In order to participate in the GunBroker Member forums, you must be logged in with your GunBroker.com account. Click the sign-in button at the top right of the forums page to get connected.

7.5 Swiss from 284

dennis53dennis53 Member Posts: 86 ✭✭
I am having trouble getting ammo to chamber properly in my K-31 Schmidt-Rubin. They are reloads from 284 brass run through RCBS dies. I full-length resize, but the shells seem to get hung up at the very base of the cartridge near the rim. Any solutions?

Thanks,
Dennis

Comments

  • nononsensenononsense Member Posts: 10,928 ✭✭✭✭
    edited November -1
    Dennis,

    The base or head size of the U.S. .284 Win. brass should measure 0.500" in diameter while the 7.5 Swiss will probably be about 0.493" in diameter. Your sizing die may not be turned down all the way in order to resize the base or the die just may not be ground small enough to do that. It has been mentioned before that there can be some variances in the Swiss chambers, enough so that your brass may not fit without having a specific sizing die made, something along the lines of what's called a 'small base die'.

    Best.

    You also need to check the various lengths of the brass that you're using, neck, shoulder, body, et al.
  • PearywPearyw Member Posts: 3,699
    edited November -1
    You can buy 7.5 Swiss brass from Graf's for about $28 a hundred. I have used their brass in a set of Lee dies without problems in my K31 and my 1911 Schmit-Ruben.
  • nononsensenononsense Member Posts: 10,928 ✭✭✭✭
    edited November -1
    As long as we are talking about chamber variations, here is a photograph of 2 CerroSafe castings from different rifles:

    7.5Swisschambercasts.jpg
  • dennis53dennis53 Member Posts: 86 ✭✭
    edited November -1
    Thanks for the good advice and very interesting photos.

    So what brand of (factory) die do you guys use
    to form the 7.5 from 284?


    Thanks,
    Dennis
  • jonkjonk Member Posts: 10,121
    edited November -1
    I use Lee dies and have never had a problem with the .284 brass, but every set of dies and guns varies slightly....

    "...hit your enemy in the belly, and kick him when he is down, and boil his prisoners in oil- if you take any- and torture his women and children. Then people will keep clear of you..." -Admiral of the Fleet Lord Fisher, speaking at the Hague Peace Conf
  • mazo kidmazo kid Member Posts: 648 ✭✭✭✭
    edited November -1
    Try chucking the brass in a drill press and filing a couple of thousandths off the head, where it is binding. Emery

    "Well done is better than well said"
    Ben Franklin
    NRA Life
    NMLRA Life
  • sandwarriorsandwarrior Member Posts: 5,453 ✭✭✭
    edited November -1
    Dennis53,

    I've waited a while to respond to this as I am working up loads for the 7.5 Swiss in my K-31's. If I can give you a good temporary resource for 7.5 Graf brass it is www.gunstop.com this will save you from fireforming or forceforming the .284 Win brass. It also has the right base(head) for the K-31 rifle. I have really started to like this round. keep in touch on your progress.

    We have the second amendment so that all the rest are secure....UNK>
  • dclocodcloco Member Posts: 2,967
    edited November -1
    I resisized my 284 Win brass Wednesday night, shot at the range last night...no problems at all.

    Cases are now completely fireformed (shoulders at a slightly different angle than the 7.5x55 swiss round.

    NO extraction or feed problems either.
Sign In or Register to comment.