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Head Space Problem in Ruger #1 WSM

Discussion in 'Handloading and Reloading' started by lbarney, Sep 8, 2010.

  1. lbarney

    lbarney New Member

    I have a problem with head space in my Ruger #1 300 WSM. Let me explain.

    I start with factory brass. I use Reloader 17 powder. The barrel is a Shilen Match Grade, 26" long, light magnum contour. When the once fired cases were measured I discovered that the cases were stretching consistently 0.009" in head space length. This concerns me. When I full length re-size the cases, the next time that I fired them, the cases exhibited the beginnings of head separation. I reset my die to re-size the cases to bump the shoulder 0.002". When this is done, the cases will not seat in the chamber. When I only neck size the cases, they still will not chamber. I am at a loss as to what to do. Any advice out there?:confused::confused:
  2. Captcurt

    Captcurt Well-Known Member

    Run a couple of factory loads thru it. Measure them before and after you fire them. If you still have that much stretch, it is time to see your local gunsmith.
  3. MEHavey

    MEHavey Well-Known Member

    Before you do any resizing (i.e., using a case just fired) will the case chamber then?
  4. Slamfire

    Slamfire Well-Known Member

    I don't know if your rifle headspace is correct.

    Do you trim your cases?

    I do not understand why cases sized .002" below chamber won't seat unless it is a die issue. Or oversized case head from a sloppy chamber job.

    I don't know how you measured your cartridge headspace. A Wilson type gage is dimensionally correct, those Sinclair Comparators are just relative gages.

    Something is really out of dimension.
  5. fguffey

    fguffey Well-Known Member


    I have an old propeller that was removed from a J1 Standard Standard trainer, by those that flew the plane claim the parts were not connected, they described the plane as a group of parts flying loosely together, some rifles are like that, the Lee Enfield 303, the 30/40 Krag and some of those brake over guns, to me it sounds (looks) like the Ruger #1 could be added to that category of guns that jump, stretch, flex and then snaps back together to give the appearance nothing happened.

    Head space checking for the most part is checked statically, no pull, no push and with no effort in the form of pressure. You said the case indicated it stretched .009 thousands, If a case is going to stretch .009 when fired I know it before it is fired, I check head space first to determine the effect the chamber is going to have on the case when fired,,,as opposed to firing first to determine the effect the chamber HAD on the case when fired.

    I do not bump, sounds too much like an accident, as to adjusting the die to reduce the length of the case from the head of the case to it's shoulder .002 thousands when the case indicates an increase of .009 when fired, most cases fired in perfect chambers will indicate an increase of .005 thousands, the difference between a full length sized case and a go-gage length chamber. If you can adjust the die for a .002 set-back you set the shoulder back .005 thousands, point being if the case would not chamber when you sized the case with .002 thousands set-back you could have continued increasing the amount of sizing until the case chambered.

    As to case length, I have no problem cutting half the neck off or necking it down to get it out of the way.

    F. Guffey
  6. Strongbad

    Strongbad Well-Known Member

    "the beginnings of case head separation" means what? I'm not trying to patronize, just trying to get the specifics. Are the cases splitting or have you checked the inside of them with a feeler of some sort?

    Who did the gunsmith work? Did you have Shilen do it in house, or did you have a local gunsmith do it? If it's a local gunsmith, I'd be having this conversation in tandem with him/her as well.

    As someone else mentioned, I'm also curious how you measured your cases. Anyway, keep it coming. One way or another we'll get it sorted out.
  7. steve4102

    steve4102 Well-Known Member

    This is good advice.
  8. lbarney

    lbarney New Member

    Thanks to all of you for your replys. To answer a few questions, I use a Stoney Point Headspace tool to measure the head space distance on the new unfired and once fired cases. I am not lucky enough to have a go no go guage in my tools. I had a local gunsmith do th work for me.

    I have to admit that this is new ground for me. I have not in the past had this problem with any of the rifles that I have had. I am starting to feel like a newbe all over again.

    As to the indication of head separation, some of the fired cases have started to crack and the visable line around the case in front of the case head can be felt as well as seen. I also have started using a paper clip with a small bend on one end and sharpened to a point to feel the inside of the case in the area of the just ahead of the head. Those that I feel have a distinct line that catches the point of the clip, I sort out and throw away.

    The average headspace length of 10 fired cases in this particular rifle is 1.7405". The measured unfired factory cases show the following lengths. Winchester - 1.731", Remington - 1.726". I also have to confess that I have not fired any factory ammo in this rifle. I do know that the new unfired cases chamber easily ( slide right in). The over all length guage from stoney point give a length to where the lands and the ogive of the bullet meet as 2.468".

    Is it always necessary to have the press ram cam over as it contacts the bottom of the sizing die to properly size the cases? When the die is backed off to allow the 0.002" bump in the shoulder the ram does not cam over.

    Again, I really appreciate you help. Some day, this problem too will be remediated.
  9. rcmodel

    rcmodel Member in memoriam

    No, not as long as you use a complete handle stroke every time.

    The press is camming over, but you just can't feel it because you are not trying to compress a steel sizing die, just the soft brass case.

    I fully support what has already been said.

    Except the part about using the Stony Point tool.

    All you need to use is the #1 rifle itself.
    Size just enough that the action will close with slight resistance on a sized case, and no more.
    Thats as near perfect headspace as you can get.

    And closer then you can get with any case guage ever made.

  10. Captcurt

    Captcurt Well-Known Member

    True, so true!
  11. MEHavey

    MEHavey Well-Known Member

    I never like for something to happen (even good things) that I do not understand.
    (Because bad things can then happen that I can't predict.]

    Observation#1: As stated above, "camming over" is not necessary to properly resize if you are sizing/measuring for custom fit.
    Observation#2: Given your paper clip data, the rifle's chamber dimension is not matched to the case dimensions. Eventual case separation is assured.

    Question#1: Given your (average) fired case measures out at 1.7405" (w/the Stoney/Hornady Comparator), will that case then fit back in the rifle before resizing?

    Question#2: Are you then telling us that cases resized (as "measured") to 1.7385" (bumped 0.002") will then not chamber?

    Note that the RCBS precision mic table shows minimum headspace dimension to be 1.7260", and MAX dimension to be 1.7360". If your fired case (unsized and measuring 1.7405") fits back in without interference, you have evidence of the the rifle is the problem.
    Last edited: Sep 9, 2010
  12. Silent Sam

    Silent Sam Well-Known Member

    I don't believe Ruger ever chambered any #1s in 300WSM. I would be highly suspect of that chamber. Playing with die adjustment won't fix an out of spec chamber. Get it checked and proceed from there.
  13. ranger335v

    ranger335v Well-Known Member

    The actual headspace of a bottle neck chamber is typically 7-9 thou, min to max, but that's basically irrelivant to a knowledgable handloader. Just size your cases so they actually fit the chamber and all will be well.

    Cam-over, no cam-over as, such, makes absolutely no difference. All that matters is how far you're jamming the cases into your FL sizer. Your Stoney Point gage is telling you that you're going in about 8-9 thou too far. Two firings with that much stretch IS pretty close to a head seperation.

    Back your sizer die off/up about 1/8th turn (very near 9 thou) from where you have it and try sizing again, your fit should be real close. Keep sizeing, measuring and comparing to fired shoulder location until you get sized shoulder set-back no more than 1-2 thou. After all, it has already shrunk back a thou or two from the full chamber dimensions.
  14. NCsmitty

    NCsmitty Well-Known Member

    I believe that might be right, as they would want to see the 300 RCM in their rifle.

    The whole deal smells like a custom with a Shilen barrel installed, the question being was the 300 WSM chambered properly?

    The OP has not given any history on this rifle, so it's anyone's guess.
    It should be handed back to the gunsmith who did the job, he might already know about the problem.

  15. snuffy

    snuffy Well-Known Member

    Re-read the OP's 8th post, he says;

    It's harder to get the headspace right on a single shot. You can't simply turn the barrel in further, you have to be right the first time. I don't know how a #1's barrel is mounted to the action, so i might be wrong. Possibly the BBL. could be mved back after trimming a few thou. off the rear?

    It won't fix the chamber being too long, but it will compensate for it's over length, to allow shells to be loaded that won't separate.

    My Browning A-bolt in 300 WSM just happens to run well with loads sized with the shell holder tight against the die. I love it when a plan comes together!:D
  16. Greg Mercurio

    Greg Mercurio Well-Known Member

    About 20 years ago I had a Ruger #1 30-06 rechambered to .30-.338 for an Alaska hunt. Fire forming the brass from .338 Win the WRONG way gave symptoms similar to the above. The chamber meets requirements , but is on the long side of the tolerance range. I suspect the gunsmith had a little runout in his spindle and a little play in the gibs. :(

    Using the same techiniques used for fire forming Herrett and TCU cartridges for my Contender eliminated case stretch and greatly improved case life.

    You might try necking UP the cartridge to perhaps .338 then necking back down to give a false shoulder. Move the shoulder back in steps until the faling block cams the cartridge into the chamber. Fire form using whatever method you prefer. I like Trailboss as it is easy on the shoulder when forming large quantities of brass. Out of the chamber pops the most beautiful cases you've ever seen. Once this is done, neck size only.

    And even with the chamber on the large side, the rifle shoots under MOA all day long. In moose country this is more than ok with me. :D
  17. ReloaderEd

    ReloaderEd Well-Known Member

    Ruger #1 wsm head space problem

  18. Silent Sam

    Silent Sam Well-Known Member

    If I paid someone to rechamber/rebarrel a rifle and it exhibited the results he is describing I would expect it to be made right, not try or have to compensate for it. Just my opinion, you all can deal with it as you see fit.
  19. Greg Mercurio

    Greg Mercurio Well-Known Member

    With all the variables involved from the chamber to the brass, it's a bit disappointing to see everyone blaming the gunsmith. Without a chamber cast he's innocent until proven guilty. Cerrosafe is cheap, like advice.
  20. 918v

    918v Well-Known Member

    Do this:

    Size the case in the FL die with the expander assembly removed. Bump the shoulder .002". Chamber the empty case. If it fits, then you know the expander assembly is pulling the shoulder forward and increasing the headspace on the way out of the die. If that is the case. lube the inside of the neck. I use a Redding body die and a Lee Collet Neck Die. I don't have these problems. Also you may want to invest in a Redding competition shellholder set. You get 5 shellholders that are designed to adjust headspace in .002" increments. It is simple: just screw the sizing die to cam over the shellholder and forgetaboutit.

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