How much cam over is enough.??

[codefour]

Well I have been reloading for over a year now. 99 percent handgun.. I thought I would try and reload .308 Win. I bought a set of RCBS dies. I read the instructions. I seated the FL sizer 1/4 turn after contact with the shell holder. I thought it would be enough per the RCBS instructions.

So I lube and size 150 .308 cases. So I took them to friend who has been reloading for 35 years. He pulled out a Dillon Case Gage. Low and behold, they were not sized enough and I had to resize them again.

I use a Redding Big Boss II as my single stage for rifle. How much should I cam over.? I know it is hard to articulate the amount. But, should it be a steady force required to cam over properly. I do not want to bend a die. I know this quesion may seem to be in left-field, but I am kind of confused.

Any help would be appreciated. Thanks in advance.

 

[ants]

The simplest way...

You can use your chamber as a case gauge.
Case gauges are great, but your chamber is the final test.

If the bolt closes cleanly and easily on a sized case, you're good to go.

NOTE: Some single stage presses (like Lee) do not cam over.

The issue is not how far you cam over, but whether or not the case fits the chamber.

 

[ArchAngelCD]

Like you said, it's hard to explain but, here's what I would do... Borrow your friends case gauge, start with that 1/4 turn and turn the die in small increments until the brass fits the gauge perfectly. First make a mark on the die with a marker so you can tell how much you needed to turn the die to get the proper shoulder bump. This way you can adjust the die correctly in the future in case you lose your adjustment for some reason.

 

[noylj]

First, throw out the case gage and make a dummy round (case and bullet, no powder or primer) and see if it functions in your gun.
Next, had these cases been fired in your rifle or from another rifle (if military, from a machine gun)? If so, you may need a special die to size them all the way down.
If you are shooting a semi-auto, you not only need to full-length size, but you may need a small base die.
Do as ArchangelCD says, but be sure you test in your rifle.

 

[ArchAngelCD]

Actually, a "dummy round" is also a good idea after you're sure you have the die correctly adjusted. That's an easier method of readjusting you dies.

 

[Sunray]

"...may need a small base die..." Usually not for a .308.
Set all the dies up so the shell holder just kisses the bottom of the die with the ram all the way up. Never had any issues doing that. As mentioned, the best case guage is the chamber.
You'll never bend a die.

 

[steve4102]

If your 308 is a semi-auto, then by all means use the case gauge. If it is a bolt action through the damn thing away. Use your chamber as a gauge to set up your dies for about .001-.002 shoulder bump.

 

[JimKirk]

Once the shellholder solidly touches the bottom of the die ... there is no more room to cam over(unless the press springs) ...unless you take metal off the top of shellholder or off the bottom of the die. Frank will tell you to put a feeler gauge between the brass and shellholder until you get the chamber feed you need ... but unless you want to do that to every brass ... then the fix is to remove some metal.

Now if your press is springing enough that the shellholder never touches the die ...then you can adjust ...

Jimmy K

 

[ranger335v]

Two points.

First, ignore the case gage, you only need to make YOUR ammo fit YOUR weapon.

Second, there is no magic in "cam over", the ram rises to full height on any press. Cam over simply means the toggle links have driven the ram past top dead center and it has started back down.

We will not break a die with excessive cam force but some people have broken the top strap on iron presses doing that. Such massive ram force is NOT needed to do anything we need done on a press and it's a sign of an amature to damage anything that way. (Well, to keep the howls of protest down, we CAN damage any of Lee's excellant collet neck sizing or FCD rifle crimp dies with excessive force.)

 

[Walkalong]

Bolt action? FL size to fit your chamber. Auto. FL size to fit a case gauge.

http://www.thehighroad.org/showpost.php?p=6270171&postcount=1

Do you need a small base die? Here is a good thread.

http://www.thehighroad.org/showthread.php?t=600269

 

[MEHavey]

So I lube and size 150 .308 cases. So I took them to friend who has been reloading for 35 years. He pulled out a Dillon Case Gage. Low and behold, they were not sized enough and I had to resize them again.

To be blunt, I don't use/trust case gages for my purposes.
And "Camming Over" is not the measure of proper resizing.

Test (Bolt guns): Does a resized/unloaded case chamber? If it does w/o significant resistance, the case IS sized sufficiently, and may in fact be overly sized. (Note, sizing just enough so that the bolt just closes cleanly is both simple, and recommended for long case life.)

Test (Gas guns): Does the resized/unloaded case chamber ahead of a stripped bolt w/o any (repeat, any) resistance? If so, it IS properly sized. (Full length sizing on a gas gun results in shortened case life -- especially on Garand/M-14 actions -- but that is the safest course of action)

In both cases above, once you find the proper die adjustment depth, lock the ring at that point (cam-over or not) and don't fool with it again.

 

[fguffey]

Some times the press wins, other time the case wins and whips the press, AND, the person operating the press is to blame. The operator should be able to determine if the case was sized before the ram is lowered, the reloader acquires bad habits from the Internet, one being the 'first fire to form, then neck size 5+ times THEN start over by full length sizing, and again I ask "How is that possible? The case have been fired 6 times, RCBS says a case stabilizes before it grown .020 thousands when sized in their 'X' sizer die and bench resters claim a case stops growing after 5 firings, unless they are using cases that are exempt from rules I am not aware of.

So to answer your question, I do not have a Redding press, I do have more presses than I will ever ware out, I have a RCBS Rock Chucker, it does not cam over, call it jam, cram or bind over but it does not cam, and for me that is not a problem, I do have Herters, lots of Herters, Herters cam over, when it comes to bump, they bump twice, once on the way up and again on the way down, to keep from making it "more complicated that it needs to be" or "over thinking it", if my RCBS does not win and part of the case is not sized determining the amount 'as in by this much' I use a feeler gage to check the gap between the shell holder and bottom of the die with the ram up, If the press wins there will not be a gap, if a lube is used that was designed very poorly to size case the effort created will put the press in to nine line bind (oil field talk), instead of sizing the case the press will flex.

In the perfect world new cases are used, new cases are predictable, once fired cases are next, the reloader gets into trouble when they believe they can fire a case 6 times and start over.

I determine the length of the chamber first, this tells me the effect the chamber will have on a case when fired, and me being a reloader has the ability to off set the effect the chamber will have on a case when fired, then there MG effect on cases fired as in diameter, bad lube and the inability of 'the reloader' to keep up with a bunch of thought at once, my favorite sizer die is the forming/trim die, when whipping a case into shape it wins ever time and has the ability to move a lot of brass without effort, as in forming a 308 W case from a 30/06 case.

If I am using a bump-bump press as in one that cams over, I use a different technique to determine if the case won or the press won, again, I can not start over with a case that has stabilized, or as reloaders put it, a case that is fully grown, what ever that is.

F. Guffey

 

[fguffey]

and if in my possession there is a die that has the lock ring secured to the die, IT IS NOT MY DIE! I adjust my dies ever time I use them, could be because I have more than one press, an assortment of tool heads, I believe securing the primer punch/sizer ball to the die when not in use is a bad habit, I do use the versatile full length sizer die with the companion tool to the press, the feeler gage every time.

F. Guffey

 

[Walkalong]

"Camming Over" is not the measure of proper resizing.

Absolutely.

 

[fguffey]

Cam over, cram over, jam over or lock up.

"Some times the press wins, other time the case wins and whips the press, AND, the person operating the press is to blame. The operator should be able to determine if the case was sized before the ram is lowered, the reloader..."

Mindlessly going through the motions and following the instructions, full length sizing or restoring a case to minimum length is supposed to be a matter of adjusting the die down an additional 1/4 after making contact with the shell holder.....then if that does not work make an addition wild guesstimate of an additional 1/4 turn and if that does not work..... . The ram travel is limited, when it hits the bottom of the die it stops, additional effort placed on the handle results in strain distortion of the press in the form flex or yield. In the old days (mid 60s, early 70s) 'A' manufacture demonstrated the strength of their presses using deflection/strain gages, the person running the test was not the same person attempting to size a case with a poor case lube, nor the same person that ignores the ability of a case's ability to resist sizing (and one more time, the perfect case is a new unfired case, after that it is down hill), still presses got stronger but reloaders did not get smarter, there/here they are, mindlessly pulling the handle, sizing cases thinking talking about it 'fixes it'? I am beginning to believe reloaders can not handle variables.

I determine the length of the chamber before I start sizing cases, I size a case, measure the case, after sizing the case I determine if my press won or the case won and I know the dimensions between the deck of my shell holder and shoulder of the die, with the die setting on the shell holder the dimensions between the deck of the shell holder and shoulder of the die is = to full length sized/minimum length, UNLESS! the die has been ground by a very misinformed reloader or the shell holder has been ground for the same reason, known only to the person with the grinder without a plan or clue.

I use the versatile full length sizer die, customizing ammo to the chamber is possible with the companion tool to the press, the feeler gage, and when sizing cases for a chamber that is short, I raise the deck height of the shell holder, when sizing cases to off set the effect of head space I lower the deck height of the shell holder, $40.00 seems expensive for 5 shell holders from Redding, use tools more effectively or PAY.

F. Guffey

 

[fguffey]

Cam over, cram over, jam over or lock up.

"Absolutely"

Absolutely what?

F. Guffey

 

[Walkalong]

Come on fguffey, it is pretty obvious, and just what you go on about all the time. Just camming over and calling it good is no way to size.

I try to be clear in my posts, instead of rambling on trying to "make people think" as you say you are.

 

[fguffey]

RCBS dies, Redding press, no ideal what lube, no ideal what brand of cases, I have no ideal what problems/effect tough Lapua cases would present, but he did ask for help and did say he followed directions as to the additional 1/4 turn after contact, and that is the procedure for retuning a case to full length sizing/minimum length. He did a good thing, he got off the Internet and sought help from a friend to determine the difference in case length between his sized cases, again, in the perfect world a new case is sized, then comes once fired, as in provoking reloaders to think, I have no complains, there are times I have 50% success, as in your case I have been successful in provoking you (not my intentions), I have failed to get you to think and again, I ask "How is it possible to start over by resizing a case that has been fired 6 times". And I attempt to apply that logic to Codefours question, he is using RCBS dies, A Redding press?? Nothing suspect there, what kind of lube? How many times have the cases been fired? And I say Codefour could determine if the case was sized before lowering the ram, I suggest he could test the cases ability to resist sizing, I could suggest 20 random cases, size then measure, tools? I make tools, I want for nothing, just the suggestion I do not find it necessary to purchase tools to some provokes them but if you continue to read the forums, home made is a term that is becoming more popular, if that is a problem for some it is not my problem, that is their problem.

I thought this question was about CODEFOUR and you thought it was about us.

F. Guffey

 

[MEHavey]

Code4, . . back to the basic question:

Case gauge aside, if you screw the die down to contact the shellholder with the ram raised to full stroke -- NO cam-over -- does a properly-lubed resized (empty) case chamber in your rifle?


.

 

[918v]

I used to set my die to touch the shell holder, then backed it off a quarter turn to start.

 

[codefour]

Case gauge aside, if you screw the die down to contact the shellholder with the ram raised to full stroke -- NO cam-over -- does a properly-lubed resized (empty) case chamber in your rifle?

Well, in my custom Remington 700 action it does, but feels a tad bit tight to close the bolt. On my M1A Super Match, the bolt will not close and is not locked in battery.

I ordered a Dillon case guage for .308. Should be here tomorrow.

I also use the RCBS lube pad. Maybe I am putting too much lube on the cases. I have stuck a case from not lubing enough before, and i make sure that I lube generously on the roll pad. I also lube the inside of the neck with a brush and said RCBS lube. Could I possibly be using too much lube preventing the die from finishing the FL sizing..?? Yes, I do keep lube off the shoulder of the case.

The cases are once fired Lake City M852 cases. Great brass I have been told. I have had it for years. I had cases of new M852 ammo, so I thought I would start reloading it now that I am down to 400 or so M852 NIB rounds.

Thanks for all the advice. Any further comments are greatly appreciated..

 

[Walkalong]

Could I possibly be using too much lube preventing the die from finishing the FL sizing..??

No. Too much lube can cause dents in the case, but won't keep it from fully sizing. Too much drag on the expander ball in the neck can pull the shoulder forward.

 

[89blazin]

once fired Lake City M852 cases. Great brass I have been told.

That's the right stuff for your M1A. Reload the brass three times max...then toss it.

 

[evan price]

"Throw away your case gauge"... yeah, there's great advice.

In a perfect, ideal world, your brass will have only ever been fired in your rifle. Your rifle will have perfect chamber dimensions in every respect. Your dies will be machined to such fine tolerances that they make perfect cases out of gravel.

Anyway, the correct, bench-rest way to size cases is to set the dies to size so that cases fit your rifle. Usually that means .001" shoulder bump max. Great, if you have only one rifle that uses that size ammo, or are shooting bench rest.

In the real world, I get my brass 1xfired. I full length resize everything first, because I have several choices in rifle. Stuff dedicated to my Rem700 gets its second firing (by me) after a Lee collet die resize. Stuff for the gas guns gets full length sized again. I use a DIllon case guage on every piece of brass. It's in my hand as I work the press, with the neck chamfer tool. Why? Every piece of brass gets checked for length with it, as well as SAAMI chamber size.

SAAMI sets a min and max chamber dimension. Not every rifle is the same size. Resize to SAAMI specs and it will fit any chamber, maybe loose in some. I don't care about brass life- I want function.

Each piece of brass gets lubed, resized, checked for length and headspace before anything else is done.

Ya know? My Rem700 likes brass on the short side. The SAAMI case-guaged brass fits perfectly, bolt just closes on it. I'm lucky I guess.

 

[918v]

I have a better idea: howbout size the brass for each individual firearm? You can keep the die adjustment data in a little log book! It's not that hard.