Head space problem?

[rickyrebar]

Hello, I was directed to this forum by some guys @ longrangehunting.com, they said you guys would be able to help me out.
I am new to reloading, I have just completed reloading a dozen .300 WSM, from once fired winchester nickel plated brass. My rifle is an over the counter Model 70 Winchester.
I used a method recommended in The Nosler reloading manual #6, to determine "my" rifles bullet seating depth... using a fire formed case and bullet of choice, I colored the bullet with permanent ink, flatten the case neck to hold the bullet, insert bullet into chamber, close bolt (don't fire), open bolt and retrieve case & bullet re-aligning the bullet back into the case to match the line left by the flattened edge of case neck... doing this 3 times and get an average length, subtract .015" this is "my" riles seating depth. (which for my rifle is 2.930).
I full length resized my cases with an RCBS die, setting it up per their instructions (raising the ram to top of stroke, installing die until it contact shell holder installed on ram, then lowering the ram, thread die 1/4 turn down, raise ram back up to contact die and it should cam over).
Once the cases were re-sized, I measured OAL and trimmed all them down to 2.080" (recommended trim length per RCBS case trimmer instructions), 2.10" is the spec. length.
OK, so here I am with resized cases, trimmed, seating die set to "rifle seating depth", I made up 12 cartridges.
My problem is that when the new cartridges are chambered, the bolt closes hard. I experience this with factory ammo... say 1-2 bullets out of a box of 20, never thought twice about it, but now with "custom fit" ammo?
At first I suspected that the overall cartridge length was too long, so I made a dummy round with a re-sized case with the bullet seated to factory specs. (2.860"), same thing happened, bolt closes hard. I then considered that the diameter of the case was the issue, factory dimension is .555", actual dimension of resized case .500".
As stated above, I am new to all of this and trying to figure out what is the problem, or is a "hard to close" bolt common in a "custom fit" round?
Any help would be appreciated.
On a side note, I have read on another forum somewhere of a similar problem and people were suggesting that the shell holder needed to be ground down, or the bottom of the re-sizing die ground down, or send the sizing die back to RCBS with 5 fire formed cases, they will determine if it is a flaw in the die or an abnormality in the rifle.
Thanks...

 

[BoydAllen]

First of all, I would recommend that you invest in a way to accurately measure from some diameter on the shoulder to the case head. Hornady and Sinclair make tools to do this, that are attachments for dial or digital calipers. Once you have equipped yourself with one of these tools, I suggest that you measure your loaded rounds "headspace". (This is not really the correct use of the term, but I use it in quotes for lack of a better one that is commonly understood.) What you will probably find is that because the WSM brass is so thick at the shoulder, and cases' annealing is non uniform, is that the amount that the shoulders have been bumped back varies considerably, and the long ones are the tight ones. Rough and dirty, you can play with the die adjustment for each of the cases that are too long from head to shoulder until you hit the desired amount of shoulder bump. This is time consuming, but it will work. Beyond that you are into the realm of annealing, which I do not recommend for a beginner. There is so much bad information offered on the internet on the subject that you need to be careful about who you listen to. Another thing, the way that die manufacturers tell you to set dies is wrong, as are those that tell you to do it by feel. Buy the tool. Also, just because the die touches the shell holder doesn't mean that you can't adjust the die any further down, if you have a press that does not toggle over, like my Rockchucker, you can set your die to touch, insert a lubed, fired case into the shell holder, raise the ram to the top of its stroke, whereupon you will see a gap that wasn't there before. You have this amount of additional room to adjust the die downward. Understand, there are good reasons for not bumping shoulders back too much. Over time and repeated loadings cases whose shoulders have been bumped excessively can have head separations...not a good thing. Ultimately, what my friend did to solve the same problem was to by an annealing machine and follow Ken Light's method for how hot to get the brass. His shoulder bump for the PROPERLY annealed cases, is +- .0005. This is an expensive way to go, but it worked well. Just understand that improperly done annealing could cause very serious injury, if a case head is softened and fails.

 

[rickyrebar]

So... you are saying that the die may need to be adjusted down further onto the ram? If I did this a little at a time until I found an adjustment where the resized case would chamber without any resistance felt in the bolt?

 

[watercam]

Before you go any further, go to a gunsmith and have them check your rifles headspace. If your chamber is shorter than spec (mass produced factory chamber - it could happen). You can do it yourself with GO, NO-GO gauges that you can rent from
4-D Products (about $8/week). Bolt should close on a GO gauge but not on a NO-GO gauge. I had the very same problem with a Ruger and the chamber was tight. Since I could close the bolt I left it as a tight fit can contribute to good accuracy.
Your trim length should be .010" shorter than the spec case length.

 

[BoydAllen]

No, I am saying that feel is not reliable and that you should spend a small amount of money and buy an attachment for your caliper so that you can measure shoulder bump.

 

[Mikem]

I have some concerns when you said you even had hard bolt closing on some Factory ammo, this tells me the headspace may not be set quite right from the factory. And should be checked by a good gun smith, or the factory. If you understand the problem, you could even check this yourself with a set of GO-NO GO gauges.
If the headspace is set wrong, (To short) every thing you do to try to compensate for it, is treating the symptom, and not the cause. This is where I would look for the problem first.