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Factory Ammo?

Late-BloomerLate-Bloomer Member Posts: 249 ✭✭✭
Several of my rifles perform quite well to extremely well using assorted factory ammo.

I am new to reloading, but I plan to reload very soon! I've been reading all my manuals & handbooks, but there are so many powder choices, powder charges for any one weight of bullet, really, just how can that be? I mean, I realize its a compilation of recipes presented so one might be able to find a given load for his specific rifle, but........

My question is this,

How do these large ammo mfg's decide on which load for each specific grain of bullet that they market. For example, .270 Win. 130 Gr. & 150 Gr.

With all the different combinations available, what is their criteria for the most optimum powder, load weight, in any given cartridge?

They must be putting their money down on an OPTIMUM POWDER & OPTIMUM CHARGE WEIGHT for a given Cartridge? Their own R&D has discovered (this)+(that)= reasonably excellent accuracy in most modern rifles.

Is there any such data around for the average reloader, especially for a novice, such as myself, other than what the common reloading manuals list?

What are the classic powders/loads for the .270, 6.5x55mm, .308, 30-06, 7mmRM?

Any replies would be greatly appreciated!!!

Thank you

Comments

  • perry shooterperry shooter Member Posts: 17,390
    edited November -1
    The powder used for factory loads are loaded to pressure spec's and the velocity may change slightly from one "LOT/ batch" of powder to the next. The powder we can buy for reloading is made to try to be the same burn rate for each "LOT/BATCH" because we as reloaders don't have pressure gages.I like to use a powder that will give good velocity acceptable pressure and fill the case to the bottom of the cartridge neck. Just because you work up a load with one can of say 4350 powder it might not shoot the same with the next can of 4350 if the lot number written on the can is different. Most target /bench rest shooters in both pistol and rifle buy large supplies of the same lot number bullets , powder , and primers and then they don't have to TUNE their load to the gun but once.
  • Late-BloomerLate-Bloomer Member Posts: 249 ✭✭✭
    edited November -1
    quote:Originally posted by perry shooter
    I like to use a powder that will give good velocity acceptable pressure and fill the case to the bottom of the cartridge neck.


    thanks perry shooter-

    BTW, how might I get a lists of powders that would fill my cases for the cartridges mentioned and then go from there. I've heard that several times before from several posters about powder/case capacity. I believe it was referred to as, load density.

    What are the benefits of a powder that fills the case up to the bottom of the neck vs. a powder that only fills 1/2 of a case per se.

    How does a newbie like me determine which powders will fit that criteria. Is it just from trial & error from studying various loading manuals; or are there time-proven classics that have been documented somewhere?

    Thank you, sir!
  • perry shooterperry shooter Member Posts: 17,390
    edited November -1
    Hello all powders have different burn rates with Bull-eye and 231 at the fast end of the scale and 4831 near the other end "SLOW" The reason I like a powder that fills the case is then it is impossible to accidentally fill the case with too much powder and thus have a dangerous over load This and the fact that the slowest burning powder that will just fill the case for the velocity you are after in any given cartridge will give the lowest pressure thus longer case life and barrel life .The reloading manuals normally have the slowest burning powder with the largest grain weight of powder for those powders listed and that will give you an idea of how many grains your case will hold . slower powders will most likely not be listed. Feel free to email me r Cheers Perry Shooter
  • JustCJustC Member, Moderator Posts: 16,035 ******
    edited November -1
    First of all, the ammo co's use different criteria for working into a load weight. They use a target PSI as the basis, and then work the powder up to that PSI in any particular chambering. Also, they use "married" powders which we can not get. There are several burn rates mixed to acheive a desired load density which will produce the target PSI. Handloader work the opposite way,..we pick a bullet and a compatable powder, then load the ladder until we find the accuracy nodes, and stick with that as the load we use.

    filling a case to a high load density serves to promote a very uniform ignition from round to round. When the case is close to full, the ignition will start at the base of the powder column and work it's way fwd to the bullet very uniformly. A low density will leave a lot of air space inside the case, which as the bullet is taken from vertical to horizontle (in the rifle magazine) the powder will then lay down and allow the air space on top of the powder load. This random settling of propellant with different shapes and air in different places from round to round, will affect the burn rate in such a way as to become less consistent from round to round. That change in ignition affects the pressure curve from round to round, which will then directly affect the MV, which then creates larger spreads in Extreme Spread as well as Standard Deviation. When these spreads grow, the groups will grow by default.

    also, if too little charge is used, and the load does not fill at least 50% of the case up PAST the flash hole, this can allow what we call the "secondary ignition effect" which means the flash from the primer will jump across the top of the entire load igniting it completely rather than initiating a burn from case head to case mouth. When that entire charge is ignited at once, it will cause such a quick spike in pressure, that the bullet, for lack of a better way of saying it, the bullet just can't get out of the way fast enough, and something has to give. This will usually be the action and magazine that blow, and the shooter collects the remainder of the escaping gasses in the face and hand located near the floor plate.
  • Late-BloomerLate-Bloomer Member Posts: 249 ✭✭✭
    edited November -1
    Hey JustC-

    Thanks a bunch for the explanation, I think I got the picture now. I don't think I'll be wanting any of that "Secondary Ignition Effect" happening in my action, right up next to my face though!

    GREATFUL!
  • bpostbpost Member Posts: 30,898 ✭✭✭✭
    edited November -1
    If you look at a reloading manual some powders stick out as being efficient for that particular cartridge. They tend to give high velocity for the amount of powder used with a load density over 80 percent.

    Look at it this way, powder X gives you 3,250 FPS and takes 59 grains to do it. Powder XX gives you 3,190 FPS but takes only 51 grains to get the job done. In this case powder XX is very efficient for this case/bullet combo.

    The .270 is a offspring of the 30-06 slow powders like IMR7828, H-4350 and H-4831 will tend to give the best performance in this size case/bore. Your gun will pick the powder, load and bullet combo it likes best. The only way to find the sweet spot is to try several powders and bullet combos.

    Don't make a common beginner mistake of using the maximum FPS listed as a sign of efficiency and accuracy, it may be misleading. I never saw a groundhog that was concerned about the difference in impact that 150 FPS muzzle velocity makes.

    Go for nice round groups that you can repeat as a sign you are on the right track. Seating depth and charge refinements will do the rest in getting peak performance out of your hand loads.

    GOOD LUCK, happy safe shooting!
  • wanted manwanted man Member Posts: 3,276
    edited November -1
    okay, I've wondered for quite some time:
    Do you know of any INDIVIDUALS who "marry" their own powder mixtures or experiment with the procedure?
    No need to read between the lines, I'm honestly curious if any individual is so "deep" into reloading that they try their own "mixes"?
  • JustCJustC Member, Moderator Posts: 16,035 ******
    edited November -1
    some of the guys using the Savage 10ML smokeless powder muzzle loaders are using "duplex" loads,...(one powder dropped over top of the first powder) but other than that I havn't talked to anyone who has personaly "Married" any powders and fired them. Remember the factories have "pressure" barrels and actions made just for checking pressures with new mixes. If it blows up,..they get another one. Also, these actions are so large and the barrels are so large, that they can contain huge overpressure loads with no ill effects. The guages that record the pressures will tell them that past any certain point, the pressure is too high for manufactured firearms which usually ends up for rifles with a TOP END of 65K psi. Pressure signs on caseheads and sticky bolts just start to show up at 70K psi,...keep that in mind. Once you see the signs clearly,..you are past max by a fair amount.
  • sandwarriorsandwarrior Member Posts: 5,599
    edited November -1
    Late-bloomer,

    My own take on factory loads is "What will the public buy?" For instance you can hardly find any .257 Roberts in any store nowadays in anything but 117/120 gr. We used to be able to find 87 gr. bullets everywhere. It's a kind of goofy thing because all of the older .257's had either a 1-12" twist or a 1-14" twist. Those twists will stabilize 100's and 87's. But, you need a 1-10" twist to stabilize a 120 gr. It's a case where companies don't want to seem to go head to head with the .243 or 6mm maybe.

    That's the first thing I consider when I'm reloading. Is the twist in my rifle going to stabilize what I'm shooting? Secondly, what are you shooting? For game pick a performance bullet. For target shooting pick an accuracy bullet. For varminting pick a light accurate bullet designed for fast terminal performance instead of one for game.

    The powder loads that people use are all good points. One thing I think was left out is that lighter loads of faster powder where the case isn't uniformly filled will not only affect MV is will affect barrel harmonics. In most modern loads you are in the 50,000 psi range, and even though powder burns it does so at the rate of a slow explosion. That will send a vibration down your barrel. If the powder stack is slanted too far it will want to send a vibration going up and down down your barrel. Getting the harmonics to match is what I like to look for when reloading. What I like to do is work in moderately slow powders for the case and then use faster powders. I never usually use the slowest. Something to look for and avoid if you can concerning slowest powders is MUZZLE BLAST. You will typically find it with too short of barrel for caliber rifles. Like using magnum powders in a 30-06 or .270 Win case. The escaping gases come around the bullet as it leaves the barrel and affect accuracy. The only way to use super slow powders is to have a super long barrel, i.e. 26-30".

    The best poweders I have found for the rounds you listed are 4895, 4064, 4350 VV N140, VVN150, and 4831. The military uses RE-15 for the 118 Special Ball ammo. It burns right around 4895/4064 speed but gives higher pressure.

    This is a good subject and many of us could go on and on about what to change where to change etc. But I think you have a lot of good replies here. Take some time and soak them in. -good luck
  • Tailgunner1954Tailgunner1954 Member Posts: 7,815
    edited November -1
    quote:Originally posted by wanted man
    okay, I've wondered for quite some time:
    Do you know of any INDIVIDUALS who "marry" their own powder mixtures or experiment with the procedure?
    No need to read between the lines, I'm honestly curious if any individual is so "deep" into reloading that they try their own "mixes"?

    I personaly know one guy that "kinda" does, and have seen on another forum a second guy that "mixes", but they are both using a small charge of fast powder as a "booster" charge under a large charge (275+gr) of slow powder.
    In years gone by (back when Phil Sharpe* was still in diapers), a small charge of smokeless powder was often placed under the main BP charge to reduce fouling by benchrest shooters.

    *Phil Sharpe wrote and published his first reloading manual before WW-2.
  • perry shooterperry shooter Member Posts: 17,390
    edited November -1
    Hello wanted man and others that have raised the issue of married powders . At the chance of giving the fact that I am an old F^&T back years ago many people experimented with DUPLEX loads with 2 different powders in the same case for their reloads the idea was first one powder and then another and they were supposed to stay separated [?][?] some people even used a card separator [V] but this was when there was very little to chose from in powder types as most were military surplus that was from pulled ammo. Today we have over 100 powders to chose from and you could spend a life time testing all of them that COULD be used in any given cartridge. The closest I ever came to married powder was I load large batches of match grade 45ACP and buy large lots of the components bullets primers powder That I need I make sure I buy at least 10,000 bullets and primers at a time. But with powder I buy 8 pound kegs of Bulls-Eye Then I work up a load with this lot of bulls-eye This left me with about 1&1/2 pounds give or take depending on the charge of powder left over with every batch of 10,000. After saving up about 25 pounds total over a number of years I mixed them all together old green bulls-eye then newer yellow and later light and dark gray bulls-eye in a clean plastic drum and slowly rolled it around on my driveway "did I mention I am CHEAP" I then worked up a load that happened to be part way between the load with the 1970's green powder "HOT" and todays"MILD" gray powder[:p][:p][:p] It ransom rest tested as good as any I have ever shot and I am now using my DUKE'S MIXTURE for the last 2 years. [:D] I would never mix types of powder say a flake and ball or tube and flake but if you pour out some ball powder you will see many different sizes of balls "IS THIS A MIX" some of the older then me shooters did not like ball powders because they swore that the small balls would in time all go to the bottom of the can and be a faster burn rate and this could cause high pressure[xx(][xx(] Your mileage may vary
  • alleybatalleybat Member Posts: 40 ✭✭
    edited November -1
    Hi Late-Bloomer, I have a pet load for the .270 winchester you might like: 130gr ballistic tip, 58.0 gr Hodgdon 4831sc,CCI BR large rifle primers[:D][:D][:D]It has low pressure @ 3000 f.p.s. You will like this load!
  • JustCJustC Member, Moderator Posts: 16,035 ******
    edited November -1
    that is my exact load except for the primer,...I use standard CCI LR primers.
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