Page 3 of 3 FirstFirst 123
Results 31 to 44 of 44

Thread: New to 30 BR - Robinnett case specs

  1. #31
    Join Date
    Jan 2016
    Location
    Iowa
    Posts
    97
    Danyboy

    With all the variations in chamber reamers!

    I will make myself a case length plug if want to know the actual length the reamer cut or if someone altered the original chamber that was cut!

    I will trim a piece of brass short then full length size case and insert the plug. Seat the plug long then put in rifle and close the bolt it will push the plug into case. Open bolt remove case and measure overall length. I trim my brass .010 short of that measurement.

    My 30BR .330 neck plug is brass with a .330 dia cut square on one end and .3085 bullet dia on the other end. If you know someone with a lathe they can make you one.

    Not all chamber reamer drawings match the actual chamber reamer dimensions.

    Have fun with your 30BR!
    Russ
    Click image for larger version. 

Name:	IMG_20200607_110932288_HDR.jpg 
Views:	277 
Size:	68.5 KB 
ID:	23659Click image for larger version. 

Name:	IMG_20200607_111041721_HDR.jpg 
Views:	251 
Size:	66.6 KB 
ID:	23658

  2. #32
    Join Date
    Jun 2010
    Location
    USA
    Posts
    702

    Thumbs up THank you, Russ.

    Quote Originally Posted by R Stiner View Post
    Danyboy

    With all the variations in chamber reamers!

    I will make myself a case length plug if want to know the actual length the reamer cut or if someone altered the original chamber that was cut!

    I will trim a piece of brass short then full length size case and insert the plug. Seat the plug long then put in rifle and close the bolt it will push the plug into case. Open bolt remove case and measure overall length. I trim my brass .010 short of that measurement.

    My 30BR .330 neck plug is brass with a .330 dia cut square on one end and .3085 bullet dia on the other end. If you know someone with a lathe they can make you one.

    Not all chamber reamer drawings match the actual chamber reamer dimensions.

    Have fun with your 30BR!
    Russ
    Click image for larger version. 

Name:	IMG_20200607_110932288_HDR.jpg 
Views:	277 
Size:	68.5 KB 
ID:	23659Click image for larger version. 

Name:	IMG_20200607_111041721_HDR.jpg 
Views:	251 
Size:	66.6 KB 
ID:	23658
    That's what everyone should do.RG

  3. #33
    Join Date
    Feb 2003
    Location
    Lower Dakota Territory
    Posts
    2,183
    Quote Originally Posted by R.G. Robinett View Post
    That's what everyone should do.RG
    Amen! I have a bunch of case length plugs made from 12L14. -Al

  4. #34
    Join Date
    Feb 2003
    Location
    Houston, Texas
    Posts
    8,053
    I make one of these for each chamber. It lets me see what’s really going on in there.

    http://benchrest.com/attachment.php?...1&d=1591631014

    It looks cool on the loading bench too
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	B4AA8E7A-70CD-4DBE-9E8F-1A98DAD38168.jpg 
Views:	549 
Size:	2.06 MB 
ID:	23660  

  5. #35
    Join Date
    Dec 2003
    Location
    washington.........STATE that is.
    Posts
    11,228
    Or, for 50 bucks, get a Teslong and go LOOK in there




    https://www.youtube.com/watch?v=J6tbYYEjsqA

  6. #36
    Join Date
    Jun 2010
    Location
    USA
    Posts
    702

    Thumbs up

    Quote Originally Posted by jackie schmidt View Post
    I make one of these for each chamber. It lets me see what’s really going on in there. It looks cool on the loading bench too
    Got those gizmos too, but have hard time keeping the gremlins from playing with them. What amazes me is how few smiths seem to either offer, or, talk the their customers into obtaining these gizmos. RG

  7. #37
    Join Date
    Mar 2009
    Posts
    323
    Those are a great idea. Ill have to see i can get someone to make me a couple.

    Thanks

  8. #38
    Join Date
    Mar 2009
    Posts
    323
    On a similar question is there a way to measure the actual neck diameter?

    Thanks

  9. #39
    Join Date
    Jan 2016
    Location
    Iowa
    Posts
    97
    TrxR

    For a 30BR .330 neck!

    I use .338cal reamer bushing's on a grizzly rod to check chamber neck DIA.

    For the unkown chamber I use cerrosafe.
    Last edited by R Stiner; 06-10-2020 at 08:54 PM.

  10. #40
    Join Date
    May 2008
    Location
    Group W Bench
    Posts
    132
    Quote Originally Posted by TrxR View Post
    On a similar question is there a way to measure the actual neck diameter?

    Thanks
    I think this might work.

    https://www.amazon.com/Starrett-S830...+hole+gage+set

  11. #41
    Join Date
    May 2010
    Location
    Drummondville, QC, Canada
    Posts
    50
    Quote Originally Posted by R.G. Robinett View Post
    Greg, THE problem: which reamer print?!!? If the smith cannot/will not say, one needs a new smith!
    Sadly, some appear to have not a clue . . . to quote Bob Dylan - again - "the times they are a changin' . . . "RG
    In this part of Canada, gunsmiths are very rare. I ordered a prefit Shillen barrel from Mystic Precision and got an answer this week saying there shouldn't be anythin wrong with my chamber, to compare my fired cases with other shooter's cases, that they have been selling them for 20 years without any issue.
    Do you think If I shipped you a fired case you could tell there if there is a problem ? To me, not being able to fill the case with more than 29.5 grains of IMR4198 when other fellow shooters can fill around 34.7 grains of the same powder is not normal. We're talking a 5 grain difference and this handicaps me quite a bit here.

  12. #42
    Join Date
    Nov 2016
    Location
    Kersey CO
    Posts
    26
    You need to use H4198 instead of IMR4198 . IMR4198 is a long stick powder where H4198 is a short kernel. Most everyone uses H4198 or LT30 with 110 to 118 grain Bullets

  13. #43
    Join Date
    May 2010
    Location
    Drummondville, QC, Canada
    Posts
    50
    Everything's fine with my 30BR now. I ended up measuring my chamber length using this method:

    http://bulletin.accurateshooter.com/...-length-gauge/

    Dave Kiff (who does the chamber reaming for Pacific Tools) sent me 3 possible reamer prints my chamber might match. My chamber is 1.525" long like one of the drawings says.
    Using cerrosafe, my chamber neck OD is .330". Expanded 6BR cases with K & M .243 to .270 AND .270 to .308. Trimmed necks to .010" thick, necksized with Custom made Lee Collet Die which sizes to .325" OD, which gives me a .003" neck tension. Annealing helps a lot. I now have more satisfying groups. I will compete this summer.
    I made myself a benchrest gunstock out of walnut, bedded using both JB Weld and pillars which improved accuracy a lot. As much as I hated this caliber, as much I love it now.
    Next time I need to form more brass, I'll give fireforming 6BR to 30BR directly without bullets a try .
    Thanks to all for their tips; it sure helped me a lot.
    Dan
    Last edited by danyboy; 04-26-2021 at 03:20 PM.

  14. #44
    Join Date
    May 2010
    Location
    Drummondville, QC, Canada
    Posts
    50

    Case length plug

    [QUOTE=Al Nyhus;835615]Amen! I have a bunch of case length plugs made from 12L14. -Al[/QUOTE
    PM sent to you.

Posting Permissions

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