How many rounds to develop a load?

Discussion in 'Reloading' started by Nobody, Apr 3, 2009.

  1. Nobody

    Nobody Well-Known Member

    May 15, 2008

    Been a member for sometime though I rarely post. Do a lot of reading though.

    I have a 264 Win Mag Sendero II. It's got a 1/9 twist, standard Remmy trigger though it's all been worked over by Clarence Hammonds. I'm trying to develop a load for it using 140 SMKs. I'd called Sierra and gotten a load range of something like 55.?grs - 62?grs of IMR7828. I can fire a couple of rounds and have them touching and the next three rounds are 3/4 of an inch out. Typically, I start at mid-range - I feel that's a safe thing to do though with 264s you gotta' be careful because they generate pressure spikes with even slight changes to load weight.

    Anyway, I've got through like...25 rounds and I'm still no where near where I think this gun should be. My question, as the title suggests is, how many rounds should I reasonably expect to have to shoot while developing a load?

    And by the way, if anybody has a good, safe load using IMR7828 or IMR4831 please let me know.

    Thanks in advance.
  2. boomtube

    boomtube Well-Known Member

    Oct 8, 2007
    Don't think a .264 Sendero is unique in load development. Using the "ladder method", I can quickly eliminate any load ranges that don't work and focus on the narrow range that does work pretty quickly. After finding the best shooting load I do the same type tests for seating depth. If you are unfamiliar with the ladder method, Goggle it, or the look for the Audett method, for instructions.

    IF a rifle is capabile of shooting well AND likes the chosen bullet/powder, I typically find the best combo within 40 to 60 rounds, in two or three trips to the range.
    Last edited: Apr 3, 2009

  3. Kevin Thomas

    Kevin Thomas Well-Known Member

    Feb 16, 2009
    So you have 25 (!) rounds downrange and you STILL don't have a load!?!?!?

    Sorry, I couldn't resist. Hey, these things take time, and a lot of reloaders don't want to hear that. Don't know why, since a day at the range sure beats a day in the office. Unless you're dealing with something like an M14/M1A or and AR Service Rifle, you're going to wind up spending time developing your loads. With these, the loads are so well known and so well proven that it's almost a waste of time trying to reinvent the wheel, if you get my drift. Back when everyone shot M14s, you didn't work up your load. You stuck in about 41 grains of 4895 under a 168 MK, and you went to the range. Guaranteed, 95% of the other guys on the line would be using the exact same load. If it didn't shoot, there was something wrong with the gun, period. AR Service Rifles are much the same these days, with either Reloder 15 or Varget (about evenly split) under a 77 and/or 80 Match bullet. Done, and everyone knows it'll work, or your gun needs help.

    Hunting rifles are a different story, especially with cartridges that don't see the volume of firing that the others do. That should be part of the fun of them, but it does take time and effort. I'd recommend trying at least threde different powders in the 264, probably at least two or three different powders, and whatever bullets you want to use. Change only one component at a time, and record your results. There's a process to this, and it will take some bad groups to see what's going on. Don't get discouraged, because at some point you shpould start seeing improved groups. Narrow in on that, and start making smaller refinements at that point, again, changing only one variable at a time. You'll see the improvements start taking shape, and know you're getting closer. And at some point, you should actually realize that you're having fun and getting excited about all this. Once you get there, congratulations, and welcome to handloading.

    Yiou've already got 7828, but I'd suggest also trying H1000 and Retumbo. I'm sure some other folks on here, ideally who've had some experience with the 264 Win Mag, will have some input for you as well.

    Kevin Thomas
    Berger Bullets
  4. britz

    britz Well-Known Member

    Mar 11, 2007
    Hello Nobody,
    Just because joe schmoe has a load that works in his rifle, doesn't mean it will work great in yours. I'm not as much an expert as many on the site, but I often will go through 50 rounds or more just to get in the ball park. There are so many powder bullet combo's to try it'll make your head spin. However, if you are experiencing fliers with many loads and can't find a good one (after you have tested many many more) than I would invest in a bedding job for your rifle. Are you sure your scope is good? Are you weighing every load? How is your seating depth? are you measuring the bullets from the ogive? are they within .002 in length (a number I pulled out of a hat for example). how is your runout (it would have to be real bad to notice on a factory rifle IMHO).

    I have a savage 22-250 that I have finally gave up on getting better than inch groups with... after about 40 test groups (ya that is a little overboard but I was learning lots about reloading practices too ;) as the saying goes.. learn something new every day.

    Good luck.
  5. friendlyfireisnt

    friendlyfireisnt Active Member

    May 5, 2006
    I think Kevin is spot on, no surprise.

    I haven't been reloading a long time, just a few years, but I have had pretty good luck so far. I would like to think that part of my success has been that I typically spend hours in research prior to starting load up.

    Lucky for me, the cartridges I load for have a ton of information available for them, and decades of established quality loads, and there shouldn't be many surprises.

    Even with my .30-06 and .270, where I had a real good idea where I was going to end up, I still expected more than 25 rounds. It takes time, and it takes some work to find what works. With my .30-06, I went through several bullets, and 3 powders before I found two good performing loads. My .270 Sendero seems to be a bit easier so far. Part of that is I went with the old standard load of H4831 and 130gr bullets, and the other part is that I think this rifle will shoot almost anything well.

    I shot about 150 rounds doing load development on my .30-06, and about 45 rounds with my .270, which I am still finishing my load workup with. I actually got two loads on that one, but I was lucky.

    Way too many variables to expect to have a winner within 25 rounds on every try.

    One of these days, I am going to try some Berger bullets.
  6. Nobody

    Nobody Well-Known Member

    May 15, 2008
    Britz to answer a few of your questions, the rifle was overhauled top to bottom by Clarence Hammonds, a well-known benchrest gunsmith. The only thing I didn't have him do, and this was a mistake on my part, was to replace the trigger. That mistake will be rectified in the next week or so when I take the rifle out and have him do it. I'm using a Leuopld Mark 4 6.5 - 20x50 scope so that shouldn't be a problem. He worked on a 308 tactical rifle I have and that thing shoots 5 shot .3" groups when I'm doing my part.

    I weigh every load twice. Although I don't go for fancy cases - I just use Winchesters. And I don't neck turn them. I do full-length re-size though.

    I've used two types of primers so far in my experiments CCI-BR2 LRs and Winchester Magnums. I've heard there IS difference between LRs and magnum primers and I've heard there ISN'T a difference. When I measure COAL, I'm measuring off the ogive. Determining the COAL was something of a guessing game and in the end I just seated the bullet long and kept shortening it until I didn't get any land marks on the ogive. My standard is to keep the COAL consistent to .001.

    Friendlyfireisnt your comments about so many variables is the TRUTH. I get demoralized when I think that the problem could be my powder choice OR the primer OR I may not have the correct COAL or the bullet weight may be wrong for the twist rate. Heck, even the crappy trigger could be the problem.

    Thanks for your comments.
  7. britz

    britz Well-Known Member

    Mar 11, 2007
    The only other thing I can think of right now would be to weight sort (volume sort) your win brass. I seem to always experience a range of about 4 grains per lot in weight. perhaps try a different bullet weight or brand. I'm not a BR loader by any means, but when I develop a load for a rifle I start out with usually 3 different bullets and at least 2 or 3 different powders. When that fails, I switch to a lighter or heavier bullet and do it again. Good luck!
    Last edited: Apr 4, 2009
  8. J E Custom

    J E Custom Well-Known Member

    Jul 29, 2004
    I use a chronograph for the process of eleminating bad loads and don't worry about group
    size in the begining.

    It goes something like this=

    First I select the bullet I would prefer to use.

    Then I look at loading data for powder that has maximum performance and velocityat 100%
    case density.

    Next I load 3 rounds ,each with different powder charges starting midrange and moving
    up to Max listed load by .5 gr increments.

    Repeat the process with the next best powder listed.

    Now its off to the range to test the loads. Make a log and keep very good records on all the
    test loads (Even the bad ones) they will come in handy later on.

    Start with the lowest loads and work up using the crony.

    I eleminate based on bad SDs sometimes with only 2 shots and save the other rounds for
    fowling shots or pull the bullets and reload to save the brass from to many firings.

    Once you find good Standard deviations then zero in on powder charge,seating depth,primer,
    even bullet type (Same weight).

    With out good SDs you will never have good groups at long distances because this is the load
    burn consistancy and with velocity changes vertical and horizontal stringing will drive you crazy
    even if everthing else is good .( Like bedding ,barrel twist ,trigger pull ,ETC.

    This process has saved me many rounds of testing and lots of brass over the way I use to do
    my load development.

    So now I some times luck out and find a realy good load after only25 or 30 rounds down the
    tube but sometimes tweeking to get the very best load can add another 20 or so rounds to
    the process.

    Be patient and it will come.

    Just the way I do load testing
  9. Coyboy

    Coyboy Well-Known Member

    Jan 30, 2005
    Did Clarence give you a report on what he found in the bore?

    Was the chamber and throat concentric with the bore? doubt it but maybe you got lucky. Was the rifling defect free, from end to end? I assume he skim coated the action to stock and recrowned the muzzle? Lapped the lugs?

    It helps to know some of the challenges you need to overcome.

    Before I did any load work I would do my best to brake in the factory tube. Minimum 10 shoot and cleans 20 would be better.

    I would pick an accurate bullet, work with that and 2 sutable powders to start.
    Find your max oal to touch lands and back off .025". Load up 7 rounds of each with a powder charge that falls dead center between book starting charge and max charge. With a bone clean bore fire two foulers off the target and the next 5 for group, clean and do the same with the load of a different powder.

    If one powder shows promise, work with the charge weight up or down a 1/2 grain or seating depth .010 in or out.

    If those 25 or so bullets don't give you a direction to head, re load the brass, neck sized only and use the exact same oal and powder weights as the original 2 loads. Sometimes the neck sized brass will shoot in the same load that wouldn't shoot in a piece of new brass, somtimes it may be exactly the opposite.

    This will give you a good start to a promising load, If you get to 200 rounds and nothing meets your needs, get a new barrel!!! OR save yourself the frustration and get a new barrel now.