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N133 in 6BR results

bpostbpost Member Posts: 32,221 ✭✭✭✭
This is the first testing I have done in the ENCORE 6BR using N133 powder.
There was a wind issue today that I am not good at reading but here is what I got.

75V-maxes 29.8gr N133
3101 FPS avg
44.57 ES
11.74 SD
HOT load. group was over 2" for 10 shots.

Nosler 70 BT 30.4gr N133
3171 FPS avg
26.65 ES
8.12 SD
Group was 1" for 10 shots, nice and round with three "flyers" that look like wind drift to me.

Nosler 70 grain match bullet
same load as above
3121 FPS avg
28.23 ES
SD 11.00
I shot the above bullet into two different five shot groups, one is a .372!!
This load is ABSOLUTELY MAX for my gun in cool temps.

Every load above was showing some level of primer cratering. Loads are going to be reduced further to see if that helps. Needless to say I am happy with the MV from the N133, thanks nononsense.

Any suggestions for reducing the ES and SD??


  • nononsensenononsense Member Posts: 10,934 ✭✭✭✭
    edited November -1

    Wind is always our nemesis when we want those itty-bitty groups.

    First, what OAL are you using and how close to lands are you seated in this chamber? Is this a BR Norma chamber or is it the standard Remington chamber?

    Cratering can be caused by high pressure generated by several sets of circumstances, hot loads being one set. This is always the first thing to consider but I also suggest that you look at the firing pin hole and see if it is 'significantly' larger in diameter than the firing pin itself. If you take the Encore apart and measure both, so much the better. Oversize firing pin holes can give the indications of cratering when the problem is the hole or the pin diameter. This shows up in Mausers frequently when the military M98's are converted to civilian cartridges and run at the higher pressures. We normally bush the firing pin hole then drill and ream a more exact hole to match the firing pin. Something to look into.

    The higher pressure is certainly possible since my data is based on bolt action rifles with Match chambers and your chamber probably isn't.

    ES and SD:

    I was working with a long range shooter 2 years ago and he had some outstanding targets that he had shot at 1,000 yards. I mean really competitve targets. But he was using a chronograph (good man) and generating all of the data that his chronograph was capable of producing. He was spending a lot of time trying to tuning his loads to reduce the SD and ES, all the while using up barrel life and not improving his targets or those numbers significantly. My response was to switch primers or powders and start over with the testing or ignore the numbers and love the targets. There are just those occasions where the numbers become less important than what the bullets are doing on the target.

    It may be that the combination of rifle, chamber, cases, bullets, primers and powder will continue to yield those numbers but if they also continue to yield good groups, why worry about it? One thing I will suggest is to switch Primers. This can be a major source of problems when trying to reconcile these numbers. It is also possible that your combination doesn't like the N-133 powder... I would shoot some primer tests first and see what happens but start with slightly reduced loads for safety's sake.

    Post the results when you get some if you have the time. Love that 0.372" group!

  • mrbrucemrbruce Member Posts: 3,374
    edited November -1
    Hurry up and shoot up all those bad bullets, and get on with testing those awesome 80 grain Fowlers in that POS Encore !
    Try some N135 too while your checking out those 80"s, and some RL-15 too while your at it.
    CCI 450's are the primer to use in a 6br.
    I've had some luck with the Russian Red's also....
  • bpostbpost Member Posts: 32,221 ✭✭✭✭
    edited November -1
    Well Guys this batch of brass is the batch that had the shoulders pushed back a bit by a improperly adjusted size die....MY BAD.

    I will try some of the Commie PMC primers, I seem to have a box of them here for some reason [:D][:D]

    nononsense my chanber is the 6BR REMINGTON, as marked by bullberry on the barrel, sure would have been nice if they had the neck size marked too!.

    I am going to retest with the PMC primers while making sure I am about .005 into the lands.

    I'll post the results when complete

    Then I will use some of those fancy-dandy Fowler bullets to see what she can really do.[:)][:)][:)][:p]
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