Titan ReloadingInline FabricationADvertise hereLee Precision
RotoMetals2RepackboxWideners

Results 1 to 17 of 17

Thread: Fire forming necks

  1. #1
    Boolit Buddy
    Join Date
    Feb 2011
    Location
    Queensland Australia
    Posts
    153

    Fire forming necks

    Putting together this 40-72 H Rolling Block.
    The fast twist barrel I was getting made in Brisbane is not going to happen it seems so I have put in a GM 16 twist I had on hand. The reamer came so its chambered now and I sized cases to fit with a die I made with that reamer.
    Now I want to fireform some cases to see if the neck dimensions change.
    My Jim mould came and I cast a bunch of boolits but dont really want to waste them fireforming.
    Will BP and a wad fireform the neck or will it need the pressure buildup from a boolit to blow the necks out?
    These will only be seated in 1/8 or 3/16 or so.
    I was hoping a poly wad right at the mouth would do the trick. I have some cheap Spanish BP on hand so I can use a case full.

  2. #2
    Boolit Master
    Join Date
    Oct 2014
    Location
    california
    Posts
    764
    [I] haven't done case forming with black powder, but have with smokeless. My procedure was to start with a light charge of something like Unique, as it is a fast burning powder. I prime, then powder charge of a little less than I think it would take, top off the case up to just below the mouth with cornmeal,then seal with some melted paraffin to hold the powder and paraffin in place. If the charge isn't strong enough to form the shoulder, then I up the charge a little according to what I see.
    Make sure to clean the paraffin out of the barrel once you are done as there will be some residue.
    It won't be much, and a cleaning rod with a couple of passes with a patch should do nicely.

    I've done quite a few this way and it works very well.

  3. #3
    Just load and shoot full loads, fireforming loads can be surprisingly accurate, it is good practice.

  4. #4
    Boolit Master trails4u's Avatar
    Join Date
    Feb 2013
    Location
    Upstate, SC
    Posts
    858
    Making Werndl brass from .348 Win.....I blow the necks out using 10g or so of Bullseye and (no joke) grass seed for a filler. It's what I had.....so I tried it, and it worked great. Didn't quite blow the body out all the way, but it was 100% effective in expanding the neck diameter.
    "Do not follow where the path might lead, go instead where there is no path and leave a trail" Ralph Waldo Emerson

  5. #5
    Boolit Grand Master Don McDowell's Avatar
    Join Date
    Jan 2008
    Location
    Hell Gap Wy
    Posts
    5,416
    Quote Originally Posted by martinibelgian View Post
    Just load and shoot full loads, fireforming loads can be surprisingly accurate, it is good practice.
    That is the best way to do it without a doubt.
    Long range rules, the rest drool.

  6. #6
    Boolit Buddy
    Join Date
    Feb 2011
    Location
    Queensland Australia
    Posts
    153
    Thanks all. The consensus seems to be shoot it, so I will.
    I have not cut the extractor groove yet so will poke the shells out with a rod.
    Just hoping the necks wont expand too much as they are just right now holding the Jim 395-415E nicely.
    I want to make sure everything is OK before I pull the barrel again to mill the slot. I have no sights on it yet either.

    40-72 H by [url=https://www.flickr.com/photos/141809689@N05/]

  7. #7
    Boolit Master Lead pot's Avatar
    Join Date
    Jan 2006
    Location
    In a State that is #1 with people migrating out.
    Posts
    3,004
    Keith if anything that you might have a problem with is with the die you made with the chamber reamer.
    I been down this path with my reamers. There is too much spring back when you form the cases and they will be a very tight fit in the chamber. When I make up custom chamber reamers I have a second made with reduced dimensions for the sizing reamer to cut the die. Annealing the formed cases can help but they will still be a tight fit. You might make a cartridge seating tool and take a cleaning rod along to the range to extract the fired case. If they are tight it will take a couple firings till they extract the way they should.
    I hope you don't have this problem.
    Kurt

  8. #8
    Boolit Buddy
    Join Date
    Feb 2011
    Location
    Queensland Australia
    Posts
    153
    Right on Kurt. I did have a bit of trouble there so I polished out the chamber a bit till I eventually got them to a stage of a bit of a shove got them in. The ID of the neck is dead on .40. I fired 3 off today and after firing the neck is still .40 so its a tight chamber.
    The reamer print shows 2.510 from the mouth to the front of the rim which appears to be the datum. I trimmed to this but might be a hair over as there seems to be a slight lip.
    It was windy today and the only bit of patch I found was a complete strip that was the base turn over bit. No side bits to be found.
    May be if the case is a whisker long the mouth grabbed it and cut it off. I dont know.
    Anyway, going to pull the barrel now and cut the slot for the sliding extractor. Its in the threads so I hope I dont stuff it up. I have this vintage old mill thats a bit worn , so will have to do my best.
    Jim DT has got a front sight for me when he gets time to make it and I have a tang sight here that I dont know who the maker is. Its a vernier not a Soulle and has small holes drilled in the circumference of the elevation and windage knobs for fine adjustment.
    Any ideas whose it is? I dont know why the makers dont put their name on stuff.
    Keith

  9. #9
    Boolit Master


    rfd's Avatar
    Join Date
    Feb 2013
    Location
    NJ via TX
    Posts
    3,453
    you can also faux fire form by using a BACO straight expander plug in a lyman "M" die (or something similar with regards to the *straight* plug and die body).

  10. #10
    Boolit Master Lead pot's Avatar
    Join Date
    Jan 2006
    Location
    In a State that is #1 with people migrating out.
    Posts
    3,004
    Sounds like your on the way Keith. Seating them in with a cartridge seating tool about three times would have loosed't them up too, but that's a pain in the neck.

    I have cut extractor slots using a file and dremel tool

  11. #11
    Boolit Buddy
    Join Date
    Sep 2006
    Posts
    285
    Keith,
    Your tang sight sounds like a (Kermit) Hoke. Mine has those
    little holes around the circumference of the knobs.
    Should also have elevation scales on both sides of the ladder.
    Very nice for this left hander to have that scale on the right side.
    They are very nice, what with adjustable gibs to
    keep them snug
    beltfed/arnie

  12. #12
    Boolit Buddy
    Join Date
    Sep 2006
    Posts
    285
    Keith,
    Forgot to say that I simply shot full BP loads at matches
    while fireforming my 40-72W rifle brass(Hornady 405W brass). Accurate and not wasted.
    And I did not have to "waste" my time with other kinds of fireforming "tricks"
    beltfed/arnie

  13. #13
    Boolit Buddy
    Join Date
    Feb 2011
    Location
    Queensland Australia
    Posts
    153
    Quote Originally Posted by Lead pot View Post
    Sounds like your on the way Keith. Seating them in with a cartridge seating tool about three times would have loosed't them up too, but that's a pain in the neck.

    I have cut extractor slots using a file and dremel tool
    Yes, I did that yesterday. Took all day. I cut the long slot with the mill then the one that goes across to the case head with a dremel and file then used the mill again to cut the part circle rebate for the rim. That was a bit tricky as my cutter was a lot smaller. Finish it off today.
    Arnie, yes the sight has a scale on both sides. The elevation is tight but the windage has some backlash. Can this be taken out?
    Are they as good as Soule type sights?
    I am fitting the blocks for my DZ scope today too, I hope. Unpacked the scope the other day and found the plunger in the rear mount would not move. Could not budge it . Sent Dan an email. He replied that on one batch the Loktite used migrated along and could lock the plunger. Mine must have been one of that batch. Said to get some acetone , feed in the gap and try and work it with pliers.
    Went to town Friday, bought some acetone, soaked it for a day and after a fair bit of effort got it free. Scratched the plunger up a bit though. I was worried it might not free up but Dan said if it did not then to send the scope back for replacement.

  14. #14
    Boolit Buddy
    Join Date
    Sep 2006
    Posts
    285
    Keith,
    thanks for the question on the windage backlash.

    I have only had my Hoke a couple months. Have used it/shot the rifle it is on only
    twice with the irons. I will check on my Hoke sight re. Windage backlash and get back to you.
    beltfed/arnie

  15. #15
    Boolit Grand Master Don McDowell's Avatar
    Join Date
    Jan 2008
    Location
    Hell Gap Wy
    Posts
    5,416
    Once you get used to them those Hoke sights (and the now defunct Distant Thunder sights) are a bunch handier to use than a soul sight as far as windage adjusments go.
    Long range rules, the rest drool.

  16. #16
    Boolit Buddy
    Join Date
    Feb 2011
    Location
    Queensland Australia
    Posts
    153
    Thanks. I will put it on this rifle then. Save me buying another Soule.
    Distant Thunder is in the process of sending me a front sight to go on it as well

  17. #17
    Boolit Grand Master


    jonp's Avatar
    Join Date
    Feb 2013
    Location
    Planet Reality
    Posts
    6,158
    I have cut extractor slots using a file and dremel tool Dremel?
    I am become death. The destroyer of worlds

    We all do our duty when there is not cost to it, honor comes easier then. Sooner or later there comes a day in every man's life when it is not so easy, a day when he must choose and live with it for the rest of his days.

    The further society drifts from the truth, the more it will hate those that speak it
    George Orwell

    "I prefer dangerous freedom over peaceful slavery."
    - Thomas Jefferson, letter to James Madison, January 30, 1787

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Abbreviations used in Reloading

BP Bronze Point IMR Improved Military Rifle PTD Pointed
BR Bench Rest M Magnum RN Round Nose
BT Boat Tail PL Power-Lokt SP Soft Point
C Compressed Charge PR Primer SPCL Soft Point "Core-Lokt"
HP Hollow Point PSPCL Pointed Soft Point "Core Lokt" C.O.L. Cartridge Overall Length
PSP Pointed Soft Point Spz Spitzer Point SBT Spitzer Boat Tail
LRN Lead Round Nose LWC Lead Wad Cutter LSWC Lead Semi Wad Cutter
GC Gas Check