I've been shooting and hunting for years, and learn something new all the time. While shooting my Ruger M77 MkII 25-06, using Sierra 90 blitzking at 3570 fps from my 26 inch bbl.. I found out that my drop chart was wayyyyy off. I know paper charts and real life are not the same, but most of the time It has got me close.
I am running low on my 115 Berger bullets and know varmint bullet kill coyotes so much better (dump all of energy into them) I thought I would test the 90's out at 400 and 600 yards.. with a 200 yard zero. my 2.25 inch group at 425 yards was 3 inches right. and about 2 inches lower than the chart.
at 625 yards my group was 9 inches right and a ft lower than what my drop chart said. and also a foot to the right.
I used to regularly shoot water jugs at 500 yards 1st shot using my drop charts.. my errors on paper was either rifle cant (no level) or my shooting error.
although my 115 Bergers shoot well. and hold 1/2 most the time out to long range, I would like to make a true varmint bullet work out to this range.
After some research I found out that bullet that are spun too fast, will not go to sleep and cause problems.
Years ago I used to load my 85 Ballistic tips to 3700 fps... at 300 yards I was getting 4-5 inch groups, but when I backed them down to 3400 fps, they was well under moa.. jackets coming apart? Nope, I've seen this happen when I shoot 110 Vmaxes out of my 300 Winny at 3700 fps, one out of 10 makes it to target at 100 yards. When a jacket comes apart, then they never make it to target.
I came across a few links and it is common if bullets are spun too fast then at long range where a rifle axis of deg is pointed up, the bullet will not nose down like most bullets do.. I think it's called "spherical precession"
What the bullet is doing is NOT nosing down in flight (long range.. the upward pointed bullet is now skidding on the air.. a right twist would make the bullet like a paddle wheel on the air (from rifling marks) spinning at 200,000+ rpm's veering to the right and killing the drag coefficient
Some say that you can not over stabilize a bullets. ??
if you never shoot past 400 yards, then you'll probably never know what this is about. most never shot past 100 yards.
This is opinion vs real life.
REAL life=
Bryan Litz explains this all too well. He is the head engineer of Berger bullets. an champion national shooter, worked for the military on the subject, and an expert in ballistics. Berger Bullets are probably the the most accurate bullets on the face of the Earth for long range shooting.
I said above I learn something new everyday, and yes this can happen. my 2506 is a 10 twist, best for 100-120 grain bullets at around 2900-3200 fps
so a 90 at 3570 (I loaded them down from 3650 fps) fps is too many rpms for the shorter bullets to go sleep.
Bullet stabilizing can sometimes be a balance.
too little spin and bullets tumble (I've experienced this too).. too much spin and bullet never goes to sleep. nose of bullet at long range will still be pointed up while bullet is traveling downward.. and bullet drag BC will suffer greatly.
most people will never experience this because they either have never shot past 500 yards or shot past 500 yards with varmint bullets in a 10 twist.
I can say I Learn something new all the time.
PS I loaded them down to 3400 fps and will test them soon and let you know.
I am running low on my 115 Berger bullets and know varmint bullet kill coyotes so much better (dump all of energy into them) I thought I would test the 90's out at 400 and 600 yards.. with a 200 yard zero. my 2.25 inch group at 425 yards was 3 inches right. and about 2 inches lower than the chart.
at 625 yards my group was 9 inches right and a ft lower than what my drop chart said. and also a foot to the right.
I used to regularly shoot water jugs at 500 yards 1st shot using my drop charts.. my errors on paper was either rifle cant (no level) or my shooting error.
although my 115 Bergers shoot well. and hold 1/2 most the time out to long range, I would like to make a true varmint bullet work out to this range.
After some research I found out that bullet that are spun too fast, will not go to sleep and cause problems.
Years ago I used to load my 85 Ballistic tips to 3700 fps... at 300 yards I was getting 4-5 inch groups, but when I backed them down to 3400 fps, they was well under moa.. jackets coming apart? Nope, I've seen this happen when I shoot 110 Vmaxes out of my 300 Winny at 3700 fps, one out of 10 makes it to target at 100 yards. When a jacket comes apart, then they never make it to target.
I came across a few links and it is common if bullets are spun too fast then at long range where a rifle axis of deg is pointed up, the bullet will not nose down like most bullets do.. I think it's called "spherical precession"
What the bullet is doing is NOT nosing down in flight (long range.. the upward pointed bullet is now skidding on the air.. a right twist would make the bullet like a paddle wheel on the air (from rifling marks) spinning at 200,000+ rpm's veering to the right and killing the drag coefficient
Some say that you can not over stabilize a bullets. ??
if you never shoot past 400 yards, then you'll probably never know what this is about. most never shot past 100 yards.
This is opinion vs real life.
REAL life=
Bryan Litz explains this all too well. He is the head engineer of Berger bullets. an champion national shooter, worked for the military on the subject, and an expert in ballistics. Berger Bullets are probably the the most accurate bullets on the face of the Earth for long range shooting.
I said above I learn something new everyday, and yes this can happen. my 2506 is a 10 twist, best for 100-120 grain bullets at around 2900-3200 fps
so a 90 at 3570 (I loaded them down from 3650 fps) fps is too many rpms for the shorter bullets to go sleep.
Bullet stabilizing can sometimes be a balance.
too little spin and bullets tumble (I've experienced this too).. too much spin and bullet never goes to sleep. nose of bullet at long range will still be pointed up while bullet is traveling downward.. and bullet drag BC will suffer greatly.
most people will never experience this because they either have never shot past 500 yards or shot past 500 yards with varmint bullets in a 10 twist.
I can say I Learn something new all the time.
PS I loaded them down to 3400 fps and will test them soon and let you know.