118 rounds CBTO: 2.404"
Adding there has been no more than 3 consecutive shots fired without letting the barrel cool.
Also adding pics of throat, leade and bore.
Freebore:
Leade:
So after 118 rounds of N570 and Berger 195 EOL's the throat, leade and bore look surprisingly nice shape. The load currently is 68.9 grains and a Load CBTO length of 2.410" and a COAL of 3.174". This puts it into the lands around .006" currently. Powder at that charge weight is edging just past the shoulder/neck junction. The load has produced from 0.1 to 0.3 moa and only horizontal dispersion out to 650 yards with groups measuring just over 2" at that distance. Velocity has increased from original average velocity of 2,972 fps to 2,993 fps and holding its accuracy so I have a very wide node to play with.
I believe at this point I am going to cut another chamber exactly as this one to mimic it in a Benchmark 8" twist and 4 groove also in a 26" barrel. I am cutting a barrel for a friend with the same chamber in a 22" and I really think I will be at or just under 2900' with it.
195 reasoning........my 28 nosler throws the 195 at 3,120 fps. 7 saum throws it at 2,993 fps. If I use a 1500 Ft-lbs as a minimum guide that makes my 28 nosler a 1,490 yd rifle and the 7 saum a 1,391 yd rifle. 99 yards of gain!!!!! Doesn't make any sense in using a barrel burning rifle when you can just use a 7 saum and get dang near the same results.
More than likely what is going to happen is I will use this brux as a long range target shooting barrel to play with and the Benchmark for my LRH setup. That away I can used the brass from the Brux in the Benchmark. When I need or want larger I will go with my 30 Nosler.......and yes I will be starting a thread similar using the 245 EOL in a 30 Nosler and a 300 saum comparison if ADG ponies up and makes our Lot of 300 SAUM brass. Fingers crossed.
