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Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: February/18/2013 at 16:04
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i've loaded some '06 in the past.. but I'm still pretty new to this game.  First question.. when you first start to develop a load... how many rounds do you make at each initial grain increment?  For instance if my max load is 36.0 grains of Varget... I should start out at 32.4.  how many do you make...5?   for a 5 shoot group..  3? 

2nd question... when do you stop?  when you reach max... when you start to see excessive pressure or when you gun likes a load?

Mine main goal is to find a good load and then duplicate that so I don't have to always sight-in a new batch so-to-speak.
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If I were in your shoes, knowing my book max is 36 g, I would load 4 rounds each in 34, 34.5, 35, 35.5, then 36g.  Obviously checking pressure signs along the way.  If I see no pressure signs at a book max load, I'll go ahead and load another 4 @ +.5 gr and check pressure again.  Reloading books are valuable for sure, but often feature watered down loads compared to the loads from a few years ago.  Often times rifles reach max accuracy at higher pressures.  Safe pressures that is, not some wildazzz overmax load.  You need to shoot each group through a chrono.  I like 4 shot groups because I don't know how many times when developing a load I'd have 2 touching and 1 an inch away using a 3 shot group.  With a 4 shot group you'll eventually have 3 tight ones at least out of the 4.  When I find a load that is safe, and I like the looks of, I'll then load several 5 shot groups to verify the results of my load development group.  I also like to seat the bullet out to within .005 of the lands.  When I get the right powder charge/bullet weight comob, I seldom have to monkey with seating depth.  I've always found a sub  MOA hunting load doing this.  Others may do something different but this is the way I do it.   
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: February/18/2013 at 16:38
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how do you figure out what length gives you .005 off the lands..   a special tool?
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: February/18/2013 at 17:08
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  First off you say "My main goal is to find a good load and then duplicate that so I don't have to always sight-in a new batch so-to-speak."  Anytime you change a component from the originals used in the development of that load you should back off the load (I do 3grs) and retest it.  In fact I have to do that this summer for two loads.
 
 As far as developing a load goes there are MANY WAYS to skin a cat and as long as you keep safety in mind first,whatever works for you. First off I only use reloading manuals that display the data that was deveoped using SAAMI minimum spec bbls and chambers (right now 2 Noslers and an old Hornady). I also only develop loads in the summer. I'm looking for accuracy AND performance but I start out looking for velocity potential first.  I fire a single round through my chrono starting of course with a starting load and so on (watching for pressure signs and odd chrono readings). When I approach the max velocity shown in that manual regardless of what the load data shows (so SOMETIMES I'm over their max charge a bit) I'll go to three rounds across the chrono.  When I reach the max velocity of the manual I stop.  If a pressure sign shows first,which isn't usual,I back off one grain in a large capacity case and 1/2 grain in a small capacity case. I then fire five rounds of that load across the chrono at my 100yd target to get an idea of accuracy and to make sure my averaged velocity doesn't exceed the max in the manual.        
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: February/18/2013 at 17:20
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Originally posted by Tip69 Tip69 wrote:

how do you figure out what length gives you .005 off the lands..   a special tool?
 
Get yourself a good caliper and a Sharpie marker. Take a once fired case and size a small portion of the neck (just enough to hold the bullet firmly). Now seat the bullet you intend to use out long. Assuming you are using a bolt action gun, place the round in the chamber and slowly close the bolt causing the bullet to move back into the case. Remove dummy round and measure. The sharpie is used to blacken the bullet tip so that you can see where the lands made contact with the bullet. If you don't see these marks, you didn't seat the bullet out far enough.
 
Here's some pics..
 
Coat bullet with marker. Second pic shows land engraving marks. I jacked these pics from another forum.
 


Edited by Roy Finn - February/18/2013 at 17:38
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: February/18/2013 at 17:24
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Tip, Hornady makes an overall length gauge and caliber specific modified case.  Set you back about $20 total.  You really need to know where the lands (rifling) start for your rifle to get the most out of it.  RD's method works well too. 

300S&W, not arguing, just wondering....why do you stop at the manual's max velocity if you haven't seen any pressure signs?  
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: February/18/2013 at 17:36
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Originally posted by JGRaider JGRaider wrote:

300S&W, not arguing, just wondering....why do you stop at the manual's max velocity if you haven't seen any pressure signs?  
 
Just my opinion, but I would do the same. If you are getting over book velocities with the same or less barrel length, you are most likely over SAMMI pressures.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: February/18/2013 at 17:39
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"300S&W, not arguing, just wondering....why do you stop at the manual's max velocity if you haven't seen any pressure signs?"
 
  JG,I was just heading out the door so don't think I'm being abrupt.  Big Grin  I stop at that velocity because it was developed in a chamber/bbl of minimum SAAMI specs reaching max SAAMI pressure specs for the specific cartridge.
 
  Might be back later.   
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: February/18/2013 at 18:58
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Start 3-4 grain charge weight below max shown in your manual. Use a chronograph. If the velocity you're getting is greater than the "book" velocity for a given powder charge weight, your rifle system operates at higher pressure than the test barrel used for establishing the load data (due to tighter chamber, throat, and/or bore dimensions). Therefore, you probably shouldn't load to "book max" at the bullet seating depth you're using. Start out load development OAL with bullet just touching or a few thou off lands and work up charge to max pressure from there. Once you establish max safe operating pressures, you can then test incrementally greater bullet seating depths in small increments at the same powder chg weight if you so choose to see if you get better grouping precision, since pressure decreases the further the bullet is away from the lands. However, I've never found my groups improved by seating any bullets further than about .020" off the lands. As long as magazine box length allows, I usually seat bullets to either just touching to maybe .01" off the lands max, depending on what my rifle tells me. It's all a tuning thing.

Incidentally, I measure OAL of my loads using the Sinclair ogive comparator rather than measuring OAL to the bullet nose. There's much less variation in ogive dimensions from bullet to bullet than bullet length measured to the nose. Keep in mind your seating die contacts the bullet ogive rather than the tip, and exposed lead tip bullets and meplats aren't very consistent in length, whereas the ogive is formed by swaging dies during manufacture. Measuring over the ogive when setting up your seating die will result in more consistent lot to lot OAL.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: February/18/2013 at 19:37
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Originally posted by Roy Finn Roy Finn wrote:

Originally posted by JGRaider JGRaider wrote:

300S&W, not arguing, just wondering....why do you stop at the manual's max velocity if you haven't seen any pressure signs?  
 
Just my opinion, but I would do the same. If you are getting over book velocities with the same or less barrel length, you are most likely over SAMMI pressures.


I can understand that.  What I don't understand is that quite a few years ago, 69,000 was considered max presssure in the 7mag, and today it's 59,000.  I know as long as I watch for pressure signs, many of my loads are safely over max book, over book velocity, and over 59,000.  I've got as many as 9 reloads of WW brass.  No big deal I was just curious.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: February/18/2013 at 20:15
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Whatever you do the magic word(s) is "dummy round", like no powder or primer. Get a loaded round stuck in the chamber is a real problem as primers can go off when subjected to shock like pounding the stuck round out with a rod.
 
My general approach is to find out from observation what works for other shooters who consistently post good scores or get good results but now with various component shortages some innovation is needed.
 
Sounds like you are working on something like a .22-.250 with 10% less than a 36 grain maximum Varget load. I like that combination and starting 10% under at 32.4 is very prudent
 
In general tangent ogive bullets are less critical as to seating depth than secant ogive - VLD bullets.
 
My thoughts would be to use a commonly popular combination and  start with 7-10 % less powder than what is in the manual (assuming the manual has loads intended for that type rifle as opposed to a 100 year old miltary rifle), seat the bullet so the dummy rounds function in the magazine, should you want to hunt with a repeater, then decide if you want to exceed magazine length (single load) and the arbitrary published COAL then seat the bullet closer to the leade (rifling). Pressures will increase should the bullet be pushed (jambed) into the rifling and bullet ogive contact can be determined using the felt tip ink pen or other means.
 
The general thinking is that slightly jambing (touching) the bullet into the rifling promotes more uniform starting pressures thus constant velocities. Sometimes when I load ammo that has to fit into the magazine, like the .204 Ruger, I put a slight crimp on the bullet. Some folks support this view like Lee Precision.
 
Stop way before primers drop into primers pockets with no force, ejector marks appear on the brass, case heads expand and the bolt gets sort of stuck - the load is too hot. 100 fps or so more velocity is not worth it. Some combinations yield high but within range pressures with average velocites but have good accuracy. Various manuals post different max charges with the generally the same components so common sense is important. A micrometer is handy to measure case head expansion but primer pocket tightness or lack of is another indicator.
 
I have found that most rifles seem to shoot better with close to max loads (sweet spot) with bullets seated close to the rifling - just don't skip the preliminaries. Keep good records like rounds fired and your dummy rounds marked with dates. As things wear the rifling will advance down the bore and bullets will need to be seated further out.
 
 
 
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geez... what did I get myself into now!Whacko

as I stated in initial post.. i have loaded up some 30-06.  I did not use a chrony but I did stop couple of grains less than max... seemed to work ok.

Now I'm looking at load for a .260 deer hunting round (140 gr ie Nosler Bal Tip/Hornady SST) and also a .308 long range coyote round (Sierra 165 HPBT Gameking).

Don't mind spending $20.00 for a guage or whatever.  I do have calipers... but might need a better (more precise) one.  I do have a chrony, just haven't used it yet.

Obviously, the 308 will need to be more accurate.  we shoot coyotes while hunting with hounds and almost always, the yote is running.. and for those close shoots (300 yds and less) we use a .204.  That super fast round leave less guessing with lead.  Anything over 300 is where the 308 comes in and these yotes usually are NOT running.
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Originally posted by JGRaider JGRaider wrote:

Originally posted by Roy Finn Roy Finn wrote:

Originally posted by JGRaider JGRaider wrote:

300S&W, not arguing, just wondering....why do you stop at the manual's max velocity if you haven't seen any pressure signs?  
 
Just my opinion, but I would do the same. If you are getting over book velocities with the same or less barrel length, you are most likely over SAMMI pressures.


I can understand that.  What I don't understand is that quite a few years ago, 69,000 was considered max presssure in the 7mag, and today it's 59,000.  I know as long as I watch for pressure signs, many of my loads are safely over max book, over book velocity, and over 59,000.  I've got as many as 9 reloads of WW brass.  No big deal I was just curious.
 
 
 I've always thought of long brass life ,especially primer pockets staying tight, as being a good sign of a load not being too hot.  I don't know what your over book velocities are but I'm guessing not by all that much?
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one of the reason's I started to get set up loading is I hated to have to re-sight in my rifle every time i bought a new box of ammo.... specially if a different lot than the previous box.  Seemed like a wasted a lot of rounds($$) every year doing this.  Some times it took more rounds to sight in than others.  Not sure loading your own is actually cheaper per round or not.... but overall, hope to save some.

with the 30-06 rounds I did.. I used new brass only.. didn't mess with re-sizing.  going forward, I will learn how to do that and use fired brass.  I know I have a lot to learn.

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  It's not rocket science,tip. You should start using that Chrony though.  As for measuring cartridge oal/bullet depth I used one of these for yrs before passing it on to trigger29.
 
 I don't know the quality of your calipers of course but you don't need the best out there.
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 Oh it's cheaper to reload than buying factory ammo.  One big advantage to reloading is that you control the consistancy of the cartridges.  Also by not resizing your .30-06 brass your missing the advantage of being able to "custom fit" them to the chamber of THAT PARTICULAR rifle.
Post Options Post Options   Thanks (0) Thanks(0)     Back to Top Direct Link To This Post Posted: February/18/2013 at 23:22
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Originally posted by 300S&W 300S&W wrote:

Originally posted by JGRaider JGRaider wrote:

Originally posted by Roy Finn Roy Finn wrote:

Originally posted by JGRaider JGRaider wrote:

300S&W, not arguing, just wondering....why do you stop at the manual's max velocity if you haven't seen any pressure signs?  
 
Just my opinion, but I would do the same. If you are getting over book velocities with the same or less barrel length, you are most likely over SAMMI pressures.


I can understand that.  What I don't understand is that quite a few years ago, 69,000 was considered max presssure in the 7mag, and today it's 59,000.  I know as long as I watch for pressure signs, many of my loads are safely over max book, over book velocity, and over 59,000.  I've got as many as 9 reloads of WW brass.  No big deal I was just curious.
 
 
 I've always thought of long brass life ,especially primer pockets staying tight, as being a good sign of a load not being too hot.  I don't know what your over book velocities are but I'm guessing not by all that much?
 
I guess what my point was that absent pressure testing equipment, we are pretty much guessing what is safe and no longer safe once we are over what loading manuals are saying is a "safe" load. I've had primer pockets loosen up after a few loads with some brass and not loosen when using different brass with identical powder/primer/bullet recipes. Flattened primers don't tell me a whole lot either as I've seen these "signs" as well even when using "safe" loads. So for me, and again this is just my opinion, I'll place more trust in chrono readings based on what a reloading manual states are max velocities(aka pressure) for a given load knowing these were developed in a lab utilizing state of the art pressure testing equipment. I'll let my chrono be my pressure gauge.
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Originally posted by 300S&W 300S&W wrote:

  As for measuring cartridge oal/bullet depth I used one of these for yrs before passing it on to trigger29.
 


Yep, that's the comparator I referred to in my post. Works well.
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Originally posted by Roy Finn Roy Finn wrote:

...I'll place more trust in chrono readings based on what a reloading manual states are max velocities(aka pressure) for a given load knowing these were developed in a lab utilizing state of the art pressure testing equipment. I'll let my chrono be my pressure gauge.


Amen, brotha!
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Originally posted by Tip69 Tip69 wrote:

geez... what did I get myself into now!Whacko

as I stated in initial post.. i have loaded up some 30-06.  I did not use a chrony but I did stop couple of grains less than max... seemed to work ok.

You may discover that your most accurate loads are often found several grains less than max. Don't you just love a .30-06? I have several and always think I need more.
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I can't imagine a scenario where I don't have at least 1 30-06!   Have two now... both Brownings... BAR & A-Bolt
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It has been my experience that there are at least two different nodes (powder weights) that will produce the best groups for that rifle, bullet, weight and powder type combination.  The 1st node is usually a fairly light load with mild recoil and the second is usually very close to the Max load rating.  This one has the better tradjectory but also the hardest kick naturally.

 
Usually I'm a 'bigger/hotter is better' type personality but for some reason I usually select the lighter node to load to as long as the accuracy is good.  I'm quite happy getting a couple of extra loads per pound of powder, the reduced wear and tear on me and my equipment are also a nice benefit.  Sometimes I surprise myself... Cool
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Originally posted by 300S&W 300S&W wrote:

 
  It's not rocket science,tip. You should start using that Chrony though.  As for measuring cartridge oal/bullet depth I used one of these for yrs before passing it on to trigger29.
 
 I don't know the quality of your calipers of course but you don't need the best out there.
Yup. Works great! Just used it to load some .223. Thanks again Earl! I'd never be where I am today in my loading if it weren't for you.
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  GLAD to have helped,Jason!
 
   Another "Amen,brotha!" to using a chrono as a pressure gauge.  I've been using mine as such since the late 80's.
 
  Here is some chrono data I got when developing a .257 Roberts load for a friend yrs back.  I was using 100gr bullets and IMR4895.  Data came from 3 manuals.  Load data ranged from a low of 33gr to a max of 40.8gr.
 
33 @ 2603
35 @ 2652
37 @ 2877
38 @ 2962
38.5 @ 2927
39 @ 2927
40 @ 2977
40.5 @ 3008
 
Normally because of a velocity drop I would have stopped at 38.5gr and tested 38gr multiple times but since it wasn't my rifle......................just kidding.  But even if I wouldn't have had a velocity drop at 38.5 and 39 there only being an increase of 15fps from 38 to 40 would have stopped me (deminishing returns).  I had someone run my load data through a program ("load" something?) and it showed my 38gr load as being optimum with 38.5,39,40 indicating caution and 40.5 being over the top.
 
To give you an idea of where you may be operating at pressure wise when you start having high pressure signs from the brass or rifle I had none.
 
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300, you're right, my overbook loads are what I'd call slightly overbook.  The point I was trying to make with the book max scenario is that, if you were to take  a reloading manual from 15-20 years ago, concentrating on a 160 partition for a 7mag for example, you would probably see higher velocities and higher pressures listed in the book than  you would nowadays.  Bullets, powders, rifles, and barrels are all much better today as a rule. 

I rely on a chrono too, which is why I mentioned it in my first post on the subject.
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