Way in or way out ?

Discussion in 'Reloading' started by Jimm, Feb 6, 2006.

  1. Jimm

    Jimm Writers Guild

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    I have had /have loads that will shoot in the ones and twos at 100 yds. that are being jumped 40 to 50 thou.

    Anyone else have some like that ? I have heard from folks in the br circles that there can be a way in and or a way out seating depth for each load that ios accurate in a particular gun.

    undergoing severe hunting withdrawal pains at this time , please help /ubbthreads/images/graemlins/crazy.gif

    Jim B.
     
  2. Ballistic64

    Ballistic64 Well-Known Member

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  3. green 788

    green 788 Well-Known Member

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    Jimm,

    It does seem that just about any load recipe will have various seating depths which will allow the groups to form well.

    Often, benchrest shooters really don't know the "whys" behind what they do. Like a top level Nascar driver, he's great at what he does, but he really doesn't know why this particular cam works better on this particular track. He only knows that it does. This is why we often get a mish-mash of blather from BR circles with regard to seating close to the lands.

    When I hear that a particular bullet "likes" a certain amount of jump to the lands, I am skeptical. In nearly every situation, you can make that bullet shoot well at magazine length. Folks who believe that bullet X needs a .020" jump to the lands will begin with that seating depth and adjust the powder charge until they get tiny groups. They conclude that indeed this bullet does "like" a .020" jump.

    Barnes and perhaps some other makers have found that some of their bullets do better when loaded close to the lands. Again, they tell you this without telling you why. /ubbthreads/images/graemlins/laugh.gif Likely, the subject bullets are difficult to seat straight, and they end up with higher than average runout (perhaps the ogives are not compatible with typical seater die buttons). The closer seating to the lands may allow the bullet to be deflected to center as it engages the lands, rather than smashing into the lands and engraving off axis--as might happen with a deeper seat.

    I think if you seat the bullet straight, and your case neck and chamber are concentric, you can seat deeper and get great accuracy.

    Changing the seating depth changes the barrel time. Bullets seated at different depths will be released on various points on the vibration pattern at the muzzle.

    [​IMG]

    As you can see from this diagram, there are likely two different accuracy nodes on a barrel's vibration whip. Altering the seating depth will move the bullet's release to different points on this (typical) figure 8 pattern. As you seat deeper and deeper, or shallower and shallower, you'll move the bullet around on this pattern. Ideally, you will want the bullet to release as close to the narrow loop's endpoint as possible. Here the muzzle is slowing, almost to a stop, before it changes direction. Bullets with muzzle velocities within about 25 fps of ES can still be released in virtually the same point in space--a good thing.

    If you're releasing your bullets on a "straightaway" in the figure 8, they may string on the target--even if the ES looks great on the chronograph. This is why it is always best to let the target over-rule the chronograph in situations where they don't agree. /ubbthreads/images/graemlins/wink.gif

    The vibration whip is not to be confused with the main barrel shock wave, as identified by engineer Chris Long. Chris Long's pages can be linked by going to my website and scrolling to the bottom of page one. That's a different thing entirely, and OCW load development should be used to identify the "coarse tune" powder charge, and then seating depth adjustments should be used to make the final tweaks to the load. Most guys--even vaunted BR guys--get this backwards. They begin with a fixed seating depth (yeah, because so and so said this bullet "likes" this seating depth /ubbthreads/images/graemlins/smirk.gif ) and they manipulate the powder charge to make that seating depth work. This is much like beginning with a particular ignition time setting on a racing engine, and then changing pistons until you get the timing to work. /ubbthreads/images/graemlins/tongue.gif /ubbthreads/images/graemlins/laugh.gif

    So yes, there are indeed different points of seating depth that will work just fine--for the reasons mentioned above...

    Dan
     
  4. Jimm

    Jimm Writers Guild

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    Mr. Ballistic,

    You are a menace /ubbthreads/images/graemlins/laugh.gif to good marital relations that is . /ubbthreads/images/graemlins/grin.gif Yes , varmint season is still in here , and yes , I want one of them new Foxpros with speakers on each end and a plug in for the remote decoy. But no ! its not happening this winter /ubbthreads/images/graemlins/frown.gif How far will the remotes work on those rigs . A very good friend of mine has one but he won't let me get more than a hundred away from it /ubbthreads/images/graemlins/tongue.gif Guess hes afraid the varmints will carry it off.

    I hope to have mine by this time next year and thanks for the direction ,

    Jim B.
     
  5. Jimm

    Jimm Writers Guild

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    Green 788,

    Thanks for the reply. I realize that you have experience with benchrest folks that lead you to make the observations you have shared with me .I reckon complacency is not a commodity that is'nt universal. That is to say, it exists in all disciplines .

    I think the think the main reason I posted the thread was boredom /ubbthreads/images/graemlins/blush.gif However , I did want to poiunt out that I never hear of someone sharing a load that is killer in their rig that is also noted as being seated "way in " .

    I'm sure you know people like Henry Childs that are grand old men in the paper shooting disciplines that are very knowledgeable and do not settle for a "formula " but press on to understand and quantify the forces at work . I will never reach any place close to their understanding of the forces at work . Especially as related to current components / equipment and ther performance at the firing line . That doesn't stop me from asking and assimilating to the best of my ability . Indeed , that is probably a good thing because that is exactly why I will not be a " burnout " . It is my observation that that happens more often at the top of the game .

    I am an avid hunter but I think that paper punching will serve me well in that ar3ea and besides ! I like to pull the trigger and send one downrange......then two, then ....well you get it /ubbthreads/images/graemlins/grin.gif

    BTW, What do you do and where do you live ? I want to know so I can try to plan a trip past your place while going to hunt something somewhere else so i can hunt something in your area that you will tell me where to go and do it and then I will then /ubbthreads/images/graemlins/blush.gif /ubbthreads/images/graemlins/blush.gif /ubbthreads/images/graemlins/blush.gif Sorry , my wife just came in and said " honey you're doing it again " ( how does she know ? )

    p.s. green 788 , your rem 788 is green ? hence the moniker ? Jim B.
     
  6. Ballistic64

    Ballistic64 Well-Known Member

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    I do my best,even my wife tells me that. /ubbthreads/images/graemlins/grin.gif
    The remote on the foxpro I have (532) is advertised to 700 yds under ideal conditions.I cant imagine why anyone would ever want that kind of range,but thats what foxpro claims.The farthest Ive ever set mine out was just under a 100 yds and worked great.Those dogs just dont stand still for very long though.I'll probably go out this weekend and call since weve had cooler temps and just got some snow.
    But for tonight I have to sneak a new model 7 in the house and scheme on the checkbook to get a deposit for an Alpine before they go off sale! /ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/cool.gif
     
  7. BountyHunter

    BountyHunter Writers Guild

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    OK, Green 788

    Talk about a mish mash of blather, that is the pot calling the kettle black.

    If you think BR shooters start into the lands with some types of bullets because they cannot seat them straight, you have been smoking some really good stuff. There is no way to put it other than to say that is an absolutely asinine statement.

    Guess who originally learned about tweaking your seating die nose to fit the bullet? Guess who started sorting bullets to ogive, guess who started metplat trimming, and other match proven techniques.

    A BR shooter normally start into the lands because we have only one way to go and that is out, rather than jump in and out of any other way as you prescribe on your site. Plus we are not limited to a mag OAL. BR shooters are extremely methodical in what they do and why and it is match proven vs speculation on an unproven theory.

    As for the gobbledy goop statement about BR shooters adjusting powder charge to make a certain seating depth work, YOU have it backwards and are totally wrong again. I cannot even imagine where you dreamed up such a statement!! We never use a fixed seating depth and adjust powder only. Basic BR techniques call for adjusting the seating depth last normally.

    You are deriding match proven techniques that you obviously know nothing about and are totally misinformed in almost every aspect based on the comments you made. Plus even if it was, it sure as heck works and is proven time and time again on the range.

    You do not have a clue about extreme accuracy and what it REALLY takes to get there if you believe that garbage you just printed. Oh sure, as you say "You can make a gun shoot well off the lands" which is taking mag gun and getting 1/2-1 MOA, which is the repeated OCW standard. Well that is not extreme accuracy by any stretch of the imagination. That and a $1 will get you a cup of coffee at a match and a quick trip back to the car to go home.

    Leave extreme accuracy techniques to people who do it vs deriding and theorizing.

    BH
     
  8. green 788

    green 788 Well-Known Member

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    We'll make this very simple BH. You tell all of us why seating against the lands works well when it does, and while you're at it, clue us all in as to why some bullets "like" a certain amount of jump.

    Presumably you have these answers, but in your zeal to hammer me /ubbthreads/images/graemlins/ooo.gif , you've inadvertently omitted them from your above post.

    I was not referring to BR shooters when I mentioned that seating close can negate the effects of runout. And I've never said that OCW load development is only good for 1/2 MOA. If you're gonna quote me, quote me right dammit! /ubbthreads/images/graemlins/smile.gif

    Jimm, drop me a PM... /ubbthreads/images/graemlins/smile.gif

    Dan
     
  9. green 788

    green 788 Well-Known Member

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    And one more thing... please explain the following:

    "A BR shooter normally start into the lands because we have only one way to go and that is out, rather than jump in and out of any other way as you prescribe on your site."

    I'll check back in the morning... /ubbthreads/images/graemlins/wink.gif
     
  10. royinidaho

    royinidaho Writers Guild

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    [ QUOTE ]
    undergoing severe hunting withdrawal pains at this time , please help /ubbthreads/images/graemlins/crazy.gif

    [/ QUOTE ]
    [​IMG]

    Gotcha!

    Yep, you're bored. Yep, every one has those kinds of things happen. Bet you can remember some really spectacular misses that there is no reason that you missed. /ubbthreads/images/graemlins/frown.gif Yep, me too. Gremlins is what I call them. They are not there all the time. Just randomly and unannounced. If I tho't different I think I would be really hard to be around and my head would be really pointed. I don't think my dog could even get along with me.

    I too was a benchrest shooter. Many moons ago. Had all the stuff. 40Xs, Hart barreled/Hart Sleeved, super hootie powdered scopes. Triggers in the ounces etc. Wasted a lot of summers doing that when I could have been harvesting something.

    At what distance are you shooting the 1.? 30 feet? /ubbthreads/images/graemlins/grin.gif

    If its 100 yds or better you're talkin about, you're either hanging out on the wrong forum or forgot you Paxil/Zanx or whatever. /ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/grin.gif

    Having said all of that, there are times when things come together. Your 100 yd aggregate is in the 3s, your 200 yd aggregate is when adjusted for 100 yds is also in the 3s. Your small group was no smaller than middle 2s. In Idaho's high desert that's plenty good to win a match regardless of who flies in to take advantage of the locals. /ubbthreads/images/graemlins/laugh.gif /ubbthreads/images/graemlins/laugh.gif

    My greatest day was during a br match there were two of us neck and neck. Shot the 200 first. We were pretty much tied. Way ahead of the pack. Through the 1st 4 100 yd targets were were still neck and neck. Both shooting bug holes. All other shooters were done and gathered in the gallery behind spotting scopes. Ken would shoot. Gallery would give a sigh of relief. Another in the group. I would shoot. Same sigh of relief. Ken's 5th shot went "in there". I could tell from the sounds of the gallery. I had one shot to go.

    Finally my rifle went bang! The sound from the gallery was one of dismay. My last shot was a full inch outside of the group. I went down in flames, they thought.

    They wondered why I was carrying a bit of a smirk when I should have bending the barrel around a post!. When the targets came back to be scored and were posted on the wall, all eyes were on me. What had gone wrong? I was still smirking, kind of like this /ubbthreads/images/graemlins/smirk.gif

    With the targets on the wailing wall, I ask the closest guy to my target what the color was around the hole. He looked at the target and then looked at me with a confused look and said <font color="red"> RED? </font>.

    Yep, I'd shot my first 100 yd fly. Would rather harvest something anyday than punch holes in paper. /ubbthreads/images/graemlins/grin.gif

    So smear some hamburger on your target and go shoot some snow flies, before this thread disrupts Len's living room. /ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/grin.gif

    Bye the way, I quit shooting BR that fall when HK came out with a semi-auto police rifle that would win an Idaho br shoot any day of the week shooting semi-auto from the magazine. /ubbthreads/images/graemlins/frown.gif
     
  11. green 788

    green 788 Well-Known Member

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    Somehow this old non-BR guy managed a fly as well... /ubbthreads/images/graemlins/laugh.gif

    [​IMG]

    And a lowly Savage shooting an OCW load at that... /ubbthreads/images/graemlins/ooo.gif /ubbthreads/images/graemlins/grin.gif

    Seriously, that 10FP has shot more than it's share of three shot bugholes. Not BR status, but not bad for a factory stick.

    Dan
     
  12. royinidaho

    royinidaho Writers Guild

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    Back on track,

    My experience has been and still is that Spire points (Hornady's) always liked to be jumped in. Sierras just a "little" off the rifling and can be varied quite a bit. Wild Cats are about like the Sierras but have been a llittle more accurate and less finicky for me.

    My experience is that the Hornady's when seated with the case mouth exactly even with the bottom of the crimping ring works the best. (I'll leave it up to you how long to make the trim length of the case. /ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/grin.gif) I think that's the secret.
     
  13. royinidaho

    royinidaho Writers Guild

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    [ QUOTE ]
    And a lowly Savage shooting an OCW load at that... /ubbthreads/images/graemlins/ooo.gif /ubbthreads/images/graemlins/grin.gif

    Seriously, that 10FP has shot more than it's share of three shot bugholes. Not BR status, but not bad for a factory stick.

    Dan

    [/ QUOTE ]

    Man, you're quick on the trigger. Sneaked in there between my posts and I wasn't dooddling. /ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/grin.gif

    I'll take credit for a better fly shot than yours. Your calibur was way bigger. My bullet weight was only 52 grains. /ubbthreads/images/graemlins/blush.gif /ubbthreads/images/graemlins/crazy.gif /ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/grin.gif
     
  14. Bart B

    Bart B Well-Known Member

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    This is an interesting thread. I'll throw in my observations to change the flavor of what's in this kettle.

    How far a bullet should jump to the rifling varies as much as what components to use that makes 'em jump. Most interesting is what the different shooting discipline's best shots use and how they determine what works best.

    The best test method to evaluate ammo for accuracy is one that is the most repeatable, has the most shots per group and has the best accuracy. It returns the barrel back to the exact same position held in the exact same place with exactly the same force or pressure.

    At the top of this list in first place are the return-to-battery machine rested rigs used in unlimited class benchrest competition, testing highpower match rifles and testing bullets at a bullet making company. Such devices are shot virtually untouched by humans. These rigs are used at ranges from 100 to 1000 yards and shoot the smallest groups. Groups are typically 5 to 20 or more shots or the average of several of them.

    In second place are benchrest rifles rested on sandbags untouched by humans except for the thumb and fore finger pinching the 2-oz. trigger to fire the shot. Again, groups are typically 5 or 10 shots or the average of several of them. And they're shot at ranges from 100 to 1000 yards.

    Third place (and very close to what's in second place) belongs to highpower rifle shooters slung up in the prone position. Although they shoot for score at ranges from 300 to 1000 yards, their 15- to 20-shot "groups" are mentally measured by how far the shot strikes from where it was called.

    Fourth place is relagated to varmint hunters who's 22 to 24 caliber rifles and ammo are tested off a bench. They hold their rifles against their shoulder gripping the stock's forend or toe with their off hand and the pistol grip with the trigger hand managing an 8-oz or heavier trigger. They test usually at 100 yards but sometimes at 200 or 300. Groups have more than 3 to 5 shots.

    Fifth place are folks shooting 25 to 30 caliber hunting rifles tested the same way as varmint hunters; 3- to 5-shot groups at 100 yards and occasionally up to 300; rarely more. Triggers are typically heavier as well as recoil.

    Sixth and last place belongs to folks shooting rifles greater than 30 caliber having heavier trigger pulls lots of recoil fired from the traditional bench setup used by those in fourth place. 100 yards is the typical test range and test groups have from 2 to 5 shots. These rifles are the hardest to shoot accurately.

    If one compares the components used and how they're assembled across these groups, they'll discover an interesting fact. People in first and second place tend to use the same stuff within their respective disciplines assembled the same way. There isn't any significant difference.

    Folks at the other end of the list have a wide range of components and assembly techniques whose results cover the whole spectrum. The number of "favorite" component and assembly lists is huge.

    Keep this in mind when comparing handloading components/techniques A to B to C to..... Not only does it apply to how far bullets should be off the rifling before firing but everything else, too. How a "test" is conducted will greately effect the results. Test methods that produce the smallest groups typically use the best components assembled the best way.