Well after many delays and working with some other rounds tested on the same day I finally have the numbers put together. Of course now you get to read some rambling before I serve up the main dish. I don’t like Me and Joe Went Shooting Formats nor do I like a bunch of colored charts with line diagrams all over the place though I can do either.
The rifle shot was an 18” upper build by Ritch’s Precision Guns using an 18” 25X45 3P barrel from Black hole. The lower was one that I use in my F-Class matches with the good Giselle HS Match trigger. All rounds were fired off a front pedestal and rear bag. I put a 24X Leupold target scope on the upper for the testing as removing my old eyes is always a good idea. Speeds were recorded by a LabRadar set up to give me muzzle velocity readings. The unit is quite nice as it is virtually unlimited in its shot string numbers and it lets me get shooting in about two minutes once I get my targets set up.
All cartridges shot were made up using Speer once fired nickled cases. Necking up was done with a 25X45 die, non-small based, from CH4D with a Hornady generic 25 caliber seater seating the bullets. No cases were crimped and CCI 450 primers were used in all loads. Powder dispensing was done via an RCBS Charge Master one at a time. COL was determined after checking the distance to lands. The barrel has a SAAMI chamber so the throat is quite generous and I was not in danger of jamming the lands at 2.300.
I selected three bullets to shot. The Hornady 87 SP, the Sierra 90 GK and the Hornady 117 RN were the choices for this trip. The 90’s were used for sighting in, the 87’s were handy and I had never shot one in that weight in my 25’s and the 117’s were, of course, the main focus for this exercise. Loading was straight forward with no surprises. The upper has an adjustable gas block so I was not concerned about reliability.
I did the initial sight settings using the Sierra 90’s. Seven rounds were put down range with a couple up close and then out to 100 yards. The velocity was nice at 2775 and the cases looked nice with no swipes or glaring primer problems. I got a three shot group at 100 that was not impressive but then a load done with by the WAG method rarely is.
Moving on to the 87’s I had decided to play with lengths of 2.260 and 2.2300. This bullet looks nice but I did note that SHARPS went for the SPEER version. I had no Speers locally in that pill and as I shoot a ton of the Hornady 87’s in my MM’s I figured it would give me some comparative velocities. I knew that BC would be lower in the 257 vs. the 243 but what the heck.
With AA 2200 my top speeds hit 2804 and with AA 2230 I managed a very respectable 2903. Both speeds were at 2.300 but they both had a 25.0 charge so that was a bit of cheating. Backed down to same same weight of 24.5 with both powders I had a 2772 with the AA 2200 at 2.260 and a measly 2771 at 2.300. The AA 2230 gave me a 2840 at 2.260 but when bumped up to 2.300 it pegged at 2869. Twenty nine FPS more for the longer length was noted. Across the board the 2230 was about 100 FPS faster than the 2200. I pretty much expected this as 2200 for me has rarely performed all that well with the heavier pills in my 24.
I found that with this bullet I was not getting any accuracy at all. I suspect there is something at work involving the length and the bearing surface. I know that others have shot 87’s with great results so I will lay this one at the feet of the ballistics gods. Speeds were fine but being fast and last doesn’t put meet in the freezer or Gold around my neck.
It was hot so I took a break after the 87’s were shot. At that point I had forty seven rounds down the tube. I debated cleaning but decided to let it all hang out for the next sixty rounds of the good stuff. A couple cold swigs of water and some beef jerky and jawing with the other shooters got me relaxed to carry on the testing.
The 117 RN bullets from Hornady look just like the old 30-30 rounds of my youth only smaller. Interestingly when seated to 2.260 they were right on the canneleur almost like they were designed for this cartridge. The 2.300’s were a tad in front of the case mouth but there is plenty of shank to work with on this one.
I stated out with the short AA 2200 loading at 21. And after the first five I was starting to look hard through the scope. It wasn’t bug holes but it sure looked better than the 87’s. Continuing on with these I was getting what I considered OK for the old world deer gun but nothing that got my long range juices flowing. I did get one load that was down at 0.785 and that one will get a reshoot on a later trip. I found speeds between the 2.260 and the2.300 were very close. I did bump the 2.300 to 23.0 and hit 2405. Not screaming but usable.
I had thirty rounds left using RL 7 and while I knew this one was a bit fast and would have like lighter bullets on top but I wanted to see. Speeds were not as high as the AA 2230 but that was expected. The first five looked good and I had hope that good things would show up. I shot the next two 2.160 groups and I was a happy camper. Speeds weren’t great but the cases showed virtually no pressures so maybe I can bump up. I followed these up with the 2.300 loads. This was a very interesting set of loadings. The extra 0.040 put the speeds lower but opened the groups. Less pressure at longer loadings was obvious thereby demonstrating the reverse bell curve of pressure vs. overall seating depth in relation to the lands. Even opened up the two lower loads would be devastating to any Minnesota whitetail or South Carolina hog.
This is a quick overall compilation on the various bullets and speeds.
The best group shot with AA2200 and the 117 Hornady.
The 117’s with RL 7 at 2.260. The faster it went the better it liked it.
The 117’s loaded longer at 2.300 using RL 7. Notice how the groups opened up by increasing the COL by 0.040.
Overall the test was very informative. I have my curiosity peeked now as I have multiple 90 grain hunting quality bullets I will be looking at this round. I want to look into the lighter varmint loads too so I can shoot a few PD’s this summer beside the 6X45 and see how it does. More time and testing will tell where the bug holes appear.
Greg
