on sticky back paper to cut out and stick put on your die's lock ring:

http://s860.photobucket.com/user/jep...ent-1.jpg.html

Follow their directions to adjust your die which is essentially as follows.

Set the die in the press with the ram all the way up such that it just touches the shell holder. Clean, lube then full length size a case. Strip the bolt so it'll close without interference on that sized case. Chamber that case then close the bolt on it gently. If the bolt doesn't close, loosen the die and its lock ring, set the die .001" or .002" deeper in the lock ring depending on which label you used. Tighten the lock ring, set the die back in the press, and repeat with another fired case. Do this until the bolt easily closes on a sized case, then the die's set to minimally full length size your fired cases for that rifle's chamber.

For semiautos, the fired case shoulder should be set back about .003" to .004" inches for reliable extracting, but case life is limited to 4 or 5 reloads per case. Bolt action rifles get by easily with only .001" or .002" setback and have much longer case life.

It's been my experience (and that of many others) that best accuracy happens when the bolt doesn't bind at all on chambering a round. Especially when factory bolt faces are not perfectly square with the chamber axis. Case heads get a tiny bit out of square when fired in such rifles. When reloaded and chambered, their high points typically are not opposite each other when that case was first fired, so there's a little bit of binding that happens. That makes the bolt head position different places around the case head. And that makes the rifle barrel whip differently from shot to shot due to the force of the case head slamming against the bolt face is at different places around the bore and case axis. If it's well centered all the time, best accuracy is at hand. The difference is small, but can be seen at best accuracy levels.

[mardanlin]

Thanks for all the information! It is a semi auto also, my trusty M1

[F. Guffey]

This can be done without costly tools and reasonable mechanical aptitude. You'll need to know how much the die moves up and down in the press in small increments, 1/1000th inch or thereabouts so your adjustments can be made precisely enough to be the best possible. Two methods exist.

Then there are Skip's shims, in my opinion, an awkward way to use shims. instead of making adjustments off of the shell holder the die is removed and shims added, or subtracted. Again, verify, when adding Skip' shims verify, then the question, if a reloader is going to verify an adjustment after adding/subtracting Skip's shims, why not go straight to the verifying tool, the feeler gage?

F. Guffey

[F. Guffey]

That knob only adjusts the height of the de-capping pin. You need to turn the die in the press to change its height relative to the shell holder's bottom where the case head is when sizing the case.

'Tis my opinion that best accuracy and case life for bolt action rifles using bottleneck rimless or belted cases happens when the case fits between the bolt face and chamber shoulder with minimal clearance. No pressure on the bolt handle's needed to close the bolt. To do that means the full length sizing die has to be set in the press such that fired case shoulders are set back by the die no more than a thousandth inch or two.

This can be done without costly tools and reasonable mechanical aptitude. You'll need to know how much the die moves up and down in the press in small increments, 1/1000th inch or thereabouts so your adjustments can be made precisely enough to be the best possible. Two methods exist.

One is just turning the die 1/16th, 1/32nd turn as best you can for each test of sizing the case, then chambering it to feel how it fits. If the bolt doesn't close, then screw the die down a bit and try again with another case. This is rather crude and often ends up with the die set too low in the press sizing the case too much. That shortens case life and leads to head separation after several full length sizing cycles on a give case when its shoulder's set back too much.

Another is being able to turn the lock ring on the die to change its height in the press by 1/1000th inch. That involves turning the die in its lock ring so that a mark on the die moves about 1/10th inch around the lock ring. As the die moves about .072" up or down per turn in the press, 1/72nd of a full turn moves the die .001" up or down. 1/8th of a turn moves the die about .009", 1/16th turn is half that; .0045" or .004" is close enough. Download this link for a set of labels to print on sticky back paper to cut out and stick put on your die's lock ring:

http://s860.photobucket.com/user/jep...ent-1.jpg.html

Or,

Use the companion tool to the press, the feeler gage. A humble and most modest tool. The feeler gage is a transfer, the feeler gage is a standard, and! It can be used to verify the fractional turn in degrees and then converted to thousandths. A reloader that advances to verifying can skip the paste on indexes, just simply go straight to verifying.

Then there is Redding, they make shell holders that increase the deck height of the shell holder, the competition shell holders are designed to increase the sizing ability of the die by .010", I know, if they are that wonderful why don't I use them? That is an easy one (question), I use the feeler gage, Redding competition shell holders would afford me 5 options from .002" to .010".

The advantage goes to the feeler gage, rational? The feeler gage offers 10 options in thousandths up to .010". BIG +, the feeler gage affords me the additional height above the deck of the shell holder to go to no go-gage height and beyond.

F. Guffey

[243winxb]

M1 http://www.exteriorballistics.com/re...sgunreload.cfm and tool to measure sizing. The fired case may be longer, head to datum, than the chamber. Its been said there is case stretch as the action opens early. http://www.brownells.com/.aspx/lid=1...nd_Maximum_COL

[Bart B.]

The main reason folks sizing cases do not want to use feeler gauges to set and/or use a die when their objectives are best accuracy, ease of tool use, process speed of sizing cases and consistancy of sized case dimensions, is with the right shell holder height. You only have to set it once for several (dozen, hundred or thousand) cases. If you have to stick a feeler gauge between the shell holder and die bottom for every case sized (the only way to get near zero spread in case dimension from head to shoulder) it'll take a lot longer.

And constant compressing a feeler gauge with a small contact area will soon make it thinner. Shell holders have a lot more metal and area to resist squishing to a shorter height. A .002" step across them is fine enough for even the most stringent results. If one demands more, buy two sets then grind .001" off the top of each one in the second set; mark 'em with their new height.

If using a feeler gauge is the only way you understand what's happening and how it works, use it.

That link in post 8: I wish the author had used only one definition of "headspace" instead of at least two. The sentence " My brilliant deduction is that new case handloads and factory cartridges see as much as .011" headspace in my firearms when initially fired, and that is substantial as headspace goes." should be replaced with head clearance so folks won't confuse that with chamber or case headspace.

[F. Guffey]

That link in post 8: I wish the author had used only one definition of "headspace" instead of at least two. The sentence " My brilliant deduction is that new case handloads and factory cartridges see as much as .011" headspace in my firearms when initially fired, and that is substantial as headspace goes." should be replaced with head clearance so folks won't confuse that with chamber or case headspace.
__________________

Bart B., contact the author of the article, tell them how brilliant you are, if they respond with "Fantastic", let me know and I will interpret the meaning, they could have attended the same finishing school I attended.

It is not complicated, the case has a length from the datium/shoulder to the head of the case, the chamber has a length from the datum/shoulder to the bolt face. The case does not have head space, the case has a length (again) from the shoulder/datum to the case head.

I can not find head space on the case according to SAMMI, do I run around hollering "Repeat after me" No,

F. Guffey

[F. Guffey]

If a reloader measures before firing, again after firing and again after sizing the difference in length between the minimum length/full length case and chamber from the case shoulder to the case head and from the chamber shoulder to the bolt face.

If the reloader became a case former they could form first and then fire.

F. Guffey

[Bart B.]

Guffey, I know you cannot find "case headspace" in SAAMI's stuff. There's lots of commonly used terms in the industry and consumer base about ammo, barrels and reloading that's not specifically mentioned in any SAAMI document. What about things that are listed in SAAMI documents? Does that matter at all?

If you look carefully in SAAMI's glossary, that all it's contributing members signed on to use, you'll find "head clearance."

HEAD CLEARANCE
The distance between the head of a fully seated cartridge or shell and the face of the breech bolt when the action is in the closed position. Commonly confused with headspace.

Are you brilliant enough to understand that? If not, stand closer to a turned on light bulb and you'll at least appear to be brighter.

[F. Guffey]

It is not complicated, the case has a length from the datum/shoulder to the head of the case, the chamber has a length from the datum/shoulder to the bolt face. The case does not have head space, the case has a length (again) from the shoulder/datum to the case head.

Then Bart B. got confused:

Guffey, I know you cannot find "case headspace" in SAAMI's stuff. There's lots of commonly used terms in the industry and consumer base about ammo, barrels and reloading that's not specifically mentioned in any SAAMI document. What about things that are listed in SAAMI documents? Does that matter at all?

F. Guffey

[603Country]

I think this calls for a duel. Paintball guns at 20 paces...

I will 'second' Bart. I would second Mr Guffey, but I have no feeler gauges, and therefore feel unworthy.

[243winxb]

calls for a duel.

I have both on my Ignore List. I wont see the blood shed.

[4runnerman]

Good one 603. Guffy-You seem to have a lot of knowledge about shooting and loading.
Do you compete in matches?.

[dmazur]

It is a semi auto also, my trusty M1

Extracting from the first link in post #8,

Full length sizing is the only option in the Service Rifle world. Minimal sizing does have its place in bolt actions, particularly where top accuracy is the goal. It can also be used in some other types of actions when reliability is not a top priority. However, anything other than full length resizing is a potentially serious problem with the Service Rifle. The case needs to be resized to the point that it will enter the chamber freely, completely and with absolutely no hint of resistance whatsoever.

As far as I know, noone recommends minimal sizing for gas guns, which applies to the M1's action type. The consequences make the gain not worth the risk.

Please read the entire link from post #8. This is serious business.

[F. Guffey]

http://reloadingtips.com/how_to/sizi...adjustment.htm

As suggested, I opened the link, first I am told I must understand ext., then it goes straight to cam over. I have Rock Chuckers, none of my Rock Chuckers cam over but to convince me I am instructed to look ‘vary carefully’ at the ram when it moves up. I am informed the ram goes up to the top and then stops and then reverses the direction. A press that reverses direction at the top is a bump press, I have bump presses, all of my Herter presses are bump presses.

A reloader with a video type phone was playing with presses at a cabelas, he lowered the handle on a Rock Checker, when the ram reached the top the ram kicked forward, it was not necessary to ’watch very carefully’ the ram had a very pronounced kick forward at the top. The reloading YouTub-er made a video and then posted. Then the Yah Yah boys chimed in, Chinese made, cheap metal, out-sourcing, and the ‘I aint going to buy anything RCBS anymore’.

The cabelas’ Rock chucker did not have a die in the press, the link instructions above says ‘without a die installed’. With 400 pounds of gigs dedicated to adjusting the die in the press today?? Not easy to make anything fool proof, fools just do not read. reminds me of a poem by John Godfrey Sax.

http://www.constitution.org/col/blind_men.htm

RCBS has printed directions for adjusting dies in presses, the instructions include cam over presses and non cam over presses, the cam over press was referred to as being a bump press, today bump has to do with something that happens when the shoulder of the case runs into the shoulder portion of the die. When I use a bump press I adjust it to bump, when I adjust a non bump press I adjust the die in the press to overcome the cases ability to resist sizing.

I do not find the link a good read. I find no need to ‘look very carefully’ if I thought a press was a cam over press I would measure the amount of cam over in thousandths with a feeler gage or a dial indicator.

F. Guffey

[F. Guffey]

"If you have to stick a feeler gauge between the shell holder and die bottom for every case sized (the only way to get near zero spread in case dimension from head to shoulder) it'll take a lot longer"

Bart B., there are those that think I am doing it top you, there is no way to make something fool proof.

After adjusting the die to, off or below the shell holder secure the die to the press with the lock ring.

Again, you make claims of bumping the shoulder back? .001", I ask "How do you do that? Then you claim you achieve the .001" by trial and error. And then I say if you knew the length of the chamber before you started you could eliminate all the trial and error, but even if you insist on trial and error you could verify the adjustment.

I do not secure the lock ring to the die, I secure the die to the press.

F. Guffey

[Bart B.]

Again, you make claims of bumping the shoulder back? .001", I ask "How do you do that?

It's easy to do. More easy to understand. It's all about headspace.

By setting the full length die's dynamic headspace on the press when stressed by the lubed case in it to .001" less than what I want the sized case headspace to be; typically .002" less than the fired case headspace before sizing it. There's about .001" case headspace spring back from the die's dynamic headspace with the case under maximum compression to what case headspace after the case is pulled out of the die. It ends up .001" less than what it was before full length sizing it. That's how I set a fired case headspace back .001".

Thousands of reloaders do it the same way. There's gauges made to measure the case headspace before and after sizing to about two of four decimal places.

It's easy to set a rimless bottleneck full length die's static headspace with a chamber GO headspace gauge. It's dynamic headspace is usually a few thousandths less. If the rifle's chamber headspace is greater than minimum specs, the die 's dynamic headspace will usually be longer than its static headspace

I think readers have enough space in their head to sort all of this out.

I lock the rings to my dies (both sizing and seating) so they go back into the press with the same headspace I set them for. Not as precise as using feeler gauges each time but good enough for me.

[Bart B.]

Mr. Guffey, aren't you going to comment on the above?

[tobnpr]

Hornady LNL Headspace gauge. Get the set with assorted inserts to cover most common chamberings.

Read the directions. Simple.

As simple as my answer.

Your question seemed simple, too...