Need quick help RE: #43 RCBS Shell Holder

[sjt18]

I am having head space problems with my 300 WSM. Maybe just an indication of how much a novice I am but I did not realize that shell holders could make so much difference on head space. The Lee Shell Holder from bottom to the surface that meets the base of the case is about .007" less than the Hornady Shell Holder. I'm guessing that usually doesn't make much difference but with my rifle it does. Even with a light load the bolt lift is stiff with the bullets made with the Hornady and very difficult with the Lee. In short, neither appears to be sizing base to datum correctly with either a Lee or RCBS die.

After the long story, short request. Does anyone have a #43 RCBS shell holder? If so, would you mind measuring it from bottom to top and from bottom to the surface that meets the bottom of the cartridge? If it is more than my Hornady shell holder then I should be able to get head space right for my rifle.

 

[MagnumManiac]

Ok, this is easily fixed with the current shell holders you have.
Screw the decapping stem up until the pin is not protruding, place a feeler gauge of .003" between the case head and shell holder, size it, chamber it, or measure it, and check fit. If this is still tight, go to a NEW piece of brass, use a .004" gauge, check again. When you find the gauge that just lets the case chamber with very slight resistance, go .001"-.002" more.

I can measure a shell holder as you requested, but, if you are not cammed over and there is a gap between the shell holder top and the bottom of the die when you have the ram all the way up, no measurement is going to help you. You are essentially fighting the springiness of the brass and the slop in the press linkages.
Shell holder measured from bottom to top at .250".
Bottom to inside of holder at .125". This measurement is the same if measured from the top of the shell holder down.

Cheers.

 

[sjt18]

Ok, this is easily fixed with the current shell holders you have.
Screw the decapping stem up until the pin is not protruding, place a feeler gauge of .003" between the case head and shell holder, size it, chamber it, or measure it, and check fit. If this is still tight, go to a NEW piece of brass, use a .004" gauge, check again. When you find the gauge that just lets the case chamber with very slight resistance, go .001"-.002" more.

I can measure a shell holder as you requested, but, if you are not cammed over and there is a gap between the shell holder top and the bottom of the die when you have the ram all the way up, no measurement is going to help you. You are essentially fighting the springiness of the brass and the slop in the press linkages.
Shell holder measured from bottom to top at .250".
Bottom to inside of holder at .125". This measurement is the same if measured from the top of the shell holder down.

Cheers.

I bought a RCBS shell holder. It got me to the high end of SAAMI. I had to turn in more than the recommended 1/4 turn and need to do more to make sure I'm not crushing them.

For your solution, I would need to decap separately, correct?

 

[MagnumManiac]

I bought a RCBS shell holder. It got me to the high end of SAAMI. I had to turn in more than the recommended 1/4 turn and need to do more to make sure I'm not crushing them.

For your solution, I would need to decap separately, correct?

Whose recommendation is 1/4 turn in?
You screw the die in until a case chambers without resistance, 1/4 turn in is meaningless.
If you use the feeler gauge, then yes, you need to deprime after you size them.
What are you scared of crushing? Keep turning the die in until a case is sized correctly.

Cheers.

 

[sjt18]

The die manufacturers recommend raising the ram until it touches the bottom of the die then lowering the ram and turning in another 1/4 to 1/3 turn. The instructions for Lee, Hornady, and RCBS have similar recommendations.

I am concerned about crushing the case neck/shoulder. I've done it unfortunately.

 

[Seabeeken]

Ive never crushed a case with cam over. You can adjust the die up and down as needed. Just dont overdo the cam over. You dont want to harm the press.

 

[Hugger-4641]

I've never crushed a 300wsm. You should be able to adjust the die and resolve your issue. If you've adjusted it until the shell holder touches the die with no case, and it is still not sizing the cases enough, then you may need to adjust or shim the shell holder, however what you said was you had heavy bolt lift. If it chambers fine with normal bolt lift, but you have heavy bolt lift after firing, that is not nescessarily a sizing die issue. It could be a case length issue or a carbon ring in the chamber, or It could be overly soft brass is forming into the ejector.
Are there any ejector marks on the case head?
Is there possibly a donut in the brass?
Are your bullets slighly over sized?

 

[JKB57]

put it in a lathe and take about 5 thousands off the top of the shell holder or you can also take that amount off the bottom of the die instead ,have had to to this to a couple rifles over the years rather than trying to turn the die down in the press 1/4 turn or more

 

[sjt18]

Well come to find out my Lee press doesn't cam over at all. It stops at the top of the stroke

 

[sjt18]

Lots to answer. Over tightening my Lee die can definitely crush Winchester brass. I did it with my 7 mm WSM die

The Lee shell holder was a problem. Regardless of which die I used the Lee holder left headspace.014 over SAAMI. The Hornady shell holder from my 7mm wsm set reduced that by about .007". My new RCBS set has me at the top end of spec as best I can tell

No ejector marks or other signs of pressure. I had a good gunsmith check my gun. It is a Savave with a tight chamber and headspace. Still within spec according to his gauges. He polished some machine marks out that may have contributed to the heavy bolt lift.

Brass is Hornady or Norma.

I've never used factory. He fired factory with no problem then some rounds he made with an RCBS die and holder. I now have the same set but haven't finished testing it yet. The test pieces measure right at the shoulder but I need to trim and see if they chamber

 

[Tommy T]

I am having head space problems with my 300 WSM. Maybe just an indication of how much a novice I am but I did not realize that shell holders could make so much difference on head space. The Lee Shell Holder from bottom to the surface that meets the base of the case is about .007" less than the Hornady Shell Holder. I'm guessing that usually doesn't make much difference but with my rifle it does. Even with a light load the bolt lift is stiff with the bullets made with the Hornady and very difficult with the Lee. In short, neither appears to be sizing base to datum correctly with either a Lee or RCBS die.

After the long story, short request. Does anyone have a #43 RCBS shell holder? If so, would you mind measuring it from bottom to top and from bottom to the surface that meets the bottom of the cartridge? If it is more than my Hornady shell holder then I should be able to get head space right for my rifle.

Just buy you a set of competition shell holders they come K sizes my set has 6 in it it goes from 2k to 10K and that will take care of your problem I get mine from OTM in Jacksonville FL . Good luck

 

[Philward]

#43-0.122 and 0.246
#4- 0.1235 and 0.248 from 2 different shell holders

 

[sjt18]

Got a link?

 

[Bitteroot]

I am having head space problems with my 300 WSM. Maybe just an indication of how much a novice I am but I did not realize that shell holders could make so much difference on head space. The Lee Shell Holder from bottom to the surface that meets the base of the case is about .007" less than the Hornady Shell Holder. I'm guessing that usually doesn't make much difference but with my rifle it does. Even with a light load the bolt lift is stiff with the bullets made with the Hornady and very difficult with the Lee. In short, neither appears to be sizing base to datum correctly with either a Lee or RCBS die.

After the long story, short request. Does anyone have a #43 RCBS shell holder? If so, would you mind measuring it from bottom to top and from bottom to the surface that meets the bottom of the cartridge? If it is more than my Hornady shell holder then I should be able to get head space right for my rifle.

A standard shell holder has a .125 deck height.
In a perfect world your die is .125 short of the chamber but chambers can vary a few thousandths.
I can't speak for Lee products or maybe your SH has been shaved..