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WHY is my first shot high?

Discussion in 'Handloading and Reloading' started by docsleepy, Apr 7, 2013.

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  1. docsleepy

    docsleepy Member

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    The NEW SHILEN barrel arrived EARLY! Wasn't expected it until next week.

    Just ordered a precision barrel nut to go with it. That will be coming priority mail. Perhaps over the weekend....

    It is a BULL barrel, 22" (same as my sporter was), 11 deg target crown. Heavy as lead! 1:9 twist, rifling looks gorgeous.

    Can't wait to get this headspaced and the leade measured / lands and give it a whirl!
     
  2. docsleepy

    docsleepy Member

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    New Barrel

    The new barrel is installed. Before I installed it, I re-measured the headspacing of the old barrel and found it easily closed on a go-gauge, and met resistance at the top of the throw if a piece of cellophane tape were added to rear of the go gauge. I installed the new barrel to be as close to the same as possible.

    Headspaced so that it closes on a go gauge, meets resistance at top of bolt throw if a piece of cellophane tape (.003) is added to the rear of the go gauge.

    Locktited the action screws, firmly tightened (still don't have a FAT).

    Verified that the entire barrel is free floated.

    Made some measurements with a resized loaded round that suggested the placement of the datum line on the new barrel is within a few thousandths of where it was on the old barrel. In other words, I verified that the bolt would snuggle up to the barrel just about exactly the same as before (chamber appears cut correctly).

    Also I compared my sized brass to the Wilson headspace gauge and they fit perfectly in the gauge. The Wilson gauge includes a groove or slot which establishes the minimum case (head to datum) length, and the end of the headspacer gauge establishes the maximum head-to-datum length. There appears to be .006 difference. A randomly selected full sized round was at the minimum distance. The go-gauge was .002" longer. This suggests my brass are perhaps .003-.004" shorter than the (new) headspace available with the newly placed barrel.

    I hve to do a case at the hospital at 2AM so this is all for the day and perhaps I'll get to try the barrel either Sunday afternoon or Monday, which is a holiday here.
     

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  3. Andrew Leigh

    Andrew Leigh Member

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    Looking good Doc, now with the bull barrel we do not want to see groups but one hole :).
     
  4. BluegrassDan

    BluegrassDan Member

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    Let's see how it shoots!
     
  5. docsleepy

    docsleepy Member

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    OK, here is the OCW test, first go at it, on the new barrel.

    1. Measurements indicated that I might have headspaced the new barrel .001 or so shorter than the last one. As a result, I turned my FL sizing down slightly more into the press to be certain that the brass goes into the chamber without probloems. My rough sighiting in done with brass from last barrel indicated once again that "tight" cases shot low. I have no idea why, now. I now have a Wilson case-headspace tool (sort of a "chamber") and measurements on it from fired cases from the rough sightin allowed me to set the FL sizer to make NEW Hornady .308 match cases' shoulders become just .001 or .002 shorter than fired cases.

    2. Hornady OAL measurement indicated the max COAL with 120 grain Sierra spire points is a bit longer than my previous barrel, at 2.880" I temporarily had misplaced the Hornady bullet comparator tool so wasn't able to measure that and had to work with COALs. The COAL to lands with the same bullet in the cheap sporter barrel was about 2.772, over a tenth of an inch shorter.....

    3. This longer throat made it much more difficult to load "into the lands" so I decided to load to .040" shorter than the lands, which still had me putting the bullets less than a diameter worth into the necks..... I settled on 2.840" COAL.

    4. The new barrel is a 9" twist, 22" long, bull barrel.

    5. I took NEW Hornady match .308 cases, lubed, FLsized, then beveled (chamfered), then smoothed with steel wool, then Neck Sized (collet sizer -- this reduces and equalizes the neck tension on all cases; you can tell it is reducing neck tension because the mandrel takes a bit of a push to insert into the freshly FL sized cases), then charged with a RCBS Chargemaster, then bullets seated to 2.842 +/- .002". I have found that you get better results from my Lee seater if you seat, and then re-push the seater. Still, I checked every case and a couple needed a third push.

    Charges used were 40.4 (used for sighting and then in the mix also), 40.8, 41.2, 41.6, 42.0 and 42.4 It turned out that I should have made up higher charges.....oh, well, for another day.

    The rifle had been cleaned and oiled after the rough sighting in (about 25 shots as a break-in) and I did NOTHING to it prior to shooting. Temperatures ambient 82-85 degrees, I'm shooting from a shaded benchrest.

    As usual, all the charges were shot "round-robin" instead of shooting one powder group, then the next etc. About a minute or two between shots, and about 5 minutes to cool between each round. Front rest is RCBS "rock" and rear is a leather bunny. Firm hold applied to gun. Wooden shim around skinny forearm, so it rides well in the RCBS front rest. 16X scope, parallax adjusted out, rifle is easily held within 1/4" of center.

    All the "bullseye" circles are 1" diameter. There is also a 1" bar shown in each photo to make it obvious.

    RESULTS:
    1. The velocities for each shot are marked beside the imprint. There is more dispersion than I had when I annealed my cases, but they were also loaded right next to the lands, and that might have had an impact.
    2. First shot was distressingly high, second was lower and then I started the groups. I ignored that for now.
    3. The velocities observed are now slighltly LOWER than the Sierra predictions--which makes sense since I have a longer COAL, and a shorter barrel. All my velociites are within safe pressure ranges if their book is correct. I had zero cases difficult to insert, and zero cases difficult to remove.
    4. The groups started large and progressively got smaller;p the 42.4 3-shot group is a 45 degree string, all touching; there are three shots; the pink geometric mean marker is covering the center shot.
    5. The vertical placement moves slowly up and right, and then jumps up almost an inch with the 41.6 group (velocity about 2820 fps), then inexplicably moves down 1/2 an inch with the 42.0 grain group, belocity about 2875, and then back up to almost the same height as the 41.6 grain group, with the final 42.4 grain group, velocity about 2880.
    6. In the confusing final figure, I plotted the geometric centers with "error bars" that are the size of the group extreme spread. Sorry this is excessively confusing.

    Looks like it would be good to re-do the top end and extend to 42.8 and 43.2 grains. For another day. Nice group at 42.4!!
     

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  6. docsleepy

    docsleepy Member

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    I didn't photograph the first / second shots, but I did record their velocities:

    40.4 grains, cold shot, 2935 fps (WAY faster than the 40.4 group average!!)
    40.4 grains, 2nd shot, 2809 fps (still faster than the 40.4 group average)

    AFter these two shots, I re-adjusted the vertical on the scope to bring the shots 2" lower, turns out I should hve only gone down 1". Should have taken them a bit left, also from the looks of the targets. Oh well. Got it done.

    Also picked up another family that probably wants to learn how to reload while I was there today and explained the OCW process to another curious group. I make quite a spectacle with the chrony, notebook, and all the paraphenalia.
     
  7. docsleepy

    docsleepy Member

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    Old Barrel was a Homemade Sleeve

    OK, now that I have a "proper" commercial bull barrel on my Savage action, I feel more comfortable about confessing exactly what the "old barrel" was. A photo is attached.

    This was an $85 factory sporter 7mm08 barrel that shot fair to poor. I could NOT get it to shoot well enough to make me happy, so I decided to replace it. What to do with the throw-away barrel? No one else would want it, knowing that I had discarded it.... I remembered that some benchrest rifles are made by "sleeving" a Remington 700 action (to make it more STIFF) and I wondered if anyone does that to barrels.

    According to an essay on the Lilja (barrel-maker) web site, the stiffness (and thus accuracy) of a barrel increases by the 4th power of the diameter, and decreases by the third power of the length. Short, fat, best accuracy.

    Sure enough, there is a company that does just that! http://www.gunsamerica.com/blog/extreme-accuracy-makeover-the-teludyne-tti-tech-straightjacket/ For some few hundreds of $$, I could have a barrel sleeved.... But I of course wasn't going to do that to my throw-away barrel, so I decided to try a "homemade" sleeve..... 3/4" galvanized steel waterpipe, Home Depot, cut to length, inserted until it stops on the slope of the sporter barrel, then very very carefully "poured" warmed JBWeld into the gap a bit at a time and tried hard to avoid any "voids". I have not xrayed it, so I don't know how bad the remaining voids are, but I got it reasonably centered with matchsticks.

    It then proceeded to shoot noticeably better groups! Of course, nothing changed about the location of the "lands" or the chamber dimensions. The "first shot" error became PAINFULLY OBVIOUS now that the gun could easily pull off pretty reasonable groups time after time. That is what led to this thread -- I had a barrel that could shoot reasonable groups, but would NOT put the "first shot" near that group, and hence was still a big problem for hunting.... thus my request for advice, that led to all these posts......

    So now, we'll soon see if the Shilen commercial barrel, tuned up via the OCW process, can conquer the first shot problem!
     

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  8. ngnrd

    ngnrd Member

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    Isn't that what started this thread to begin with?
     
  9. docsleepy

    docsleepy Member

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    ngnrd -- yes! That's exactly why it was "distressing"

    The odd thing is that with this barrel (and n=1 tests) the velocity was HIGH rather than low (as with the previous barrel). Note that I had CLEANED the barrel and OILED it after the previous session. Perhaps the oil lubed it well enough to reduce friction enough to increase the velocity significantly. It never did that with the cheap barrel!


    I did nothing to the barrel after today's session, stored it dirty. Next time I'm out, I'll simply shoot it, expecting the increased friction to SLOW the velocity. It will be interesting to see where that shot goes, and what the velocity is.

    If that doesn't work, then I'll try cleaning it but finishing with several dry patches (leaving no lubrication).

    And if THAT doesn't work, then its time to try the grease idea again.

    I'll load the cold shots with the optimum charge weight determined by today's tests. Hopefullly, one or the other treatments will work and solve my problem!

    If not, then I'll turn again to the great folks on this board for more ideas.....
     
  10. ngnrd

    ngnrd Member

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    Before I got back to working up handloads, I'd shoot some factory ammo through it to see if the barrel swap cured the "first shot high" situation.
     
  11. ironworkerwill

    ironworkerwill Member

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    Ok, did you true up the action face and recoil lug? The action may not be out by much but the recoil lug (FACTORY) will be several thou smaller at the top compaired to the bottom.

    looks nice btw
     
  12. docsleepy

    docsleepy Member

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    Probably a good idea to go get some factory.

    Did not true the action. Am using a precision ground Recoil lug and nut. The recoil lug was a precision ground even with the last barrel.
     
  13. Andrew Leigh

    Andrew Leigh Member

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    Just some total fliers here Doc.

    Before you take your first shot is your barrel dry. I oil my barrel after cleaning, for storage that is, and then run two tight patches through to remove all the oil before firing and I stay on the money. Is the chamber also dry?

    If you are still high with two barrels then how can it be the barrels, especially given that the new barrel is also heavier and more stable?

    Do you hold the forearm down when benching?

    Is it possible that the bag in your front rest is incorrecly packed and that with successive shots that the media in the bag settles and starts to give good results?
     
  14. BluegrassDan

    BluegrassDan Member

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    I think Andrew Leigh could be correct. There's something inconsistant with that first shot, and it could be related to the position in the rest. The idea of the bag settling makes good sense. Does the gun return to the exact same position in the rests from shot to shot?

    What kind of wooden shim are you putting between the forearm and bag? Seems unnecessary and potentially harmful to accuracy.

    Not to be redundant, or to repeat myself, OR keep saying the same thing over and over, but you need to consider getting a dang torque wrench. As anal as you're being about these minute details, your gun could benefit by equal tension on the action screws. And Loc Tite is not necessary on your action screws if you have around 60 inch pounds of pressure on them.

    Glad to see the smaller groups.
     
    Last edited: May 29, 2013
  15. docsleepy

    docsleepy Member

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    You guys are killing me with great ideas!

    Okay, so I ordered the F a T wrench from Midway. It will be here soon.

    The barrel should not have been wet, it was
    Patched with a small amount of oil after the last session, and the rifle in controlled conditions in between. I do think I forgot to swab the chamber, but I did it later and didn't pick up anything.

    Frankly, I don't make much of one test, and this is still a very new barrel with less than 45shots through it.

    I don't think the front rest packs any at all. The bottom portion of the rest is pretty uniformly packed. This is a hunting rifle, remember? It has swivels on the bottom of the firearm. The wood shim is made of one by fours, in a U-shape, with holes for the swivels. Allows it to fit the front rest. Dramatically reduces cant.

    I can't swear that this rifle returns to the exact same position. The rear bag tends to move with each shot. It is possible that I am not starting with the same position in the rear bunny ears. I will take pains to bang the butt down in the bunny ears the next time, Before the first shot.

    My hold on hunting rifles for benchrest is a firm grasp on the rifle, I'm pulling it back into the shoulder pocket with about 5 pounds of pressure. I don't make a specific effort to hold the forearm down, more back. The forearm does not really jump. With my extremely heavy six PPC rifle, you can completely let go of the rifle, and touch the trigger, and the rifle will move 2 inches back and stop. Not so this lightweight 7 mm08.

    For the next cold shot, I want to try doing nothing to the barrel. Then the following time I will try your suggestion of dry patches after previous cleaning well.

    Great ideas, guys! Looks to me like 42.4 or so is going to be the accuracy node. I will try another test around that region.
     
    Last edited: May 29, 2013
  16. docsleepy

    docsleepy Member

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    Cold shot left barrel alone

    OK, so here is the data from the "foulers" this morning 85 deg F.

    It was a bright sunny day, so my chronometer never picked up any shot except one time.

    Loading: 42.4 grains, the optimum from the previous outing, brass was some of that used in the previous outing, never annealed, new Hornady 308 match brass, necked down to 7mm08 in FL die.

    FL sized, neck sized (noted normal pop inserting the mandrel in the neck, felt like normal to slightly high neck tension), charged on Chargemaster, loaded to same length as last time. I loaded seven rounds this same way as foulers/cold shot tests.

    Note that I adjusted the windage of the scope to move the POI 4 clicks (1" at 100 yards) to the LEFT. This was because the 42.4 grain load previously shot 1" to the right. No other adjustments.

    Tested the fore n aft movement of rifle in bag/front rest, and made SURE to push the butt down into the "ears" of the rear leather rest.

    Did absolutely nothing to the barrel except ran a dry patch into the chamber only. It was not cleaned or lubed at the conclusion of the previous session.

    As always, the diameter of the circle is 1"

    RESULTS:
    1. The first three shots are a cloverleaf!! Just about 1/4" higher than predicted by the previous session's results. This is VERY GOOD! I dunno why the 4 clicks ended up with the shots 1/4" too far to the left, but that is no big deal.
    2. I next shot the OCW "round robin" tests (see next post). As the barrel was becoming progressively warmer, I shot the shot labeled "warm" which is slightly more leftward and sligtly lower. Near the end of the entire session, I shot the "hot" shot, which was considerably lower.

    CONCLUSION:
    There is no discernible error in the "cold shot" in this day's tests. Only when the barrel has run >15 shots through it does the point of impact begin to shift. This result is very acceptable for hunting, since I've never shot more than 2 shots. Can't say for sure if it is the rear bag banging, or the lack of cleaning, but whatever, it worked at least today.

    WOW! Big improvement! Hope it is repeatable!
     

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  17. docsleepy

    docsleepy Member

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    Higher charge weight OCW

    OK, here are the result of testing somewhat higher charge weights.

    Look a bit carefully at the photo -- the bullets are landing low and left of the aim point, so you may be confused. On the top row are charges 42.0, 42.4 , 42.8; on the bottom row is the 43.2 and the bottom right group shows the geometric centers of each of the groups (they are clustered very closely together) and the center of the foulers (which is higher, see below for the differences).

    CASE PREP
    I decided to test my annealing as well while doing this. Absolutely new Hornady .308 match cases were lubed, sized down to 7mm08 in a Lee FL sizing die, outside lube wiped off, and then annealed via my standard procedure described in posts above, dried in 200 degree heat for 20 minutes (and left alone for an hour while I did other things). They were then inside neck lubed and Lee Collet neck sized and primed, then charged using RCBS chargemaster at the various weights, and bullets seated to the same length as the previous session. All lengths were checked within .003" and fixed if necessary.

    Things noted:
    1. It was very obvious that the neck tension developed by the FL sizer was not as high; the mandrel of the Lee collet went into the cases with notably less effort (still some, but less) than I'm used to with cases that have been used several times. This was quite curious to me. I take it to mean that the brass was indeed softer, and actually softer than I'm used to with multiply sized / annealed cases. Normally when you collet neck size these cases, you have the distinct feeling of the mandrel forcing itself into the FL-sized neck (Lee must set their collet mandrel slightly greater diameter than their expander ball in the FL die....) and also when you withdraw the case from the die, there is a distinct pop (like children make with their finger popping out of their cheek/mouth) due to the suction developed as the tight neck comes down the mandrel. I didn't get as much of that "suction sound" as I'm used to.

    So my take on this was that these necks (annealed when not hardened except by the FL neck sizing reduction from perhaps .306 to .282 or so) were SOFTER than my usual experience.

    2. When I inserted the bullets, it was also plainly evident by feel that they slid in with much less force than I'm used to -- the foulers went in with a notable initial resistance as the bullet forced its way into the neck.

    So I concluded that I had a set of brass with an unusually soft set of necks --even for me. How would they shoot?

    RESULTS:

    1. Again the groups at 42.0 and 42.4 are the best -- but they are not as good as the un-annealed brass results of the previous session, and clearly not as good even as the three "cold-shot-foulers" !
    2. The VERTICAL movement of the groups -- the primary purpose of all this optimal charge weight testing -- demonstrated that all these charge weights today are virtually identical. The geometric means moves almost none at all,while the group size blows up above 42.4 grains.
    3. The last (hottest barrel) shot at the highest powder level is actually higher than expected. I think the group is just widening, but this was interesting.

    CONCLUSIONS:
    1. 42.4 (at 85 degrees F) seems to be the optimal charge; at this point the vertical position is fairly fixed, and the group size is minimized.
    2. I was NOT able to get any velocities due to lack of clouds, so can't measure velocity standard deviations.
    3. This neck tension seems BELOW the optimal range -- too soft brass. Andrew and the others will be glad to see this proof! Apparently the working of the brass with initial necking down is not that much, and it would be better to go a few shots/reloadings before any annealing (I know they will agree). The overly soft necks seem to have resulted in larger groups. And a lower, and leftward point of impact. The POI change could be adjusted for, but the group size is suboptimal. There was a note in the "warehouse studies" article posted above that they noted that any bullets that seated with a required force below a certain point, shot poorly. Seems the same here.

    So I may run these brass up and down in the FL die a few times to harden their necks some and compare again??
     

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  18. BluegrassDan

    BluegrassDan Member

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    I think you've figured it out. The POI on lighter weight hunting rifles can shift depending on how the gun is held and/or cradled in the rests. Perhaps your first shots have been high (until now) because the gun was not seated as firmly in the bags as after a few shots.

    This is also why the POI of your cloverleaf was 1/4" off from the previous shooting session. You can't duplicate the environment from day to day, and you can only try your best to seat the rifle in the rest, weld your cheek, control your hand positions, and breathe consistently.

    I'd quit screwing with annealing the brass. It's overkill, and you're less likely to be consistent. If your best groups were from a cold bore with un-annealled Hornady brass, then use that for a while and see how consistant you can be.

    As folks have said before, you've got to "let it ride" for a while. Stick with one thing and practice consistency.

    Here's what I suggest. Prep 25 cases of un-annealled Hornady (fire formed and neck sized only WITHOUT lube on the neck - which can create inconsistant neck tension). Load up 5 rounds of 42.0, 5 of 42.1, 5 of 42.2, 5 of 42.3, and 5 of 42.4. Take a few hours at the range (no caffine beforehand), and shoot those 5 shot groups allowing the barrel to cool for 3-5 minutes between shots, and 15-20 minutes between groups. Make sure the gun is seated firmly in those bags before you start, and get rid of that dang wooden shim between your forearm and bag. That's sure to mess things up.

    Then do this ENTIRE process again to figure out which load your rifle likes best.

    Then come back and tell us which load is best. Simplify, simplify!
     
  19. docsleepy

    docsleepy Member

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    Bluegrassdan: yep, I think you are right. The rear bag may have made a bunch of difference! Pounding it in.

    But it bothers me the difference in the point of impact of the (over)annealed cases, and their increased group size. So I set about to find some way to MEASURE my neck tension/annealing:

    First, I could NOT find my spring scale so I had to take advantage of Hookes law, and make one first, and calibrate it using a 7 lb weight and assume linearity in the expansion of the automotive spring from PepBoys that I used as the scale device.

    Next, I took 2 of the non-annealed cases that shot the excellent cold bore group, and 3 of the over-annealed cases, and proceeded to measure, on a Lee press, at right angles to the arm, with the scale connected by a non-expanding string, to just near the end of the lever arm (using the ball to stop the string). The lever arm is about 18 inches. I measured the force in pounds needed to (1) insert the collet die mandrel in a freshly full-length sized case, and (2) to get the bullet seated -- it just pops in once it starts, because these are flat base bullets.

    Here are the results:
    [It is difficult to get this thing to space out columns....]
    .............................Pounds to..................Pounds to
    .............................insert mandrel.............seat bullet
    Non-annealed #1..........5#............................6#
    Non-annealed #2..........6..............................3

    Overannealed #1..........2..............................3
    Overannealed #2..........3..............................4
    Overannealed #3..........2..............................2


    Comment: the overannealed cases a much softer to admit the mandrel after full length sizing, and generally have low forces required to seat the bullet, in agreement with my intuitive sense after loading 16 of them for the last test.

    Next, I decided to find out HOW MUCH I was work-hardening the overannealed cases by repetitively full-length sizing them x 3 ( a practice y'all collectively didn't like )

    I took Overanneled Case #3 and successively FL sized it and measured the necksizing pressure, until I hit 50 FL sizings: here are the data

    Overannealed Case #3
    Number of times total FL sized.........Pounds to insert collet die mandrel
    6 total.........................................3#
    12 total.......................................3#
    25 total........................................2#
    50 total........................................still about 2#...something makes no sense!

    I concluded this wasn't going anywhere, and worked on "bullet seating" force.-- probably more important anyway!

    Final experiment:
    I took Overannealed Case #1 (which had seated with 3 lbs force) and FL sized it five times and then neck sized it ( measured 5 pounds!!!) and then seated a bullet -- SIX POUNDS. Same as Non-annealed case #1!

    My conclusion #1 is that something was screwy with my testing technique for overannealed case #3 and the mandrel, and the final test seems to say that you can overanneal a case and with roughly 5 or fewer FL sizings (which sizes the neck both down and up and thus work hardens it) you can return it to the same approximate neck tension as a case that was not annealed since the factory and loaded/shot twice.

    Conclusion #2 is that it is possible with simple equipment to measure the bullet seating force and it would probably be smart of me group cases together that have similar necksizing / bullet seating forces -- they are more likely to group siimiliarly. Any case that seats with unusually LOW pressure is likely to shoot LOW in this gun at 85deg Fahrenheit anyway....

    #3 And I hope I find my real spring scale soon.
     
  20. docsleepy

    docsleepy Member

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    It next occurred to me to wonder what would be the bullet seating force if I skipped the collet neck sizing die.

    So I repeated the test with a fresh twice-loaded/shot non-annealed new case: bullet seating force after only FL sizing approx 7.5 lbs.

    Overannealed case, shot once since annealing: bullet seating force after only FL sizing -- approx 6 lbs. Still lower than the non-annealed, but not unreasonable.

    The lee neck collet mandrel must be a bit smaller in dia. than the expander ball in their FL 7mm08 sizing die.
     
  21. docsleepy

    docsleepy Member

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    As one person requested, I purchased some commercial 120 grain 7 mm 08 ammunition.

    I think I will use a kinetic bullet puller to remove one bullet, resize, and measure the bullet insertion force on the commercial ammunition. That will give me a baseline for what hardness the commercial guys think is optimum.
     
  22. John C

    John C Member

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    As you mentioned, it sounds like you're over-annealing your brass, softening it too much.

    Here's an affordable machine that makes the guess work out of annealing: http://www.cartridgeanneal.com/

    Check it out.

    -John
     
  23. docsleepy

    docsleepy Member

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    Very impressive. I watched the video. He's using more heat than I use but way less time. Think this is worth trying.
     
  24. John C

    John C Member

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    Doc;

    That's what I suspected. There are some good articles on the technical aspects of annealing cartridge brass. Basically, there is steep arcing curve as to heat and time and what that does to the brass. Too long under the heat, or too much total heat, no good. Too little heat, for not enough time; also no good.

    A lot of bench rest shooters anneal after every firing, but they're annealing under very controlled, repeatable conditions.

    I want to say that I've enjoyed this thread immensely, along with your Mosin thread. I've enjoyed seeing you wring out your process for repeatability. I also appreciate your desire for bang for the buck, but also your willingness to spend money for results. This thread has turned out to be a great primer on how to accurize a Savage. I just bought a Savage 110 from 1989, and I'd like to follow in your footsteps.

    I think that once you sort out your annealing process, either by giving up on it or getting a repeatable process, and a getting a torque wrench, you'll be mostly there.

    Does this rifle have an accu-trigger? Whether it does or not, have you tuned the trigger down to the lowest possible weight? Even if you don't want too low of a trigger weight for hunting, while you're dialling in you rifle, you may want to lower the trigger weight, and then raise it for hunting. With an accu-trigger, the safety issues of a low trigger weight are largely obviated.

    -John
     
  25. docsleepy

    docsleepy Member

    Joined:
    Mar 10, 2009
    Messages:
    1,023
    Great comments! I ordered a bottle of the Tempilaq

    remember I had been FL sizing three times after annealing, and I guess I had blundered into a way to return to a normal hardness. We'll see. video suggested that all I was still way over annealing and if this will make it more repeatable, I'm all for it! I started annealing when I had the opposite problem, way too hard brass, and bullets would simply fall out. At that time, one annealing gave me some of the best groups I had had for a while. However, my process doesn't seem perfect, at all

    This neck tension thing seems key. I ordered a Wilson
    Inline seater, on clearance! From Midway last night. I can put it on top of a bathroom scale, and then seat by hand, or Arbor press I have an arbor press. The scale will allow me to measure seating pressures, giving me a way to sort my loaded cases.

    From the results above, the difference between normal hardness and over annealed was about an inch at 100 yards. So it should be easy to tighten the process so that I consistently achieve less than half an inch. That will be plenty adequate.

    This savage is an old one, and does not have an Accu
    trigger. I have the trigger adjusted pretty light, in the range of 2 pounds. Once the screw got loose, and it went down to 1 pound and became erratic! I drilled a small hole in the stock so I can reach the adjustment screw without having to take it apart.

    This has been great, getting all these wonderful comments and suggestions from everyone! When I have my neck seating pressure sorted out, I put some more data up.
     
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