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schnyd112
05-28-2016, 11:59 AM
My sizing die does not move the shoulder on fired brass. I can see on the neck that there is part of neck that does not get sized, therefore, the shoulder does not get bumped at all. This is with the die cammed over on the shell holder. It does not seem to affect accuracy, but after 3 firings the brass has hardened enough that it takes some pressure to chamber the round.

I use a Forster competition full length sizing die with rcbs shell holders in an rcbs press.

I know after 3 firings I need to anneal, but I want to make sure I am bumping the shoulder before I start that. Any suggestions/methods for either removing material from the bottom of the die or, the top of the shell holder?

Robinhood
05-28-2016, 12:18 PM
1) Have you checked head space on your rifle?( it could be set too short.)
2) Do you have a way to measure the base to shoulder length of your fired then after sized brass to make a comparison? (in some instances the shoulder to base dimension actually grows right before the shoulder gets bumped depending on the differences of your die and chamber)
3) You are right about anealing. Spring back not only gaurantees inconsistency in sizing it also creates variables in neck tension. IMHO a die that is honed or reamed for minimum sizing on the neck is optimal while coninuing to use the expander ball is ideal most of the time.
4) The information in the previous three points may provide an oportunity to make the proper adjustments in your process or rifle.
5) If all is well with the above, then a conversation with Forster would be a good idea.

What press are you using?

schnyd112
05-28-2016, 12:30 PM
1. Headspacing is done correctly as far as I can tell. I am shooting a Remington 700 in .260 so I can't really change the headspace without getting in pretty deep.
2. Yes, I check every round. There is very little variation from virgin, once fired, twice fired and full length sized. Using my rcbs die I can bump the shoulder, but it really works the neck. As in sizes it down to .285 w/o the expander ball.
3. Don't want to anneal before I get this solved. I had thought about sending the die to get honed, but really don't need to. Fired brass comes out .293-.294 neck. Without the expander ball the neck gets sized to .289. With the ball they come out at .292. Loaded rounds are .293.

I believe it is the combination of a Forster die with rcbs shell holders.

m12lrs
05-28-2016, 02:17 PM
Just so I am understanding you correctly

So you have used this

http://ads.midwayusa.com/product/479704/hornady-lock-n-load-headspace-gage-5-bushing-set-with-comparator?cm_vc=ProductFinding&cm_mmc=ps_google-_-google-_-GS_Tools_Jigs_Fixtures_Beta_G-_-hornady+headspace+gauge&gclid=CjwKEAjwg6W6BRDn6v__7vzN9QkSJAC9l9C3-m6iDnHUOhoLZ0Q2uBEF8eXs5wTuBFY0qoGHsDJWLhoCc7Pw_wc B

And with the die turned all the way down to the shell holder and caming the press over there is no difference between fired brass and resized brass?

But with your rcbs die there is.

Sounds like a bad die to me. I have a bunch of forster dies. That would suprise me. Maybe they accidentally sent you a neck sizing die.

schnyd112
05-28-2016, 02:25 PM
That is correct. It was recommended to me to take material off of the top of the shell holder or the bottom of the die. Problem there is I do not have a grinder or a lathe.

Robinhood
05-28-2016, 04:06 PM
Do you have any sandpaper and a very smooth surface? You can lap the die down a few thousands with no problems.

LongRange
05-28-2016, 07:04 PM
check your phone B.

bigedp51
05-28-2016, 07:48 PM
schnyd112

My Forster full length 30-06 die is labeled (Forster 30-06 FLS -S) I use a Rockchucker press and a RCBS shell holders and Redding Competition Shell Holders.

As stated earlier by m12lrs I also think you have a neck sizing die, and if so your die will not be marked as my die is.

This does not mean your shell holder might be at fault so you should measure your shell holder and also check the diameter of the case before and after sizing.

When I need to lap a shell holder I use a thick piece of glass cut to the size of a sheet of wet and dry sandpaper. I wet the glass to hold the sand paper in place and lap the shell holder in a figure eight pattern with oil. Rotate the shell holder frequently in your hand and also check to make sure the top is even and level.

Fat Albert
06-17-2016, 01:51 PM
Your headspace could be OK but you might have a fat chamber. If the body part of the chamber is too large in dia. (on the high end of SAMMI spec. or over) and your full length die is min. could be your problem. When you size the case, the body of the case is pushed in and the shoulder is pushed forward. Do unsized fired cases chamber in the gun? How much larger is the rear of the chamber than the web of a new factory case? How much dose the case oal length and body dia. change when a case is sized? If your sizer is too small for your chamber than you are over working the cases to get them to fit.

yobuck
06-17-2016, 02:07 PM
The problem could well be the shellholder. The easiest thing would be to get a set of competition shell holders from Sinclair.
Follow the directions, but it amounts to changing the shell holder until you get to the one allowing the bolt to close on the resized case.
This might also be a problem Local 41 is having with his new barrel and brass not chambering.

LongRange
06-17-2016, 04:23 PM
Your headspace could be OK but you might have a fat chamber. If the body part of the chamber is too large in dia. (on the high end of SAMMI spec. or over) and your full length die is min. could be your problem. When you size the case, the body of the case is pushed in and the shoulder is pushed forward. Do unsized fired cases chamber in the gun? How much larger is the rear of the chamber than the web of a new factory case? How much dose the case oal length and body dia. change when a case is sized? If your sizer is too small for your chamber than you are over working the cases to get them to fit.

his barrel was chambered with my reamer which is actually 0.0005 under sammi spec at the 200 mark so its not a fat chamber its his sizing die length or the shell holder and im leaning toward the shell hold because i shot out 2 barrels chambered with the same reamer using the same die but different press and shell holder...ive also had a few dies that were long and had the smith shave a little off the bottom and that took care of the issue.

Robinhood
06-17-2016, 05:35 PM
his barrel was chambered with my reamer which is actually 0.0005 under sammi spec at the 200 mark so its not a fat chamber its his sizing die length or the shell holder and im leaning toward the shell hold because i shot out 2 barrels chambered with the same reamer using the same die but different press and shell holder...ive also had a few dies that were long and had the smith shave a little off the bottom and that took care of the issue.

You and I know this means nothing if the centerline of the reamer was not in the same axis with the barrel. Hopefully it is the shell holder or the headspace.

LongRange
06-17-2016, 09:09 PM
Agree but my head space gauge was used as well...the smith we use is good so I doubt it's a head space issue

schnyd112
06-17-2016, 09:51 PM
Fired, unsized case does chamber. There is very little, if any, measurable change in body dimensions when full length sizing. I can see the die contacts the case, but it is less than .001" difference between a fired and a sized case body. The only real difference I see is neck dimensions. Fired case-.293. Sized, no expander- .288. Fired, sized, expanded-.292. Loaded is .293. I do not have the reamer print in front of me, but like longrange said the reamer cuts tight just in front of the web.

This is an issue with the shell holder shoulder being too tall, not allowing the die to size all the way to the shoulder or the die itself being too long. Even when cammed over I get no change on the shoulder. I can see, on the brass, that there is a portion of the neck that does not get sized.

I am in the process of annealing everything after 3 firings. The problem is minuscule, after 2 firings the bolt does not close as easily. Accuracy seems unaffected 170 rounds after recognizing the problem. Round count on the barrel is 630.

BillPa
06-18-2016, 01:08 AM
This is an issue with the shell holder shoulder being too tall, not allowing the die to size all the way to the shoulder or the die itself being too long. Even when cammed over I get no change on the shoulder.

Try slipping a .002"-.003" shim between the cashead and the floor of the shellholder then size a stick. The shim will raise the case up into the die further even if the die is touching the top of the shellholder. If you then bump the shoulders you have a few options.

The easiest and 'less expensive' option than the Redding holders, use a .115-120" shellholder and die shims. Initially set the die up for the amount of bump with the .006" shim under the die lock ring then later if you need more or less simply use a thicker or thicker shim instead of having to readjust the die.
http://www.sinclairintl.com/reloading-equipment/reloading-dies/replacement-parts-amp-upgrades/skip-s-die-shim-kit-7-8-14--prod33197.aspx

Bill