Working with Sniper’s Hide puts me in a unique position. A position we have been in before, however I wanted to make a training lesson out of the opportunity. I was tasked with testing the stability of a new ELR / 338 Monolithic Solid Bullet. There are some unique characteristics with this bullet, but the biggest one that effects me as the tester was the barrel being used and the limited resources in terms of the number of bullets available.
This bullet is designed to work with a special gain twist barrel. I happen to have one of the older designed barrel in 338 Norma Magnum for my Accuracy International AWSM. Once the bullet is tested and confirmed to stable, the plan from the manufacturer is to offer the bullet and barrel as a package.
My understanding is the twist rate is being refined and soon this bullet & barrel combination will be offered to both Savage Rifle Shooters as well as for the Accuracy International. The twist rate is 13–5.4, which means it starts at 13 and ends at the muzzle with a 5.4. It’s designed to over-spin the bullet so instead of a rotation rate of 200,000RPMs you are looking at something closer to 500,000RPMs. Now for the hiccup when it comes to me the tester, jacketed bullets will not work in this barrel. They will disintegrate when they exit the bore, and could even rip apart in my muzzle break, so I have to shoot the solid, monolithic (lathe turned) bullets out of the barrel in order to get to the target. With no data to start with, it’s all a learning opportunity.
My other really big limitation, I only have 8 of the finished bullets to test and I have to test them to at least to 1000 yards. That makes it really hard as I need the results on paper. So I was able to scrounge up 6 of the older style bullets from 2 years ago. This was gonna help me at least get close. The difference is, the new bullet is a 280gr and the older one is a 278gr, which is close enough to work, but still presents a bit of challenge. We’ll use the old bullet as a sighter and the new bullet for record to help the manufacturer.
Before we Begin
The first thing I did was swap the barrel on the AWSM, from my standard 338LM barrel to the Bartlein Gain Twist 338NM. Next I determined a load that was close without going too crazy. After all I had to shoot it, and didn’t want an issue from an unsafe powder charge. My initial data showed a Max Charge of 81gr of 7828SSC, so I opted for 79grs of this powder. Both sets of bullets were loaded together. So they were identical in every way but weight. The OAL, Charge, etc were all the same. The only difference the design.
Bartlein Barrels is our choice of barrels for projects like these because they can make any barrel we need. Test barrels from them are commonplace in the industry. They have computer controlled Rifling machines, these are not the old school Pratt & Whitney machines, but state of art units that can easily produce a barrel of this type.
Another difference it this, the bullet and bore were coated with a ceramic compound. The driving bands of the bullet have the compounded added as does the bore of the rifle. According to the bullet manufacturer, this will keep the barrel from wearing out. Time will tell…
On the range:
Once I got to the range I set up a standard NRA - F Class Target and made sure all the holes were covered so it was clean as possible. I then added a “Water Mark” using black duct tape so I had a solid horizontal line to hold my reticle. I needed a consistent hold point so I can record any variations in impact between the old and new bullets.
Consider using a Water Mark whenever you are doing any kind of accuracy testing. To include load development. A water mark is just a reference line so you are sure you are holding the reticle in the exact same place every single time. We can overlook some horizontal spread potential caused by us or the wind. But we want to minimize the vertical and determine which gives us our level amount of vertical spread.
Once this was done, I proceeded to bore sight the rifle. I started at 300 yards as the plan was to move from there to 600 yards then finally to 1000 yards. It took me 2 rounds total to get in the 10 Ring of the target. This was all done by reading the impact in the reticle and making the adjustment in the scope exactly as I read it. I am not measuring the impacts downrange on the target. I am only going downrange to verify and plot the position on paper, then I am returning to the rifle to measure the plot using the reticle. The reticle is a calibrated ruler 3 inches in front of the shooter’s nose. The another training point is the use of this to measure the impacts and adjust.
I fired one round of the test batch at 300 yards to make sure the bullet hole was round and they were flying true. Keyhole shots or the bullet hitting sideways would be indication of an unstable bullet.
At 600 & 1000 yards I repeated the process. Some bullets will be stable and then quickly start to tumble the further downrange you are. Straight and true bullet flight will have a nice round hole in the paper.
In the end the manufacturer was ecstatic with my results. Because the new bullet used .5 mils less dope than the lighter 278gr, he believe that proves his placement of the driving bands on the bullet and how they are reacting to the Gain Twist barrel. In my mind .5 mils was pretty significant. He never explained this to me prior to my testing and only explained his expectations after I reported the results, which is a great way to do it. My goal to was see if they fly straight and report my findings. His was analyze the data and make adjustments as necessary. Keeping me in the dark was a way to avoid corrupting the data.
We recovered one of the bullets from the berm and we can report the difference between it and a 175r SMK. Differences in terms of lost mass, 338 solid weighing 278gr the recovered solid weighs 276.6 and the Sierra 175gr weighs 123.6gr. Recovered from a dirt berm.
Moving forward I will have 38 more of these bullets to test at further distances. My plan is to take them out to 2000 yards at least. This is how a site like Sniper’s Hide helps manufacturers test and evaluate a new product before they are brought to market. We go out and do real world testing as the designer just doesn’t have the resources we have.
This is a work in progress, monolithic bullets are out there, several companies make them. They are expensive, but give the shooter an edge over jacketed bullets. It’s important to remember you cannot mixed Monolithic Solid bullets and jacketed bullets. The barrel must be completely cleaned down to bare metal before switching from one to the other.
Get in on the conversation regarding ELR shooting, Monolithic Bullets and our test by heading out forum for a Q & A.