Results 1 to 7 of 7

Thread: Privy cases, high pressure on starting load.

  1. #1

    Privy cases, high pressure on starting load.

    Hi Guys,

    Has anyone found issues with high pressures at start load when using privvy partizan cases (.243 win). Has anyone found / measured the internal capacity of privvy cases and found them to be slightly smaller than other makes?

    For a full explanation please read details below. Sorry if its a bit much but still a relative novice to reloading and trying to understand more.

    Had started to get split necks on my Hornady cases. I moved on to my Privvy Partizan cases, as are my largest batch of cases that are already re-sized and trimmed to length (2.0350"). I have been loading 58gr Vmax for .243 win with 47.5 gr H380 with COL of 2.600 which is the minimum recommend COL.This load was worked up from start load and had no issues only stopped at 47.5gr as grouping was good. Now book lists start load of 46 gr to max 49gr with above combination. As I changed cases I started with lower amount than I had been using, 46.5 gr. Found bolt stiffer than normal to lift once fired. Have tried 46 gr and still have same effect but not quiet as stiff. When I re-chamber these fired cases the bolt is stiff to close, however if I re-chamber any other fired case all is as should be. I have measured the privvy cases just above the head and get a measurement of between .4705 - .4720 all other makes of case are max .4705 or less ( should be .470 ) hence the stiffness of the bolt I guess.
    I had been advised that changing only 1 component in a tested load should not cause any real issues, other than grouping may be effected.
    Has anyone had similar issue.
    I have some other makes of fired cases with primers in and have worked out the case capacity by filling with water. Average of H2o capcity seems to be
    Hornady cases Ave 55.4 (have been full length re-sized and trimmed several times.)
    Privvy cases Ave 54.7 (cases in question 2nd firing)
    Fiocchi cases Ave 54.6 (1st fire
    Federal cases Ave 54.6 (1st fire)


    So the hornady cases seem to have a greater capacity than all the others I have checked. Hence I suppose should have higher pressures in other cases for identical load and COL. Suggestions please on best way to proceed on developing load. Should I increase the COL to reduce the pressure and start at minimum load ? Some of the other cases I have did not require trimming after FL sizing so I guess there internal capacity could be less, so should I always increase the COL slightly than that list as min COL?

    Thanks

  2. #2
    cross reference powder charges from more than one data souce and check your powder is the right one used against referenced loads. Also check bullet weights against data, seen 180's loaded on 130 data before in 308's because the bullets were hand-me-downs in the a non original box
    Last edited by Paul at Fechan; 08-10-2014 at 15:14.

  3. #3
    Just trying to find out more,
    Are you getting head damage to the case's ? as if you are wiping off the lettering , this would say overcooking the load , tight loading would say its a head space thing, tight extraction more like over pressure , I dislike privvy brass as its thick and a hard brass , what if you load the same in another but not privvy made case ?. before your Hornady brass let go and had gone to hard did you have the same fault ?

    If you have no other brass to test drop me a pm as i have lots of .243, i can let you have some F.O.C be Norma or Sako
    I am in ss2, Essex.

  4. #4
    Quote Originally Posted by charlieboy-shooter View Post
    ....I had been advised that changing only 1 component in a tested load should not cause any real issues, other than grouping may be effected........
    Poor advice in my opinion. I work up a load for each brand of brass that I use. Regards JCS

  5. #5
    I keep a table of case weights which says that in .243 Hornady are consistent at 163 - 164grs, but Prvi are not as they range from 172 to 182 with the mean around 178.
    The character (temper?)of each make is different - Hornady brass is thin & hard whereas the cheaper Prvi is thick and soft so expands & swells at the head quicker ... so turning the bolt is usually stiffer. Collet neck sizing is usually limited to twice-fired only cases in Prvi, then the FLRSZ dies come out.

    I've noticed this in .223, .243, 6.5x55, and .308 so far. I usually use Prvi for working up loads from scratch then switch to more expensive lighter brass for the final product. I've no idea whether the dearer stuff is really any better TBH. I don't think you're getting excessive pressure - this is just a characteristic of the brass & that's how it is.
    If I'm going to be accused of it then it's just as well I did it.

  6. #6
    Thanks for the response guys. To follow up on some of the comments.

    Paul F, yes powder & data has been checked and Powder & bullets weighed on 2 different scales and are as should be.

    Paul o', the letters are still clear on the case but the primers are flatter. The un-fired cartridge was easily chambered and bolt easily closed, as are other makes. Only becomes stiff once fired and that includes re-chambering the empty case, then bolt is stiff to close and relift. No did not have any issue with the Hornady cases.

    JCS. I know that now but is also why I did not just reload as for the Hornady cases, lesson learnt. My 1st time from going from a known load to change of case.

    Sinistral, I had not considered the different hardness of brass and its effect. I have since found 3, once fired factory loaded privvy cases that I have not done anything to and when re-chambered the bolt is stiff on 2 of these too the 3rd case has nny stamped, which was fired by my gun but I had removed all these nny cases from reloading as I only had a few of these. I have weighed all my once fired brass with primers in and checked the internal capacity. Yes, the weights of the different makes of cases do vary but other than the Hornady there internal capacity of the others I checked seem similar.
    Last edited by charlieboy-shooter; 09-10-2014 at 12:08. Reason: to clarify that it is onlu ppu cases and not nny cases I am using

  7. #7
    [QUOTE=charlieboy-shooter;857846]Thanks for the response guys. To follow up on some of the comments.

    Paul F, yes powder & data has been checked and Powder & bullets weighed on 2 different scales and are as should be.

    Paul o', the letters are still clear on the case but the primers are flatter. The un-fired cartridge was easily chambered and bolt easily closed, as are other makes. Only becomes stiff once fired and that includes re-chambering the empty case, then bolt is stiff to close and relift.


    Q(No did not have any issue with the Hornady cases.)


    ? feel you have solved your own problem mty dump that brass get some good stuff and carry on ,as said if you need some i have some here used once or get hold of spud off the site and buy 100 new of you choice say lapua as you can load them from new and fire form without any fuss .if you need help drop me a pm if you are local and i will be happy to walk you though the steps no probs.

Similar Threads

  1. For Sale High pressure air gun compressor. Make: Fx.
    By riflehunter583 in forum Other Shooting Equipment
    Replies: 0
    Last Post: 30-06-2014, 17:23
  2. starting load 22.250
    By stav in forum Ammunition, Reloading & Ballistics
    Replies: 2
    Last Post: 23-11-2013, 16:40
  3. Recommend me a starting load
    By Wingy in forum Ammunition, Reloading & Ballistics
    Replies: 20
    Last Post: 28-12-2012, 22:50
  4. Pressure signs in rimmed cases?
    By Adamant in forum Ammunition, Reloading & Ballistics
    Replies: 8
    Last Post: 20-06-2012, 14:19
  5. Starting load for 308 - 150gr SST's with Varget
    By Win Mod 70 in forum Ammunition, Reloading & Ballistics
    Replies: 8
    Last Post: 29-07-2011, 06:27

Posting Permissions

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