Finally got the NXS 5.5x22x56 MOAR, zero-stop installed on my new 7mag built by Dave Bruno. Loaded some "break-in" loads while increasing powder charge. First time to shoot this rifle was today.
Jewel trigger 1 pound
26” Krieger SS barrel 9 twist
Stiller Predator action
168 Berger hunting VLD seated 0.010 off the lands, new Winchester brass, Federal 215M primers. I sent the sizer die back to manufacturer to hone neck 0.003 smaller than loaded dummy round. I resize all new brass with expander button, then again without to reduce runout. I lube inside neck with “Froggy’s” lube (graphite suspended in alcohol), prior to seating bullets for ease of release but good neck tension.
Took the rifle out today for first session. Barrel break-in is arguable as to its necessity. I do it because it makes me feel warm and fuzzy. Shots 1-5 were test rounds for max charge of Hodgdon Retumbo. Shots 6-8 were 72 grains, which produced a 1/2" group, then shots 9-11 are pictured above.
I shot and cleaned after each of the first 5 but could see no trace of copper through the muzzle in the sunlight after any shot. Then I’d shoot the 3 shot groups and clean. Barrel allowed to cool between each shot and group.
This is the first case I’ve ever run into when the barrel, NEW, was basically already “broken-in.” It simply didn’t copper foul from the muzzle view. Will retest loads at range Thursday but this, for now, is my working load for Colorado next month. This 3 shot group measures just under 1/4 minute.
Took the new 6.5-284 out today also with 140 Berger VLDs and H4831SC, same process. No groups were over 1" but it fouled pretty bad but was easy to clean. It has a Bartlein bbl. The H4831SC load is promising as there was no vert/horiz stringing.
I still need to add powder to find max load. Will have time Thursday to play with it as well.
Then I have a brand new 280 build and another 270 Win (best caliber on earth) to play with next week. 280 has a Shilen, the 270 has a Krieger. Both have Stiller TAC 300 actions and McM Edge stocks.
2 of the 4 rifles are going to CO next month on my mule deer hunt. The 7mag is one for sure.