Custom Rifle Loads

Peering through the scope, only one hole was visible on my target? I had already sent two rounds downrange with my .204 and wondered what was up? I grabbed the third round of this particular batch of handcrafted ammo and chambered it. Focusing again, the third round was off with a crisp trigger break and yet again I couldn’t distinguish any extra holes in the paper? I had to know! Getting up from my prone position, I walked 100 yards down to the target and sure enough, there was only one hole. Upon closer examination, I found what I had desired! Perfection in matching a gun with a round! I had punched the second and third shots right through the hole the first one had created. I had an oblong hole instead of a perfectly round one. It can’t get much better than that! I mass-produced that combination of powder charge, bullet and overall size and now every time I shoot that gun, I know what it should be capable of!

The purchase of a new rifle always brings excitement! The visions of bringing down that quarry you seek with your new rig fill your mind before you’ve ever even pulled the trigger on it. Slow down before just grabbing any random box of ammo off of the shelf and calling it good though! Your new rifle is a precision instrument capable of optimal performance if you’re willing to do a little extra work to make it shoot like it’s capable of. It’s amazing how certain rifles like one load more than others.

The amount of time, money and energy you can spend tweaking every little thing in the component make-up of a cartridge to make a rifle shoot differently is endless and can send your head spinning. With each thing you change, you get a different result in performance. For a bench rest shooter primarily devoted to punching paper, load testing will likely be much more in depth. For the shooter that just wants their rifle finely tuned for that moment of truth in the field however, it’s just a matter of matching the rifle to a consistently performing round. To keep it simple, first ask yourself what you want the round to be capable of doing. Is this for big game or for varmints? Fur friendly or does it matter? Once you’ve decided on the game you’ll be hunting with it, and what you expect the round to do, you can narrow down the bullet weight and projectile types to start testing.

Without going into the entire realm of all the different components you can add and take away to the recipe, let’s keep it simple and assume you already have your brass primed, prepped and ready for a charge and bullet seating. To start out, stick with the basics and try not to change too many things in the equation. Use the same brass, same primers and sizing for each round you intend to test. You can always go back later and change these things up if you aren’t happy with the results of what you get. Focus on staying within the specs of your loading manual and trying different powders, powder charges and bullets or bullet design to begin with. By focusing on just those variables, you’ll likely find the right combination to produce results that you’ll be extremely happy with for hunting intentions.

I recently acquired a Remington 700 BDL chambered in .243 that had barely been used and for the purpose of this article; I’ll use it as an example and detail the steps I’ve completed in the load testing process. Manufactured in 1974, with a 1 in 9 barrel twist, I topped it with a Vortex Diamondback series scope. My intent with this rifle is to find a load that I can use to deer hunt during Iowa’s late rifle season as well as take the occasional coyote with. Once I had my cases trimmed down to 2.045 inches and primed, I was ready to load them. I chose to stay around the middle ground with powder charge increments staying anywhere from a full grain or two above the recommended starting charge to below the maximum recommended charge. Middle ground has always treated me well personally and I’ve found that the hottest loads don’t always group the best. For example, when loading with Hodgdon 4350 powder for an 85-grain bullet, I loaded three cases with 44 grains and then I went up a half of a grain in powder to 44.5 grains for another three cases. My last use of this powder was for three more cases loaded with 45 grains for testing, even though I could have loaded an additional three at 45.5 grains before hitting the ceiling. I topped them with Sierra Gameking HPBT bullets and moved on to the next load.

I ended up trying three different powder choices with the 85 grain Sierra bullets in all simply because I had more of those bullets on the shelf. I chose to try two different powder choices with a 90-grain Nosler Spitzer bullet to see how it would perform and since I occasionally want to go coyote hunting, thought I’d start with one choice of powder for some Nosler 70 grainers that I had. For each different combination of powder, powder charge and bullet, I loaded three test rounds. In all I ended up with 54 rounds to shoot and 18 different batches for testing. One of the most important things to remember while building test loads is to make sure that everything you have done with each individual round you’ve created is accurate! Remember that the results of shooting these through your rifle will determine what you will later mass-produce for it. If anything is off with your powder measurement, cartridge length, documentation in the field or otherwise, then you will reproduce a lot of rounds that aren’t true to your original result. This is why it’s a good idea to hand measure each and every load you create during this phase and double check your case size and overall cartridge length. You want as much uniformity as you can with every aspect.

Now it was time for the fun part. Shooting! Just as I’ve limited the variables in selecting components to begin with, you’ll want to take out as many variables as you can when it comes time for testing on paper. Wind is a variable, so wait for the right time to do your shooting when the wind is very calm. Another huge variable is your shooting position. Whether you are shooting prone or from a bench, make sure that you have a stable rest to help limit your gun’s movement when you’re ready to squeeze the trigger. Be comfortable. If you are fighting the scope and your sight picture, you’ll throw some of your shots. An accurate testimony to the loads you’ve created and how they factually perform depends on your ability to pattern them honestly out of the gun limiting human error as much as possible. You’ll have to keep your point of aim the same for each grouping. Don’t change a thing about where you are placing those crosshairs while working on the same string of shots with one individual load. Lastly, be relaxed. If you are having a case of target panic or you are not comfortable in your shooting position change it or try shooting at a later time. You’ll need to give the loads you pattern every chance of being successful on their own.

Before I actually do my shooting, I make sure that I have everything in place. Have a tablet or paper next to you so you can write down which load you are shooting if you have multiple targets out in front of you and write down the velocity of each round sent downrange when using a chronograph. I love using the chronograph so I can see if my feet per second readings are corresponding with my changes in powder charges as I shoot. If you see a velocity reading that is lower from that of a powder charge from the previous string with less grains of the same powder, than you likely have a problem with your loads that developed back at the bench. Another added benefit of the chronograph is seeing how close each reading is in feet per second (fps) within each batch. I regularly have readings only vary by 10 fps from round to round loaded with the same powder weight and occasionaly get duplicate readings. It’s a good feeling to know that your loading was uniform and precise when you see the readings come out close to one another. Especially if that particular load grouped very well!

Take your time and don’t be in a hurry while punching paper. If you are trying to hurry you’ll accomplish two things. You’ll rush shots and throw them off and heat your barrel up, both of which contribute to inaccurate findings. It took me almost 4 hours to shoot those 54 rounds I tested. That’s an average of around one shot every four minutes. That may have been a little overkill but keeping your barrel as close to the ambient temperature as possible is important. You won’t be shooting a hot barrel at a deer, or coyote, so make sure you don’t throw a “flyer” on the paper because your barrel is flaming.

Once I had completed my shooting, I felt like I had an accurate record of what each load could do out of my rifle. Some were good and some not so good. I noted that twice in those 54 rounds, I felt like I might have caused a bullet to stray a bit because of human error, but otherwise everything felt good. It’s important to record every detail of the load, the weather and any other things that happen with each string of shots. That material can be kept and if for any reason down the road you want to start from scratch building another load for the rifle, you’ll know what you have already tested.

My worst group was a 1.975-inch spread produced by an 85gr Sierra bullet backed by 35.5 grains of IMR 4895. My best grouping came from that same Sierra bullet powered by 42 grains of IMR 4350 powder that only spread apart by 0.320 of an inch. That’s quite a difference! There were several other loads that produced at or near ½ in MOA at 100 yards along with several loads that couldn’t shrink down under an inch spread at that range. A 90-grain Nosler Spitzer bullet paired with 41.5 grains of Hodgdon 4350 powder measured a close second with a 0.450 spread and might be worth a second look. When I have several loads that are in close proximity of small group size, it’s not a bad idea to go back to the bench and build some more rounds of each of those well performing loads. Testing them again can weed out the best one for an individual choice.

When hand loading, I like to start with these methods and go from there. If a desired grouping isn’t accomplished with the components you want to work with, then you can go back and change things like seating depth, primers, etc. and see if the results are better. It’s good practice to examine all of your fired casings for signs of excessive pressure after you’ve shot them. Even if you are not hand loading, you can try several different brands of ammo off of the shelf. Your gun will tell you what it likes and I’ve had rifles that shot factory ammo close to loads I’ve worked up before. Finding a load that places every shot right where you intend it for the game you pursue will bring a smile to your face and a sense of satisfaction guaranteed!