Reloading .308 / Finding The Best Accuracy

Reloading enthusiasts often have their own methods and procedures, but they all end up adhering to some basic guidelines to ensure safe reloading and operation of their firearm.


Stats: Hornady 178g A-Max, BC .495, OAL 2.780, Stability 2+, 40gr Varget, 2450fps, 100m zero, transonic stable well past 1000m.

The following are just the highlights and key points I would like to share as I walk you through my journey at reloading the Hornady A-Max 178gr bullet for the 30 caliber platform. Just as a caveat, Hornady does not make the A-Max any longer, but they have replaced them with a newer version known as the Hornady ELD series with an even better reported ballistic coefficient. But, for those of us who still own these bullets, they ought to know they are still quite viable as a hunting round. The reason, in case you may be wondering has to do with the properties of the polymer ballistic tip, which would suffer from heat issues resulting in deformity at terminal velocities (very long ranges) beyond 500 meters approximately. The new ELD bullets are reported to be more heat resistant, resulting in better long range accuracy. For those who do not intend to shoot long range, this will not even be a consideration. As a side note, I would take these same steps to load the ELD rounds.
A-Max 178gr ELD Match 178gr

Equipment needed/recommended: Reloading dies, press, calipers, powder measure, weight scale, powder funnel, case trim tool, primer pocket tool, priming tool, case lube, reloading handbook.

I started out by acquiring some quality Hornady brass. With reloading, this will often be the most expensive part, especially if you are the type who prefers match brass and understands how many uses you can get out of quality brass versus the really cheap stuff.
The bullet you choose will determine your load parameters. I have chosen the Hornady A-Max 178gr in this case.

Be certain to use a reputable source for your load data, like this Lyman reloading handbook. It's really great to find the exact bullet I am loading, too. I often start out with a lower charge of powder and rarely go directly to max unless I am already familiar with the load I am making. For my load, I am going with a strong 40g of Varget powder. This will give me approximately 2450 velocity and create 44,000 pressure at the muzzle. Different powder will grant you various possibilities, and understanding this will give you the key to success when reloading (not all powders are the same). Your reloading handbook should list the velocity and pressure for each powder.

I prefer to use a hand priming tool, instead of a press mounted priming tool because I like to feel each round and achieve the most precise results. If I were reloading bulk target ammo I wouldn't mind as much, but for match grade hunting ammunition I prefer hands on, slow and steady.

I set up the press for my specific load, adjusting the dies appropriately. I will often test one round without a primer or powder charge and measure.
I want the completed round to fit into my magazine and to function properly, so I never ignore the OAL specs listed in the handbook. I will also give a 24 hour waiting period and re-measure on loads which approach maximum charge. You do not want to press down and seat a bullet into an overfilled cartridge case, and you certainly do not want to fire it. No crimp, thank you very much.

Using a head space gauge for your brass is extremely important on necked rifle cases. This is a Lyman head space gauge, and typically I would check the brass after I resize and clean the case lube off each one. In this photo I am using a case I have already primed just to show you, however. This gauge will accurately and quickly measure low/high for each end of the brass. With new brass, it's not really as important, but it's still useful for those who may not be accustomed to reloading and may have set their resizing die incorrectly. And yes, even with new brass I resize.

Clean those primer pockets on used brass.

I use this Lee case trimmer (Deluxe Quik Trim) with the appropriate die even on new brass when reloading necked rifle rounds (but not on handgun cartridges). I always keep them stowed away in their cases when not in use to prolong life. The blades on the trimmer can be easily damaged. It's definitely one of the best tools, it allows not only for properly sized brass, but chamfers the brass nicely also. This will allow for a perfect seam against the bullet when seated, resulting in proper pressure, expansion, and improved accuracy.

The powder you use will have to be set up in your powder measure, and I ran at least a dozen times to make certain it was right. Having a good setup helps, and this works for me. Granted, it's not a super expensive high tech setup, it just works.

I always write the load data on the box I use for my ammo. Using clear tape, it can be removed easily, and a second layer of tape will ensure the date remains intact.

I like to keep track of my load data. It may be months or years until I reload the same thing, so it is nice to pop right back in and be at full competency immediately with the help of this data.

A Mildot Master ballistic tool requires no batteries. Works for those of us who prefer mils and the insert also can be flipped for the MOA/yard civilian types.

This is all just way too fancy for the average Joe hunter type, but if you want to make the first shot count every time...The JBM link will provide you with everything you need to make your own ballistic charts and tables...Yes, mine are hand written and not a printed copy. Your data will vary from the general readout as you shoot.
Get to know your ballistic data. JBM --create charts and customize to your preferences. Copy and paste into your document editing program and save for printing or copying later. Do this for each temperature range you intend to be shooting. For example, I often create charts for 30 degrees F and higher, every ten degrees until I get to 65, then every 5 degrees until I reach 100 F.

Get some range time! I need more myself...

Is your bullet going to be stable? JBM - Calculations - Stability

Know your rifle, its twist rate, test fire at range how you plan to shoot in the field. If using bipod, test with it at range and zero with it at the range. Your rifle harmonics will change with every alteration of your shooting stance, position, and any object the rifle may be resting on. Remember, ballistic data is just an averaged value using formulas (even though they are very close) and it's up to you to acquire the most precise data from actually firing on the range. You can even go crazy and factor in humidity or even the Coriolis effect (but I'm guessing you don't want to do that) if you are worried about hitting your mark at 3000 meters.

 

Excellent introduction to the reloading process..

I have a single stage press (less change of my making an error). And, I like it that way.

Reloading is serious business. There are many areas of the process which can lead to damaged firearms and injury if you are not careful. That said it is an enjoyable process for me. It relaxes me, allows me time to myself and forces me to adhere to a strict operational procedure.

 

Our friends here have more scoop on handloading if you want to know more.
The Handloaders Bench

 

Yup, Been ReLoading for 60+ years, both as a Hobby, AND as an OEM Ammunition Manufacturer With a Class 6 FFL...
Consistency is the Key to Reloading.... Do it RIGHT, and exactly the SAME WAY, for each Cartridge, in a Lot... The more attention paid to Consistency, the better the accuracy of you product.... If you just want to move Lead, Down Range, that is one thing, HOWEVER, if you want High Accuracy, Repeatable Consistency, Especially at Long Range, then you need to make each round, EXACTLY Like the one before... Not just "Close" but at the absolute Limit of your capabilities... There are "Tricks of the Trade" that can help with that... Case Dimensions not just within Tolerances, but EXACTLY the same, including Volume.... Projectiles, not just from the same OEM Lot, but separated into LOTs, by weight, down to the .001 Grain... Powder NOT just close to the same weight, but EXACTLY the same weight, down to the .001 Grain.... Projectile Seating Force exactly the same for each round, and exactly to the same Depth, in the case mouth, down to the micrometer in overall length. These are just a few of MANY "Tricks of the Trade" that are used.... ALL it takes is TIME and Patience...

 

Some twist rate/bullet weight info for .308 I use:

.308
- 7" * for heavy VLD bullets and/or subsonic ammo.
- 8" for bullets heavier than 220 gr.
- 8" Ratchet rifled 4 groove
- 10" for bullets up to 220 gr.
- 10" * Ratchet rifled 4 groove
- 12" for bullets up to 170 gr.
- 13" * Ratchet rifled 4 groove
- 14" * for bullets up to 168gr.
- 15" * for bullets up to 150 gr.
- 17" * for bullets up to 125 gr.

I have my A-Max load set up for the 1:10 barrel, and if I wanted to achieve max stability with a lighter bullet (such as 168gr) I would need a 1:12 barrel. I prefer the 1:10 because I can shoot my 190gr heavier loads as well, and heavier bullets do reach out the farthest. But, for every day hunting (which for me is never beyond 300 meters) it's not as crucial to be worried. I just like to have the very best arrangement for that day when I really do need to reach out past 1000 meters. I wouldn't ever try to take an animal at that range, so you know I am talking about Red Dawn gobblygook.

 

Yes, for the professional competition types those are all very important. The thing is, our bodies and our shooting abilities factor in greatly, too (not to mention the wind) --far more than .001 grains of powder. Again, to the competition types, it's all critical. They can also be some of the most superstitious bunch in the world, and the entire genre is laced with elitists at every corner, too. Just so everybody knows, I do not claim to be a professional, an expert, or any kind of guru. This is only my journey and you can choose to take it as is or seek information elsewhere, like Ghrit pointed out.

 

I have Lapua brass, no difference except the price. But, I can probably get more runs out of the brass. Sometimes I wish it would improve accuracy!
Hornady match is sufficient. I'm not entering any competitions, no need to tighten groups if I can hit the target already.
That's the difference between an elitist and a common man.

 

Mil based rounds are usually NOT reLoaded, when used in combat, but left where they lay.... or swept up for salvage on .MIL Ranges, and sold as such.... but your point is also very valid if you are reLoading for High Accuracy..

 

UPDATE: Do not buy this brass.
Starline Reloading Brass 308 Winchester Match - MPN: 308Match (50)

I've only ever used Hornady match in recent years, but due to it being hard to find at times, and because this order is only for reserve ammo and range testing, I thought it was worth the effort to try it out, but the brass primer pockets were all too small. Ordinarily, I'd just use a reamer and hand ream it out, but this stuff was seriously too small. I even tried to drill it out, that's ridiculous!
Again, do not buy this Starline brass, ever.