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Old February 2, 2013, 10:16 AM   #1
alesix
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reloading 308 confused on bullets, powders and load data - help

have savage 10fcp-sr 24" 1/10 and new to reloading so confused for safety.
also have remington 700 sps 308 24" 1/10
used once fired brass and have imr 4320 and imr 4007ssc powder
bullets are hornady 168gr bthp match and hornady 150gr fmj/bt
cci 200 primers

using hornady reload manual, speer reloading manual and imr data specs for 308
hornady list imr 4320 for 168gr bullet (charge 33.9g to 42.2g) but no 4007 listed and it list neither powders for 150gr

speer lists imr 4320 for 150gr fmj/bt (charge 44g to 48g) and 168gr bthp match (charge 42g to 46g) their min is hornady's max charge load
but does not list imr 4007ssc

hodgon list 150g nos bt with imr4007ssc charge 44.7 to 48 and imr 4320 charge 44.1 to 49 but no mention of 150g fmj/bt
hodgon list 168g sie hpbt with imr4007ssc charge 43.2 to 48 and imr 4320 charge 41.5 to 46gr

and cannot seem to find a comprehensive data sheet listing all bullets (whgts and mfg) and charge loads and powders

does this even really matter?

i can use hodgon data listing both powders and both types of bullets
but are nos 150g bt the same as hornady 150g fmj/bt so do same charge or if different dimensions will get different pressures for same charge?

same problem with 168 g

just don't want to go boom in the wrong way!!!!!!!!!!!!!!!!!!

if all bullets same dimension for given gr and style then can use data from any mfg?

Last edited by alesix; February 2, 2013 at 10:52 AM.
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Old February 2, 2013, 11:28 AM   #2
KillThe9Ball
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Alesix,

I'm new to reloading myself and am worried about 'kabooms' also!

Regarding everything I've read, if the bullet type/style/weight are the same, most load data will be close and can be used.

I'm sure you're working-up so you should be fine. From what I've read, the main differences in pressure and velocity you'll find when using the same type of bullet (from different manufactures) will be:

1. Jacket Thickness
2. Jacket Alloy/hardness
3. Dimensions and length of your chamber/throat
4. Bore wear (applicable firearm)
5. Bullet neck tension/crimp if used
6. Case wall thickness (case volume) + Length
7. Primer type/brand
8. Barrel Length
9. Ambient Temperature (30C to 100C I have read can create 4-10% pressure difference depending upon powder type).

All of the variables above are what makes some load manuals hotter or lighter than others because of the difference in test equipment (and legal liability fears). From my understanding, the brand of the bullet is the least significant characteristic assuming all else is the same (for example, Two different 168 Gr. FMJ BT from different manufactures). Furthermore, from my understanding each company puts their own manual out basically for extra revenue even though it's not necessary. If Nosler can make you think you need a Nosler manual to load Nosler bullets, well, they can then sell you two products (the bullets and their book).

Also, keep in mind that a JHP and FMJ can have different bullet lengths which will result in different levels of case volume once seated - which will affect pressure.

I'm sure someone later today that has a little more experience will chime in on this subject. I'm certainly not an expert and hope you don't take anything I say seriously... If I'm wrong on something, or perhaps worded something wrong, I would hope to be corrected... Seriously!

Good Luck
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Old February 2, 2013, 11:56 AM   #3
alesix
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wow, now really confused

i started out thinking i just needed reloading press kit (got rcbs rock chucker supreme kit) dies and components

then decided to be safe got several manuals,
a digital scale (to verify and cross check loads and compare loaded cartridges for uniformity) this is in addition to balance beam scale in kit
a tumbler to clean brass and check for problems
a magnifier to help see close up for problem cases
a case trimmer to trim all cases the same
a second caliper to cross check and verify first caliper dimensions

just plinking so don't really think i need to do head space and measure seating depth off lands for each of the two rifles and because loading from magazines the 2.8 oal should be fine

now you mention all this:
1. Jacket Thickness
2. Jacket Alloy/hardness
3. Dimensions and length of your chamber/throat
4. Bore wear (applicable firearm)
5. Bullet neck tension/crimp if used
6. Case wall thickness (case volume) + Length
7. Primer type/brand
8. Barrel Length
9. Ambient Temperature (30C to 100C I have read can create 4-10% pressure difference depending upon powder type).

holy sh..., will i have to get another degree to figure all this out, and another job to pay for it all.

the videos i have watched and posts i have read all seem to show it to be a pretty simple process for target shooting or small game hunting, like varments.
not measuring case thickness everywhere, throat length, bore wear, neck tension crimp, jacket thickness, alloy of brass, temperature --- holly cow

not trying to get 1 inch groups at 12 miles, just simple targets or varments at 100 to 500 yards
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Old February 2, 2013, 12:04 PM   #4
alesix
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100c where do you shoot

when i checked temp conversion for 100C it showed it to be 212 degrees fahreniet. where do you find to go shooting at this ambiet temp?
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Old February 2, 2013, 12:06 PM   #5
KillThe9Ball
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No No No...
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Old February 2, 2013, 12:11 PM   #6
KillThe9Ball
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I was simply trying to state where all the discrepancies in load data come from, at least from my readings.

I'm still a newbie... I don't know anything....

I wasn't trying to imply that I did, I registered for this site a week ago and have an open question still regarding bullet v. load manual...

I just listed things I've read that affect pressures/velocities.
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Old February 2, 2013, 12:12 PM   #7
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and no, I didn't mean to list the average climate in hell.. lol
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Old February 2, 2013, 12:15 PM   #8
alesix
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i don't know about you but the more i read about reloading the more i get conflicting info and lots of bits and pieces

i am becoming a very confused individual
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Old February 2, 2013, 12:18 PM   #9
KillThe9Ball
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oh, never mind, I'm a little dull this morning... Didn't realize you were being facetious
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Old February 2, 2013, 12:31 PM   #10
KillThe9Ball
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My Mistake,

I thought you were being a little facetious at the moment, obviously you weren't. Still a little 'out-of-it' this morning.

I've managed to work-up a few good handgun cartridges, if you get a good 308 load I'd like to trade data with you. Deer season is 9 months away here.
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Old February 2, 2013, 12:55 PM   #11
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Just pick a data sheet that comes closest to what you are using.
Barrel length varies from data sheet
brand of primer can change the pressure
depth of bullet seated in case can change pressure
capacity of round can make a difference, some loads are compressed loads, meaning the bullet squeezes the power into the case, where some cases are only 1/3 full. Depends on type of power.
some powders burn at a faster rate than others. Makes the pressure increase at a faster rate.
Myself, I go with the load data from the powder manufacturers to stay with in the pressures recommended. That is why you see some powders are not recommended with certain bullet weights. a particular powder and bullet may cause the case pressure to increase to the point of failure .
Each individual chamber/barrel may behave different with the same load due to chamber size, distance to the beginning of the rifling, barrel length, outside air temp, barrel temp. and other "hidden variables".
These may not make it dangerous, but will greatly effect the accuracy of the projectile. the question then becomes,"how close is good enough?" Is a ragged hole 200 yard group what you want, or is 2 minute accuracy good enough, or are you just happy it goes off and you can hit a barn with it. The precision will be entirely up to you.
All of the case dimensions are important , so that you do not have a case that is over /under sized that could rupture in the chamber because of excess pressure. The more precision the case fits your gun , the more accurate the bullet will hit the target
start with a lower loading and work your way up to an accurate load,watching for signs of case failure all along the way.
you can get it so precision that the load for the first cold bore shot can be matched to a second loading to compensate for the temperature change . If that is what you are wanting to do. There are many who enjoy reloading to precision , more than shooting .
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Old February 2, 2013, 02:11 PM   #12
alesix
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going to resize each case with full length die, then fire in each rifle and keep separate so they are sized for each chamber of the two rifles then neck size after that. all case will be measured and trimmed before each reloading

would like to get decent realistic groups at 200 to 300 yards, not needing 5 through in one hole and not wanting 6" groups, then maybe later go for more precission and greater distance

just wanting to start learning and doing as a hobby, then taker it from there
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Old February 2, 2013, 02:35 PM   #13
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Since you are not reloading for gas guns (AR-10's, M1A's, etc.), you can probably adjust your resizing die by "sneaking up on" the chamber as a gauge. By that I mean, carefully adjust the FL sizing die for more sizing in 1/32 turns (0.002") until the bolt just closes without undue effort.

If you segregate brass by rifle, this should work.

An alternative is to get an inexpensive cartridge headspace gauge (such as the pattern made by LE Wilson) and use that to make sure you are between the upper and lower steps on the gauge. That would be "within SAAMI spec" and should, therefore, fit any modern rifle chambered for .308 Winchester. (Assuming it's chamber is in spec.) Then your reloads will work for either rifle.

At any rate, if you over-resize, you can set up what it called "induced excess headspace", which can lead to dangerous case head separation after just a couple of reloads.

Primers should be seated flush or slightly below flush.

Don't ignore the need to check for trim length. Repeated resizing makes the case "grow" in length. Overlength cases can be crimped by the rifling and lead to dangerous overpressure.

The load data for a given bullet weight and the recommendation to "work up" for a given rifle should be followed as final safety precautions.

IMO, the rest of the stuff (sorting cases by weight, neck turning, concentricity gauges, etc.) is benchrest territory. No harm done if you have the time, but no decrease in safety if you ignore these.
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Old February 2, 2013, 03:17 PM   #14
alesix
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going to trim to 2.007. saw 2.015 is max cartridge length and suggested 2.005, so i thought i would go over just a couple thousandths for safety precaution while well under max and keep col little shy of 2.8, maybe 2.797

does this sound safe while keeping some degree of accuracy
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Old February 2, 2013, 04:17 PM   #15
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i can use hodgon data listing both powders and both types of bullets
but are nos 150g bt the same as hornady 150g fmj/bt so do same charge or if different dimensions will get different pressures for same charge?


Pretty much. No book maker produces absolutely specific data for any specific rifle or anything else; bullet-case-primer-powder lot-which way the ducks are flying all vary a tad. All the book makers can do is tell us what they got in their test rigs using their components on that day and our's ain't exactly like theirs.

There are those few high-lighted lines found in every manual that tell us to start low and work up slowly to the book's max UNLESS you experience early signs of excess pressure; they're serious about that. Follow that one rule and you'll be fine no matter your components or the serial number of your specific Remington 700 SPS 308 24" 1/10 or Savage 10fcp-sr 24" 1/10 or anything else, but ignore that rule and no book data is totally "safe.'
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Old February 2, 2013, 09:01 PM   #16
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Quote:
going to trim to 2.007. saw 2.015 is max cartridge length and suggested 2.005, so i thought i would go over just a couple thousandths for safety precaution while well under max...
I believe there may be some over-thinking going on here...

As cases are resized, they tend to grow. (RCBS X-dies excluded...) So, you measure them and if any are over 2.015 you trim them back to 2.005. Then you don't have to trim every time the case is resized, just do a length check.

As long as the case is under maximum case length, there shouldn't be an issue. Shorter isn't safer. Shorter just reduces the amount of neck available for bullet tension.

By the way, the Wilson gauge I mentioned will measure both lengths with one "case drop". Look at one end to check cartridge headspace, then invert and stand on a flat surface and check the other end for need to trim.
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Old February 3, 2013, 09:56 AM   #17
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alesix,

I load for a 10 FP Savage and my son and two range buddies each have the newer 10 FCP-Ks. We compile all our loading data and compare it so we have some pretty good idea of what our particular rifles prefer. We tend to be meticulous in measuring both while loading and in recording results so the data we have gathered gives us a pretty good idea of the similarities and differences in each of the 4 rifles.

Two of our rifles are slightly more accurate with 150 up to 168 bullet weights and the other two seem to prefer heavier bullets up to 175 grains. They all shoot all the weights well under 1 MOA.

Every rifle is different so your probably going to find that your Savage and Remington will like different bullet weights, seating depths, and powder loads too.

All our Savage Model 10 .308s have preferences for specific seating depths because all the chambers are slightly different.

One of our 4 chambers is very short and my chamber is very long. The other two fit right in the middle.
My barrel has over 5000 rounds through it and that sometimes accounts for chamber erosion but it still shoots great.

In fact it is shooting better now that I have started measuring all loads for chamber depth instead of measuring for overall cartridge length. Turns out that there is usually more variation in the bullet tip length than there is in the die, so measuring cartridge length to the bullet ogive is more accurate than measuring the OAL when seating.

There is a very good informational article in the new Berger Reloading Manual starting on page 148 that recommends that you set the bullet seating depth based upon the specific bullet you are using and on your particular chamber depth rather than based on the initial manufacturer's general recommendation (even theirs).

All of our Savages have had really good accuracy results with H4895.
I tried Vihta Vuori N140 powder over the last 5 months and have had the best results to date, probably because it meters so well.
Two of the other shooters have also switched and have similar improvements.
All of us have found that N140 shoots slightly slower than the H4895 but the groups are tighter.
The standard deviation in velocity through my chronograph with N140 is usually under 10 fps compared to 15 to 25 fps with some of the other powders.

IMO the two biggest contributors to accuracy in a hand load are consistent neck tension and consistent powder loads that yield the most consistent velocities. After that, consistent seating depth is the next big factor.

We have not had results as good with Varget or Reloader 15.
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Old February 3, 2013, 10:18 AM   #18
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I shoot a Savage 10BA in .308 and have excellent results with Sierra 180gr in a 1-10" twist.
I just bought 500 168gr matchkings to try next.
I however use Hodgdon Varget which is very temerature stable.
Don't assume that a load you develop at -30F will be safe at 90F

You will soon begin to collect a bunch of different reloading manuals which will grow into your own data library over time.

Here is the link to Sierra's data.

http://www.6mmbr.citymaker.com/f/sierra308Win.pdf
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Old February 3, 2013, 02:08 PM   #19
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Gotta enter this thread 'cause there's a bunch of myths put in print.

First off, I think one could use a long established load that's been used to win matches and set records. With new cases and the right components put together the right way with the right tools, if one's rifle doesn't shoot under 1 MOA at 100 yards with that stuff, it ain't the ammo's fault.

Second, this old theory that a "perfect fit" of case to chamber is best for accuracy is usually championed by folks that don't understand how a rimless bottleneck case fits the chamber; both when first loaded and when fired. When fired, which is what counts, their front end's perfectly centered in the chamber up front on the shoulder and the neck, if well centered on that shoulder, will be perfectly aligned with the bore. Doesn't matter how much clearance there is around the case; the back end's pressed against the chamber opposite the extractor anyway. How else would brand spankin' new mass produced ammo fitting all sorts of chambers shoot 1/2 MOA or better at 600 yards? That's the norm with good lots of mass produced Palma ammo fired in .308 Win. match rifles.

Third, the most popular myth of neck only sizing; finally busted by benchresters. While shoulder fired match rifles have been shooting just as accurate as benchrest rifles rested on bags for decades, they've done so with full length sized cases with proper dies and techniques. Benchresters finally moved from neck sizing to full length tools and methods a few years ago. While the size of their smallest groups have remained the same, the biggest groups they shoot are a lot smaller; overall better accuracy. Of course one should always measure their accuracy by the largest groups for a given load as those are the ones that show what happens when all the variables add up in the same direction. Ever wonder why Sierra Bullets has been full length sizing their fired cases since the 1950's to test their stuff for accuracy and nobody shoots 'em as accuate as they do?

Fourth, small muzzle velocity spreads and uniform case neck tension are not nearly as important as other internal ballistic stuff. That's been proved by arsenals and others loading match ammo and the best lot has often had a greater velocity and release force than those not so accurate. Bullets being a few ten thousandths bigger than the barrel's groove diameter plus powder choice and charge producing uniform pressure curves are way up on the list. Primers uniformly igniting powder is also important; hot magnum ones are typically not as good as milder ones.

Fifth; the myth of getting exact bullet seating depth. It's amost impossible to get a constant seating depth or distance to the rifling. Bullet ogives are not all the same shape for a given lot of them as the metalurgy ain't perfectly uniform. They all have different ogive shapes a couple thousandths different from each other. Plus, rimless bottleneck cases position the bullet in the chamber relative to its distance from the case shoulder. Case headspace (head to shoulder reference point) will have a few thousandths spread so bullet distance from case/chamber shoulder, and the start of the rifling, will also have a few spreads. Even with absolute zero tolerance from case head to bullet ogive reference point. Want zero seating depth spread? Seat bullets out to jam into the rifling and seat back a few thousandths when the round's chambered. This has been popular for decades with Sierra's; not so with Berger's that need a few thousandths jump.

There several others, too. . . . .
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Old February 4, 2013, 10:14 AM   #20
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Bart,

Thanks for dispelling some of those myths.

I have a question on full sizing versus necksizing that you might be able to clear up.

The benchresters I know have spent bundles of $ trying to gain every advantage they can to get the last bit of accuracy.
The ones I know have had their full sizing dies specially made to match their individual rifle chambers. One shooter with two benchrest rifles in the same caliber has even had special dies made for each barrel. And yes he full sizes with those special dies for every reload. He wins his share of local matches so your statement on full sizing has merit.

But the kind of investments that benchresters make in special stuf is foreign to most of us. Just the bolt on one of his benchrest rifles costs more than two of my rifles. Those specially made dies for every specially-made barrel are out of my league.

I'm not sure that kind of full sizing with specially machined dies quite equates to what most of us use for sizing dies so I'm not sure that using benchresters as examples of full versus neck sizing relates to what most of us could do with factory dies that are made, as you point out, for chambers that are designed for the range of factory ammo.

Is there any data that you know of on full sizing with an off-the-shelf dies that shows full sizing is better or worse than neck sizing?

Just as an aside, I have also heard that neck sizing supposedly puts less strain on the cartridge and makes them last longer and get trimmed less. That might also be a myth that you could dispell also.
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Old February 4, 2013, 12:14 PM   #21
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Rimfire5, Sierra Bullets has been using off the shelf full length sizing dies on their fired cases testing their stuff for accuracy since the 1950's. I doubt anyone shoots their stuff any more accurate than they do. . .with any type of reloading stuff. They use standard Redding full bushing dies on cases such dies are made for, standard dies for the others. Their best match bullets shoot into 1/4 MOA at 200 yards just like the benchresters get with their custom dies. And using match barrels with standard SAAMI spec chambers (or equivalents thereof) without tight necks. RCBS also make the same type of die and are just as good.

I and others have got several dozen reloads per .308 Win. case full length sizing them every time. Just adust the die so the shoulder's set back no more than 2 thousandths and have its neck diameter about 2 thousandths smaller than a loaded round's neck. It help a little if the die doesn't size the body diameters down more than 2 to 3 thousandths, too. Benchresters like their full length sized case body diameters to go only about 1 thousandth smaller than fired ones, but I don't think that's important unless your biggest groups are no larger than 1/10th MOA at any range.
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Old February 4, 2013, 02:08 PM   #22
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Bart,

The only factory ammo with Sierra bullets that I have tested with is Federal and Black Hills. I have never seen Sierra ammo for sale in fact, I didn't know that they made any. The LEOs that come to our range to practice all use Federal Gold Match ammo that they are issued. I don't know how Sierra full case sized ammo would compare to factory ammo that I have purchased, but since factory ammo is using new cases, I would expect them to be full case sized. I have measured the factory ammo loaded with Sierra Match King bullets against hand loads of similar specs that I have reloaded using neck sizing, velocity tuning through powder measuring, and seating depth measured but COAL and via the ogive.

I shot all of these rounds using my Savage 10 FP using a bipod and rear bag off a bench at 100 yards. I've put almost 5000 rounds through that rifle and surprisingly the best group load averages today are better than when I started.
I will admit that probably means that trigger time has improved my technique more than the rifle accuracy has degraded.

Here are my results - all measured using the On Target software.

The Federal Gold Match with Sierra Match King 168 grain bullets (buff and blue box) rated at 2600 fps measured at COAL 2.800 averaged 0.688.
The Federal Gold Match also with 168 SMKs (newer maroon and gold box) rated at 2650 fps measured at COAL 2.800 averaged 0.614.
Black Hills with 168 SMKs rated at 2650 fps at measured COAL of 2.800 averaged 0.682.

These were some of the most accurate factory ammos that I tested.
My particular rifle seems to prefer 168 match bullets.

Hand loads were tuned with a variety of different powders and data for equivalent velocity and depths using neck sizing instead of full sizing, and measuring using the ogive for seating instead of relying on OAL measurements (although I do still measure and record COAL for comparisons). The results for loads that are closest to the available factory ammo that I used are:
With Reloader 15 powder, 168 SMKs, 2650 fps at COAL 2.800 averaged 0.657.
With Varget powder 168 SMKs, 2650 fps at COAL 2.800 averaged 0.733.
With H4895 powder 168 SMKs, 2600 fps at COAL 2.800 averaged 0.580.
H4895 with the same specs but at 2625 averaged 0.587.
H4895 with the same specs but at 2625 and COAL 2.815 averaged 0.538.
H335 powder 168 SMKs, 2600 fps at COAL 2.800 averaged 0.595.
H335 with the same specs but at 2650 fps averaged 0.836.
N140 powder 168 SMKs, 2600 fps at COAL 2.800 averaged 0.452.
N140 powder with the same specs but at COAL 2.805 averaged 0.436.
N140 powder 168 SMKs, 2650 fps at COAL 2.805 averaged 0.395.

The N140 powder is the latest that I have been testing and it clearly is a good powder for my rifle. The average of 100 SMK groups shot to date, good and bad, is 0.537 so it is outperforming the other powders by a considerable margin. The average of 153 groups shot with 168 grain Nosler Custom Competition bullets is 0.518. so my rifle seems like the Nosler bullets even more than the Sierras.

As you can see, the data may have led me to believe some of those myths might just have had merit since varying velocity and seating depth seemed to help tune the barrel/stock combination for my rifle into an apparent node or two along the way and improved considerably on the accuracy I could get with the factory ammo that I could buy.

However, myths or not, using neck sizing, measuring against the ogive and adjusting velocity by adjusting powder measures seems to allow me to improve on available factory ammo for me and my rifle.

While I won't necessarily believe the myths now that you have clarified their questionable factual underpinnings, I'll probably keep using the techniques that seem to work for me to try and keep improving my rifle's accuracy since it seems to work given that I am probably doing something else wrong that mask the more theoretically valid approaches.
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Old February 4, 2013, 03:43 PM   #23
Bart B.
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Rimfire5, some comments for you. . . .

Sierra Bullets' never made any ammo; just bullets.

Barrels chambered for the .308 Win. typically last 3000 rounds for best accuracy from match grade barrels. 5000 to 6000 in factory sporter barrels. After those numbers, their owners typically start seeing accuracy degrade to the unsatisfactory level.

If one cannot get best accuracy with the .308 case by properly full length sizing it, they're not doing something the best way. It'll take a very close look at the details to find out what the problem is. The round count in your barrel's near the top of my list of probable causes. Another is what method you use to measure accuracy; group averages ain't all that great. Would have been better to shoot all those groups with a given load on the same target; instead of 5-shot groups fired 4 times, shoot one 20-shot group.
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