Discussion in 'Ammunition & Reloading' started by zippygaloo, Feb 26, 2012.
1. How do I "work up a load"? And do I need a chronograph?
Well you start with a known load and adjust things as needed to get it to work best in your gun.
You can change brand of cases, case length, bullet seating depth, overall length, type of powder, powder charge, crimp or not, bullet weight, bullet style, bullet brand, primer, primer brand, I am sure I am forgetting some.
The only thing a chronograph is going to do for you is tell you the speed of your bullet. You can use that to help determine powder charge as your accuracy will change at some point with different speeds.
That depends on what you mean by that. Are you wanting the max load possible or are you after best load for a specific firearm.
Very broad subject but the better reloading manuals such as Hornady will help give you a general idea of what's involved in working up a specific load, objectives, etc. You'll always learn more as the years go by.
This document is an excellent, detailed writeup on how to work up a load for a specific firearm.
The Stickies at the Top of Sniper's Hide Reloading section have a ton of good information on loading for consistency and accuracy.
Once you get started, I recommend starting a thread here and let other people provide feedback and advice.
Aside from oasis' and sheepdip's frequent forays into unmentionables, for those of us who wish to help with (what I hope is) your intended venture, it would help to know what caliber you are playing with (and I will assume highpower rifle category):
I spent today "working up a load", and I've been 44 years at the reloading bench, and still do it (oasis and sheepdip: SHUT UP!).
Today's venture was with a gun that belongs to my dearest friend in Montana, and he hunted with factory loads this year and thinks he missed some long-range shots at Antelope due to not tuning his rifle, and using generic factory loads. The gun is premier quality: Rem 700 BDL Stainless Laminated, 7mm Rem Magnum. I brought the gun home to glass-bed it for him, (install a good recoil pad), adjust the triggger, and work up a nice handload for it in preparation for next year's hunt. I don't own a 7mm Rem, but had one years ago. The only thing currently comparable in my stable is a .276 Ackley (actually 7mm), that is considered to be a "better" (more efficient) 7mm, comparable to the equally efficient 7x61 Sharpe and Hart that won worldwide fame in the post-war years, and was the impetus for Remington to introduce their own "hopped-up" version. My Ackley gun was actually built by the master, P.O. himself. This is all beside the point, except to show that I basically was "starting from scratch" with this caliber.
1) Consult your books. (You should have more than one, 3-5 is nice.) Peruse recommended and/or "accuracy loads". These are only a guideline for what might work in your particular gun.
2) Try those recommended loads. Pay particular attention to primer recommendations, make sure your brass is absolutely identical (not only for brand, but times fired, trim length, etc.)
3) The overriding MAJOR AXIOM is that bullet choice will yield more instant results for accuracy than ANY OTHER change in components. Find a bullet your gun likes that is also compatible with your purpose (your trusty .270 will almost always shoot those Speer flat-base 100g hollowpoints like a bench gun---but smacking a muley's shoulder with one will very often disappoint). A book-recommended load (primer/powder) is a good test fuel-cylinder to find what bullet your gun likes. This exploration for a good bullet is where the major expense will be found. Find buddies that will give you 10-15 bullets (rather than buying a whole box) to try. This is also where patronizing regularly a small gunshop will help. I have never found one of those merchants that would not supply me with a paltry handful of bullets if they know I am coming into their shop regularly and spending money. The "good" bullets (one your gun prefers) will stand out immediately, with a book-recommended charge of powder/primer/matched brass.
4) Once you have determined one or two fine bullets (that meet your specifications for applied use), and overall length of cartridge (how far off the rifling should your bullet be for your gun) have been discovered preferred by your rifle, THEN AND ONLY THEN, start fluctuating your powder choice and charge. Once again, helpful buddies with varietal powders on hand can help you here to save money. (You have to be "hard-in" with your gunshop to get them to farm out small amounts of powder, but it can be done.)
5) After your good bullet is found (along with seating depth), powder type and charge is determined, THEN AND ONLY THEN, try different primers.
You do NOT need a chronograph. This from a guy who considers his chronograph his right arm. You are looking for what shoots well out of your gun. I do all this preliminary work PRIOR to firing up the Oehler. Mister Oehler is the coup-de-grace. He tells me WHY what I found to be good is good, and allows me to explore in more minute detail what might be better. I will be the first to say that the most consistent velocity load is VERY OFTEN NOT the most accurate load. Contrary to Newcid's very limiting assessment of what a chronograph does (it does so much more than tell you how fast your bullet is flying), the chronograph is ESSENTIAL! But ONLY essential at the fine-tuning stage. It tells you WHY what you found out is good (prior) is good, and then it tells you WHAT MIGHT BE BETTER. It allows you to actually see a pressure spike (delivered in velocity erraticness). It allows you to see how your primer change/bullet seating depth affects velocity and consistency.
This is a pretty generic breakdown. Had the cartrige and rifle been specified, it might have been more specific. It would not be the first time I have been nominated for (or achieved) a sitcky, but the first time I have (gently) suggested it on my own behalf. I invite the "old hands" who can still (much to oasis' and sheepdip's collective chagrin) work up a load to chime in, and add or subtract from this. I learned much today with the 7mm experiment: 10 hours total, and the shooting bench is 60 seconds' walk away. I figure about two more 10-hour days with this gun to find out what she is trying to tell me (okay, maybe oasis and sheepdip are on to a very appropriate analogy).
Start by reading The ABC's of Reloading. It will answer all your questions.
I use the optimal charge weight method.
First decide what type of application you are looking to build bullets for, plinking/hunting/shtf etc, and select an appopriate bullet. For every caliber there are a handful of commonly used bullets that have been known to work well for specific applications, what caliber are you loading for?
Then decide on a powder, again, if you give us an idea of the caliber we can point you in the right direction.
Then, take the maximum powder charge and subtract 10 percent. So for .308 Winchester using Varget Powder the maximum load may be 45.5 grains (just off the top of my head). 10% of 45.5 is 4.5. 45.5-4.5 = 41 grains. Now, start loading charges at 0.3 - 0.5 grain increments from the starting load of 41 grains. 0.5 grains are better to cover a bunch of loads quickly.
0.3 = 41.0, 41.3, 41.6, 41.9, 51.2 etc
0.5 = 41.0, 41.5, 42.0, 43.0, 44.0 etc
At this stage of the game we are looking for a general idea of what your gun likes to shoot. Without getting to into, there is something called barrel harmonics. The TL : DR version is that every barrel has a milisecond of relative calmnes after the tremendous shockwave from the bullet being fired, and it is at this time that we want the bullet to exit the muzzle. This calmness is affected by the powder charge you select for your loads.
Each gun has a number of "NODES." These nodes are powder charges that allow the bullet to exit the barrel in a a window of relative calmness. There are usually 2-3 per gun. (my 308 loves 41.0, 43.5, and 44.9 grains of varget) We are looking to tap into these nodes as a starting point to hone our accuracy loads.
So take your initial starting loads at the 0.3 or 0.5 increments we discussed earlier and head to the range. Set up your targets down range (usually 5-6 loads would be a maximum to test in a single batch. Number your targets. Then shoot your loads in this manner. 1 shot at target A, then 1 shot at target B, and on down the list. You do not want to shoot a single batch of one charge weight at 1 time. Rather, shoot 1 round from each charge weight until you finish. This will eliminate much of the shooter error and give you a better idea of how accurate a load can be. A good rule of thumb is
3 shots grouping: not enough to make a definitive decision
5 shots grouping: minimum amount to see how inherently accurate a charge can be
7 shots grouping: sufficient rounds to see how accurate a charge can be
Collect your targets and see where your groups were most accurate. Go home and make a new group of bullets but at a smaller charge weight revolving around the nodes that you discovered from range day 1. Eventually you will want to get down to 0.3 grains or 0.1 grain intervals to wring as much accuracy as possible out of the load.
After you narrow down your optimum charge weight, you can look to adjust the bullet seating depth. Many rifles prefer a specific gap between the bullet and the start of the lands and grooves of the rifling. Some rifles cough remington cough, have an excessively long freebore to prevent you from jamming your bullet against these lands and causing an overpressure.
The safest way to do this is to borrow or buy a bullet comparator to measure the distance of freebore in your gun. Then subtract the recommended distance (0.020-0.040) from "jammed" and start to load your bullets based on this number.
So say using my bullet comparator i find that with a specific bullet, "jammed" (contact the lands) is 2.500"
I would then subtract 0.020 - 0.040 from jammed and begin to load.
2.500 - 0.040 = 2.46
2.500 - 0.020 = 2.48
Start your loads and measure from the ogive at 2.46 (Or less), and then stop when your loads measure 2.48 at the ogive.
Many rifles have a maximum magazine length, so you must decide if you are willing to single load each round into the chamber, or if you want to utilize the internal or detachable magazine. If you want to use the magazine, you will be restricted to the maximum magazine length. Single loading each round will allow you to adjust the bullet seating depth to find the most accuracy.
Here is a link to the OCW method mentioned in my first post
Wow. Thank you all for the documents, links to additional information online and especially the detailed explanations. There is a lot for me to learn.
I'm going to offer a simple answer to the question "do I need a chronograph".
It depends. If you're going to shoot at fixed distances then the answer is no. Go ahead and work up your load staying within published Min/Max weights until you have one that is as accurate as your rifle is capable of. If you see no pressure signs such as sticky bolt, etc., just load and shoot to your hearts content.
The big issue is when you start shooting at varying distances and you need to know your muzzle velocity. If you don't then how do you calculate bullet drop when changing to longer distances.
The size and consistency of your groups will answer the questions regarding ammo consistency.
For me, a chronograph is an essential tool as I have to know the speed as I shoot at random distances using a carefully plotted ballistics chart/table based on my specific ammo. For someone that target shoots at the same distances all the time, not so much.
This is just the beginning for you. These guys are full of great info,just keep asking the questions.
I have about 100 rounds of those type loads to try out ,when the weather and my lazy *** get together and go to the range.
What's keeping you? I was at the range today and it was in the 20's. Had it all to myself. A good pair of "long john's" is all you need
Spitpatches Technique is right on... but I've also followed Design of Experiments / Taguchi Matrix to help optimize load development.
With DOE, I settle on a certain powder, and a certain weight of bullet for an experiment. Variables can then be: powder charge, primer, case, distance from lands/seat depth. The choice of which Matrix used depends on the number of variables & levels (ex. A level 3 variable would be powder charge of 45gr, 46gr, 47gr). The results to judge your accuracy can include velocity (with SD), and your group size (Average Group Radius).
Using DOE can help narrow your search for an accurate load by examining how a variable affects your results, all while using less ammo, and wasting less time at the range.
There's lots of information and tutorials on taguchi and design of experiments for reloading... just a google-away!
I was insulating the reload shed as to keep all my gear from rusting.
I keep the rust off my gear by using it frequently You were talking guns, right?
I knew this thread had potential.
RELOADING EQUIPMENT sheez
The guy in the local shop was talking about this with 2 20 something kids in the store,shaking their heads and trying not to smile.
if its your first time loading for said gun don't load a bunch until you test. I just picked up a 45acp and been working a load this week. The book says for my powder and bullet min is 4 grains max is 6.5. So what i do it load 20 rounds at 4.5,5,5.5,6,6.5 grains then go shoot.
results today was
4.5 grains didn't eject most shells not enough kick ( i kind of figured that.)
5 ejected almost all
5.5 ejected all and felt good
6 ejected all but had some kick so staying on target with quick shots was an issue
6.5 ejected but kicked like a mule
With that it looks like fancifully from 5.5 to 6 grains was what was the right load for me and this gun for quick stay on target shooting. Sure i can test by the grain but i am not looking for 3 round groups or 1/4 inch and 100 yards so close is good enough. I just got done loading 500 rounds at 5.7 grains. More tomorrow.
Just keep track on what you use for each gun. that way reloading later is spot on without forgetting what you ran.
Off topic, sorry.
Curious here what gun, powder, bullet weight your doing. I've been doing .45 for a 1911 and always started with minimum powder, and through 500 or so rounds have never had a FTE. I've done just fine staying in the lower half of the rcomended amounts in 9mm and recently .40.
pt 145 unique 200 r n
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