7mm Valkyrie AR
The 7mm Valkyrie AR is a wildcat hunting round being developed for the AR15. It is based on the 6.5x47 Lapua case with the shoulder pushed back to allow it to run in the ar15 at 2.295 oal and necked up to 7mm. Case trim length will be 1.596-1.60 and case capacity is 42.6 grains of water.
It is designed around the 140 class of bullets which should be pushed to 2750-2850 fps from a 24" barrel. Most 150 and 160 class will also be able to run in it with the 160 sierras being able to run at 2.25 oal so they will work perfectly in standard mags. Estimates are for 2600 fps from the 160's. 120 class bullets should be in the 2900-3000 range and the 110's in the 3000-3100 range
Cartridge overall length 2.295 inches
Case trim to length 1.596-1.6 inches
Shoulder measurement with hornady 375 adapter 1.305 on fresh cases.
26” actual data
120 class 3000 130 class 3080 max
140 class 2875 150 class 2670 not max
160 class 2660
168 Berger 2675
24” actual data
110 class 3075 not max 120 class 3000
130 class 3000 140 class 2850
150 long range ab 2700 160 class 2660
168 Berger 2625
20" Actual Data
120 sierra 2860 not max 130 speer 2800
139 sst 2690 145 speer 2630 not max
160 fusion 2437 168 nosler 2416
16” Actual Data
110 TNT 2843
120 sierra 2804
130 Speer 2800
139 sst 2700
140 nosler bt 2600
The 7VAR with the 2.295 oal PRI 6.8 magazines work best allowing 7 rounds in a 10 round mag. The larger mags don't allow much more capacity because the magazine starts to swell.
The Valkyrie is a reloader only caliber for now. The case forming requires neck turning and reaming, neck thickness needs to be .014 - .012. As stated 6.5x47 lapua brass is the best brass to make the cases from. It forms the easiest, lasts the longest, is small primer and handles the pressures the best. Also there is zero loss rate when forming.
6.5 Creedmoor cases also work but the brass is softer and only lasts 2-4 firings on average. It also has a loss rate of 10% when forming from creases/folds in the neck/shoulder area. it does have the highest case capacity. Winchester 308 brass also works but you still have a 10% loss rate when forming.
There will be 3 or 4 guys offering brass conversion for the 7 VAR, 270AR and the 257 Bobcat. Already processed brass will also be available in a limited capacity to start.
Dies will be from Whidden gunworks with their competition micrometer seater die which is one of the best in the industry.
Barrels will be made by X-Caliber with choices of
5R:7, 1:8, 5R:8, 1:9 twist rates along with your choice of profile and fluting if wanted. We have been testing the 5r:8 and 1:9 and both are working excellent.
Some of the powders that work well with the Valkyrie are: Leverevolution,CFE 223, xbr 8208, H335,Benchmark, AA2520, TAC, AA2230 and Xterminator. Also r15 and arcomp might also work well also n530, n540 should be workable powders. imr 4166, h4895, imr 4895 will also work but velocities are down from lever and cfe but they have very good accuracy.