Now that I had my suppressor, the first order of business was to check existing loads to see if they still worked.
After that, all new loads would be developed with the suppressor on the rifle.
6.5 PRC
Hornady 143 grain ELD-X
I loaded up a few of these at various seating depths–using a powder charge I’d discovered earlier–and went back to the range.
This was the first time I’ve shot with a suppressor. It was quiet–you hear the supersonic crack of the bullet, instead of muzzle blast.
Point of impact moved down an inch and a half at 100 yards. The factory ammunition actually shot a little better with the suppressor, picking up an additional 10 fps.
A quick re-zero and I was ready for the seating depth test.
I expected the .010″ group to do well again, but the first shot was a flier. The barrel was warmed up (and so was I) so I was at a loss as to why that first one went wide.
Fortunately, I saw another decent group seated at .090″: no fliers and very consistent velocities (standard deviation of 2.6 fps, if you’re into that sort of thing). I’m going to declare this the winner for now and load more to test over the summer.
Barnes 127 grain LRX
Having abandoned an earlier attempt to load these bullets with Hodgdon H1000 and magnum primers, I decided to try the same powder/primer combination I’d used with the Hornady bullets: Hodgdon H4831SC and Federal large rifle match primers.
I found an acceptable load at 53.5 grains of H4831SC, just under 1 MOA (1 MOA = 1.047″ at 100 yards). It was faster than the factory load, with consistent velocities.
There was also an interesting “double group” approaching max charge weight at 54.5 grains. I’ve seen these before: they can be caused by incorrect seating depth, excess powder charge, damaged/loose optics, mirage off the suppressor, poor trigger technique, etc., etc.
Having shot three bullets into one hole and two a half inch apart, an inch away, I was tempted to look at that 54.5 grain load more closely but decided against it.
Too many variables.
I tested the LRX bullets loaded from .050″ to .150″ seating depth at .025″ intervals.
The .100″ seating depth shot best and showed uniform velocities (3.8 fps SD).
More accurate than factory cartridges and almost 40 fps faster, this is my Barnes bullet load for now.
Berger 156 grain Elite Hunter
My go-to accuracy load in several rifles has featured Berger’s VLD (“very low drag”) hunting bullets. They’re sensitive to both powder charge and seating depth, but once you get them zeroed in–look out.
Berger has since developed the Elite Hunter line: less sensitive to seating depth than VLDs, with an improved ballistic coefficient.
The internet was absolutely abuzz.
Berger keeps new load data fairly close hold until they feel comfortable publishing it on their website, but will send it to you if you call and ask.
Phil at Berger/Capstone tech support was very helpful and emailed me Quickload data for Elite Hunter bullets in both of my new rifles.
Before testing these bullets, I upgraded the scope on this rifle to the same Vortex 5-25×50 I have on my 300 PRC. The extra magnification will prove helpful in case I let elderly people (like my brothers) shoot this gun.
While I was at it, I added Mountain Tactical’s 20 MOA scope rail and their billet aluminum bottom metal. The rail gives you extra elevation adjustment for long range shooting; the bottom metal provides extra rigidity and a larger trigger guard (in case you’re shooting with gloves on). I had both of these upgrades on my previous Tikka and am a fan.
Time for powder charge testing.
I showed up at the range and realized two things: 1) these loads just exceeded magazine length, and 2) I’d forgotten my suppressor.
I thought about slinking back home with my tail between my legs, but decided that after getting up early and driving 27 miles I was going to SHOOT, dammit!
I sighted in the new scope, then shot five different loads of H4831SC, single-loading each round.
My rifle likes these bullets. All but one of the charge weights shot sub-MOA, and all except one yielded single-digit SDs.
Unfortunately, the best group (half-MOA with 51.5 grains of powder) had the worst SD: 12.3 fps. Normally I’d accept that, but I prefer single-digit SDs for long-range loads.
Strictly speaking, I should’ve repeated the charge weight test with the suppressor installed. However, I was hoping to get lucky again with the 51.5 grain load, and maybe find single-digit SDs at another seating depth.
For the record: hope is not a method.
Before loading more ammunition, I ordered a Hell’s Canyon Armory (HCA) magazine and bolt stop that would allow me to feed longer Cartridge Over All Lengths (COALs) from the magazine.
I was initially befuddled by the Hell’s Canyon website, so I called them. Mike, the proprietor, took my order over the phone and promptly sent it down.
I’d loaded the previous test bullets to .045″ off the lands, which ended up being slightly too long for the original magazine (max length of 3.070″). My new HCA magazine allowed me to load out to 3.410″ COAL, well beyond what I needed.
With the new magazine in hand, I loaded another batch of the 51.5 grain load at .015″, .030″, .045″ (again), and .060″ off the lands per Berger’s recommendation. I also loaded five at .075″, just in case…
The longer bullets fed flawlessly through the Hell’s Canyon magazine.
The factory bolt stop worked fine, so I left it on and put the HCA part in the spares drawer for now. I’ll probably install it the next time I have the action out of the stock.
I shot the seating depth test after a quick re-zero for the suppressor.
I started with the .075″ depth, then .015″, .030″, etc., up to .060″.
I waited until I finished testing before moving the scope two clicks left, onto the bullseye.
Once again the .045″ seating depth shot well but failed to achieve a single-digit SD. All of the other loads shot single-digits. The barrel was getting hot by the time I shot the .060″ load, which may have hurt accuracy.
.015″ and .030″ seating depths yielded the best accuracy: the latter showed less vertical dispersion, while the former had a slightly lower SD (6.3 fps vs. 6.4). I tossed a coin and went with the .015″ load.
It turned out that I didn’t need to redo the charge weight test, after all.
What do you think?