Results 1 to 15 of 15

Thread: 260 rem. 30 degree improved ? Fireform

  1. #1
    Registered User
    Join Date
    May 2012
    Location
    Portlandia, Or.
    Posts
    373

    260 rem. 30 degree improved ? Fireform

    I have a mauser that I had chambered to this cartridge. Here's the deal. If I don't load it to near max it does not form right and the primer is backed out of the case about .003 to .004. If I load it to near max it forms great. Thoughts? I think it is chambered .002 to long? Can this be a problem? Or do I have a wildcat of a wildcat? Thanks. Dan

  2. #2
    Paid Member stomp442's Avatar
    Join Date
    Nov 2010
    Location
    Safford, Az
    Age
    33
    Posts
    1,065
    sounds to me like you need to seat your bullet to touch the lands so that the case is pressed firmly against the bolt face and the case forms properly.

  3. #3
    Registered User
    Join Date
    Sep 2012
    Location
    Elizabethtown,Pa
    Age
    65
    Posts
    884
    Quote Originally Posted by chukarmandoo View Post
    If I don't load it to near max it does not form right and the primer is backed out of the case about .003 to .004. If I load it to near max it forms great. Thoughts?

    Thanks. Dan
    'ol P.O. warned using a light load tends to allow the case to "bounce" when fired and results in short brass, exactly the condition your having. His instruction, "Use a good stiff load".

    My advice, make sure you have a crush on the neck shoulder junction and use an upper window load for the parent then you shouldn't have any problems.

    Bill
    Each morning eat a live green toad, it will be the worst thing you'll have face all day.

  4. #4
    Registered User
    Join Date
    May 2012
    Location
    Portlandia, Or.
    Posts
    373
    I understand what you guys are saying but what I'm wondering is, can the chamber be cut to long? If so where would the line be drawn as far as being safe? I don't have a comparitor but I know the chamber is longer than the parent case. Just don't know how much? Also I have been only using new brass as parent case. Thanks. Dan

  5. #5
    Registered User
    Join Date
    Sep 2012
    Location
    Elizabethtown,Pa
    Age
    65
    Posts
    884
    Quote Originally Posted by chukarmandoo View Post
    I understand what you guys are saying but what I'm wondering is, can the chamber be cut to long? Thanks. Dan

    Well its certainly possible, but I have a few questions.

    1. Is this a new barrel/chamber or one that was rechambered to the improved?
    2. If you used 260 Rem brass, did you FL size it using a 260 Rem FL die?
    3. When chambering the parent was there a bit of resistance locking the bolt to battery?

    Bill
    Each morning eat a live green toad, it will be the worst thing you'll have face all day.

  6. #6
    Registered User
    Join Date
    May 2012
    Location
    Portlandia, Or.
    Posts
    373
    Quote Originally Posted by BillPa View Post
    Well its certainly possible, but I have a few questions.

    1. Is this a new barrel/chamber or one that was rechambered to the improved?
    2. If you used 260 Rem brass, did you FL size it using a 260 Rem FL die?
    3. When chambering the parent was there a bit of resistance locking the bolt to battery?

    Bill
    1. It was a new short chamber 260 barrel. .050 or close to that.
    2. I used new 7/08 brass and I FL sized w/260 rem. FL dies
    3. No.

  7. #7
    Registered User
    Join Date
    Sep 2012
    Location
    Elizabethtown,Pa
    Age
    65
    Posts
    884
    Well, first of all 7-08 brass is shorter than 260 from the casehead to the neck-shoulder junction, how cartridge head clearance (Not headspace!) is established in a improved chamber.

    Using the drawing above 7-08 brass on the average is .029" shorter than 260 Rem, casehead to the junction. If you want to use the 7 brass then you'll have to create a false shoulder by partially resizing the neck for the required crush, much the same as using 222 Rem Mag brass to make 204 Ruger brass.


    On the flip side you could neck up 243s, the casehead to junction length would then be the same as 260.

    Bill
    Each morning eat a live green toad, it will be the worst thing you'll have face all day.

  8. #8
    Registered User
    Join Date
    May 2012
    Location
    Portlandia, Or.
    Posts
    373
    OK Bill that explains a lot. I never looked that close at the numbers. Thanks. So if I continue to go about it the same way could I run into problems? As you have shown me, that tells me why I get that step in the neck when I size the 7/08 to 260. The reason I use 7/08 is to keep from getting a doughnut in the shoulder neck junction, If that makes sense?

  9. #9
    Registered User
    Join Date
    Sep 2012
    Location
    Elizabethtown,Pa
    Age
    65
    Posts
    884
    When your brass is roughly .029" short, yeah it can cause some problems. It would be akin to shooting a 250 Savage in a 25 Souper (25-308) chamber.

    I don't see a problem using the 7 brass as long as you partially size the necks to form a false shoulder. Just back off you 260 Rem die then start adjusting down it to reduce the neck OD until the bolt will lock down with a slight resistance and use a upper window load for the 260.

    As far as doughnuts, I wouldn't be overly concerned at this point. If they do form it also depends a lot on the amount of freebore your chamber has and the bullets your using if they'll be a problem. If you are able to seat bullets out past the shoulder-neck junction doughnuts won't be an issue.

    Bill
    Each morning eat a live green toad, it will be the worst thing you'll have face all day.

  10. #10
    Registered User
    Join Date
    May 2012
    Location
    Portlandia, Or.
    Posts
    373
    Thanks Bill !

  11. #11
    Registered User
    Join Date
    Sep 2012
    Location
    Elizabethtown,Pa
    Age
    65
    Posts
    884
    Quote Originally Posted by chukarmandoo View Post
    Thanks Bill !
    No problem.

    Oh BTW, DO NOT resize the parent cartridge in your improved FL die otherwise you'll push the junction back to the post Improved location. Remember, the improved casehead to junction length will be .004-.006" shorter than the parents's. The most you want to do is fix up the necks if needed , fire them As-Is.

    Bill
    Each morning eat a live green toad, it will be the worst thing you'll have face all day.

  12. #12
    Registered User
    Join Date
    May 2012
    Location
    Portlandia, Or.
    Posts
    373
    Quote Originally Posted by BillPa View Post
    No problem.

    Oh BTW, DO NOT resize the parent cartridge in your improved FL die otherwise you'll push the junction back to the post Improved location. Remember, the improved casehead to junction length will be .004-.006" shorter than the parents's. The most you want to do is fix up the necks if needed , fire them As-Is.

    Bill
    I don't. Thanks for the heads up.
    One more ? I haven't done this but was wondering, is it a no-no to fire form used brass?
    The reason I'm asking is, say I have standard 260 reloads and I'm out of the improved loads.
    Last edited by chukarmandoo; 05-28-2013 at 01:57 PM. Reason: more detail

  13. #13
    Registered User
    Join Date
    Sep 2012
    Location
    Elizabethtown,Pa
    Age
    65
    Posts
    884
    Quote Originally Posted by chukarmandoo View Post
    One more ? I haven't done this but was wondering, is it a no-no to fire form used brass?
    The reason I'm asking is, say I have standard 260 reloads and I'm out of the improved loads.
    I generally recommend using new virgin non FL sized brass when asked that question. If your brass has only one firing/loading cycle on it you should be OK. Where it causes problems is when the brass is work hardened from loadng/firing cycles.

    Bill
    Each morning eat a live green toad, it will be the worst thing you'll have face all day.

  14. #14
    Bill, You did an awesme job pointing this gentleman and many others in the right direction. Good form!
    Last edited by stangfish; 05-29-2013 at 06:38 AM.

  15. #15
    Registered User
    Join Date
    May 2012
    Location
    Portlandia, Or.
    Posts
    373
    Thanks Bill. You have passed along a lot of information. Like stangfish stated. Funny thing is, this went a whole different direction than I first thought. Thanks again. Dan

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •