Load Tuning By Jerry Teo

Discussion in 'Technical Articles - Discussion' started by ADMIN, Sep 14, 2009.

  1. ADMIN

    ADMIN Administrator

    Mar 6, 2008
    This is a thread for discussion of the article, Load Tuning, By Jerry Teo. Here you can ask questions or make comments about the article.
  2. jmden

    jmden Well-Known Member

    Nov 2, 2003
    Thanks, Jerry, for sharing your experience here. Great article.

  3. ejones338

    ejones338 Well-Known Member

    Jan 29, 2009
    Thank you for the lesson.

    For some reason load tuning is still overlooked by some. Many people that I know still think load tuning is walking it up to a max velocity, and then blaming accuracy problems on the rifle.

    Your method is much like my own, and it is a must with any rifle.
  4. liltank

    liltank Well-Known Member

    Nov 3, 2008
    I've tried a variation of this method with good effect. I generally use a full 3 rnds, but I guess I should start going out further to make sure I am on. Thanks! By the way, whats a Mystic? I see a 7mm and 338 Mystic!


    PM me if you would as not to get off subject on this topic.
  5. angus-5024

    angus-5024 Well-Known Member

    Jan 22, 2008
    I learned alot from your article Jerry, especially about the vertical vs. horizontal groups, makes sense. I have been wasting ammo on poor attemps at load developments. I did luck out with .5MOA groups, but i find that they open up with temp changes, guess its back to the bench for me.

    HUAINAMACHERO Well-Known Member

    Oct 16, 2008
    Jerry thanks for the teaching.
    Very interesting article, will try your method and looks loke will save some ammo.
    Thank you.
  7. foreign

    foreign Well-Known Member

    Jun 26, 2008
    thanks Jerry. good to learn that what i was doing was kind of right. but was doing it at 100yrds. will take it out further at recheck. the clocking concept is a new one and make heaps of sence. now just to look at old target and ill recognise it. thanks again.
  8. jonoMT

    jonoMT Well-Known Member

    Nov 14, 2007
    Great article...will help me streamline this process. I hadn't thought before about doing the load testing out at 200-300 yards (until I have a load I already thought was good at 100).

    What's your opinion on combining testing with rifle break-in? My guess is that doing it during the break-in process won't necessarily yield the best results. But also that it can't really hurt. I figure the more practice you get carefully handloading the better and might as well get the rifle dialed in as well as I can early on.

  9. phorwath

    phorwath Well-Known Member

    Apr 4, 2005
    That process is very similar to the process I've settled on to minimize time, expense, and loss of barrel life. I also add a chronograph to the process because if I'm not also getting low ESs and SDs, then I know the load won't perform at long range. The two shots per load during the workup process provides a first glimpse at ES, and I have found that low ES will often coincide with the nodes. I wouldn't say every time, but probably more often than not. One other difference. I shoot at 300 yds rather than 200 and select wind-free or low wind conditions. My range is somewhat protected by trees on both sides and wind hasn't proven to be any big issue for me at 300 yds. Besides, I'm most interested in loads that shoot with minimal vertical separation, as has been stated.

    My cartridges typically have larger powder capacity than the ones mentioned here, and I'll increase powder increments to 0.5 to 0.7 gr on the first round of incremental powder charges.

    For those shooting heavy-for-caliber high BC bullets, refer to the below thread for an explanation as to why farther distant load development ranges, 300 to 500 yds, are better for truely long range load development. The high BC bullets out of fast twist barrels often take some time to settle down, and loads that shoot 0.75 moa at 100 yds may actually shoot less than 0.5 moa at 500-1000 yds. Here's the link:


    Oh -lightbulb- one last point. With the larger cartridges, it's important to mention that a person needs to keep the barrel relatively cool during the load shooting process. Kind of a pain in the rear. But if you want to have confidence that your groups will represent the loads cold bore accuracy performance in hunting conditions rather than rapid-fire conditions, I think it's pretty important. Also, with any thinner-tubed barrels, accuracy will often go to pot after the third shot if you don't allow the barrel to cool down. Then all you're doing is wasting time and ammo - because none of the groups will yield an inkling of your rifle's performance potential with any of your test loads.
  10. MontanaRifleman

    MontanaRifleman Well-Known Member

    May 21, 2008
    I'm not sure if Jerry will agree with me on this, but I do break-in the barrel during *initial* load development. I also fire form the brass in the process. By "initial" load development, I mean shooting increments of powder charge while looking for max. Shoot one at each increment and clean. I will load several strings with a different powder/bullet combination. Then I start looking for my nodes.

    It probably doesn't fit Jerry's process very well, but if you are one to break-in your barrel, it should be done early and it seems like a good time to find where your max is.

    BTW Jerry, very good article.

  11. cdn shooter

    cdn shooter Active Member

    Jan 28, 2009
    Thanks for the lesson Jerry
    I needed a new load for a work trip taking me into northern canada(always have the rifle this time of year) and with large elk,moose I needed a tough bullet. I picked up a box of noslers loaded in increments took it to the range fired 18 rounds, saw both nodes went home loaded 30 rounds in the middle of the second node, went back to the range put 2 bullets into the middle of the 300 400 500 steels. Just like that new very accurate load.

    Junior Reloaders pay attention this instruction is the real deal.gun)
  12. tlk

    tlk Well-Known Member

    Apr 11, 2008
    From the article it looks like there are five constants to get reliable data: neck tension, cartridge OAL, powder, primer, and bullet. The only thing that changes within the loads is the powder charge and the only thing that you should be witnessing is the effect of the load change, everything else constant. This method is only used after you have chosen a powder/bullet combo that shoots reasonably well initially in your rifle, correct?

    Last edited: Sep 23, 2009
  13. Gene Jr.

    Gene Jr. Well-Known Member

    Feb 6, 2009

    I can't answer for Jerry, but my response is that you are correct in your understanding. There are a lot of choices that can be made. BUT and it's a big but, there are some easy to determine factors. Availability and personal preferance will determine most starting points. Available brass, bullet for correct application, available powder to provide desired velocity, OAL determined by magazine or set to lands... Start with what YOU want to shoot and then adjust as the gun tells you what IT wants to shoot. If your desired components don't work, change a variable and try again. Record all changes! The gun will tell you what it likes.

    I personally choose a minimum velocity goal and then work to find a node at or above that. I have found some of my best accuracy loads at the slower node. Nice for punching short range paper but don't serve me well for any kind of long range. I currently hunt big game with a 243 win and a 270 win. Not big boomers, so I like to run them as warm as possible and still have great accuracy.

    Good luck and have fun!
  14. jmden

    jmden Well-Known Member

    Nov 2, 2003

    What scale do you use/recommend? Why?