I just got back from sighting in my Remington 700 223 Tactical. It's got a 1/9 twist. Got it sighted in at 100 w/ 75 gr Hornady V-Max and it's about 3/4" consistently at 100 yds. I then shor 2 different Hornady 75 gr factory loads w/ excellent results. 75 gr TAP HP printed between 1" and 3/4" groups, but the Hornady Match BTHP 75 gr ammo blew me away. I got a 5 shot group that was a tad under 1/2 at 100 yds. 4 shots in the same hole and 1 just outside, other groups w/ the Match ammo were all around 3/4" or tighter. Anyone else have good results with 75 gr ammo in a 1/9" barrel? I assume that since I got excellent groups at 100 that they should have similar groups at 200 and 300? Do they have a tendency to spread out after a greater distance due to the lack of faster twist or is it fair to say that since they printed so tight at 100 that they will remain stabil and produce tight groups at 200-600 yds? Thanks Billy
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Re: 1/9 twist and 75 gr accuracy?
Thanks for the report.
I have a 16" upper in 1/9 and was thinking about using the 75`s.
Which powder do you use?
Thanks for the report.
I have a 16" upper in 1/9 and was thinking about using the 75`s.
Which powder do you use?
Re: 1/9 twist and 75 gr accuracy?
Billy,
Really the only way to tell what the bullet is going to do at 2,3,4,500yd is to get out and sling the little bastards down range.
That being said, it is generally true that if you're printing good groups at 100, and you don't have velocity extremes on the high and low side of mean that you're g2g out at distance. High extreme spread will give you varying results like vertical strings.
hope that helps.
C_K
Billy,
Really the only way to tell what the bullet is going to do at 2,3,4,500yd is to get out and sling the little bastards down range.
That being said, it is generally true that if you're printing good groups at 100, and you don't have velocity extremes on the high and low side of mean that you're g2g out at distance. High extreme spread will give you varying results like vertical strings.
hope that helps.
C_K
Re: 1/9 twist and 75 gr accuracy?
I shoot 75gr. Hornaday bthp's in my 16" 1-9 ar. and Hornaday Amax's in my 1-9 .223 Ackley Both shoot great. I run varget behind both.
I shoot 75gr. Hornaday bthp's in my 16" 1-9 ar. and Hornaday Amax's in my 1-9 .223 Ackley Both shoot great. I run varget behind both.
Re: 1/9 twist and 75 gr accuracy?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Billy Jack</div><div class="ubbcode-body"> I assume that since I got excellent groups at 100 that they should have similar groups at 200 and 300? Do they have a tendency to spread out after a greater distance due to the lack of faster twist or is it fair to say that since they printed so tight at 100 that they will remain stabil and produce tight groups at 200-600 yds? Thanks Billy </div></div>
They have a tendency to spread out at greater distance (i.e. unlikely to hold 3/4 moa at 600), but this is NOT from the twist. A bullet becomes MORE stable as its forward velocity slows faster than its rotational velocity. This is where the term "the bullet falls asleep" comes from. I have observed this with longer 80 grain AMaxs - they are only average 1moa bullet at 100, but they hold that 1 moa at 600 whereas other bullets (i.e. SMK) that are sub moa at 100 spread out to 1.5+ moa at 600. The factors that will cause your bullet to open up at longer range include wind (most important), ES of muzzle velocities, differences in the BC from one 75gr to the next, etc. Long-range dispersion is more a factor of time than it is distance - and because the bullet is slower going from 500 to 600 yds than it was going from 0 to 100, the dispersion is going to be greater.
Sorry if I didn't explain this well, but it is some of the more complex ballistics.
In theory, a 9twist barrel should shot a 75gr H with good stability at most MVs, so don't worry about your twist and accuracy - worry more about the wind!
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Billy Jack</div><div class="ubbcode-body"> I assume that since I got excellent groups at 100 that they should have similar groups at 200 and 300? Do they have a tendency to spread out after a greater distance due to the lack of faster twist or is it fair to say that since they printed so tight at 100 that they will remain stabil and produce tight groups at 200-600 yds? Thanks Billy </div></div>
They have a tendency to spread out at greater distance (i.e. unlikely to hold 3/4 moa at 600), but this is NOT from the twist. A bullet becomes MORE stable as its forward velocity slows faster than its rotational velocity. This is where the term "the bullet falls asleep" comes from. I have observed this with longer 80 grain AMaxs - they are only average 1moa bullet at 100, but they hold that 1 moa at 600 whereas other bullets (i.e. SMK) that are sub moa at 100 spread out to 1.5+ moa at 600. The factors that will cause your bullet to open up at longer range include wind (most important), ES of muzzle velocities, differences in the BC from one 75gr to the next, etc. Long-range dispersion is more a factor of time than it is distance - and because the bullet is slower going from 500 to 600 yds than it was going from 0 to 100, the dispersion is going to be greater.
Sorry if I didn't explain this well, but it is some of the more complex ballistics.
In theory, a 9twist barrel should shot a 75gr H with good stability at most MVs, so don't worry about your twist and accuracy - worry more about the wind!
Re: 1/9 twist and 75 gr accuracy?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: JamesBailey</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Billy Jack</div><div class="ubbcode-body"> I assume that since I got excellent groups at 100 that they should have similar groups at 200 and 300? Do they have a tendency to spread out after a greater distance due to the lack of faster twist or is it fair to say that since they printed so tight at 100 that they will remain stabil and produce tight groups at 200-600 yds? Thanks Billy </div></div>
They have a tendency to spread out at greater distance (i.e. unlikely to hold 3/4 moa at 600), but this is NOT from the twist. A bullet becomes MORE stable as its forward velocity slows faster than its rotational velocity. This is where the term "the bullet falls asleep" comes from. I have observed this with longer 80 grain AMaxs - they are only average 1moa bullet at 100, but they hold that 1 moa at 600 whereas other bullets (i.e. SMK) that are sub moa at 100 spread out to 1.5+ moa at 600. The factors that will cause your bullet to open up at longer range include wind (most important), ES of muzzle velocities, differences in the BC from one 75gr to the next, etc. Long-range dispersion is more a factor of time than it is distance - and because the bullet is slower going from 500 to 600 yds than it was going from 0 to 100, the dispersion is going to be greater.
Sorry if I didn't explain this well, but it is some of the more complex ballistics.
In theory, a 9twist barrel should shot a 75gr H with good stability at most MVs, so don't worry about your twist and accuracy - worry more about the wind!
</div></div>
Well put. More complex than I wanted to get...glad you did.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: JamesBailey</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Billy Jack</div><div class="ubbcode-body"> I assume that since I got excellent groups at 100 that they should have similar groups at 200 and 300? Do they have a tendency to spread out after a greater distance due to the lack of faster twist or is it fair to say that since they printed so tight at 100 that they will remain stabil and produce tight groups at 200-600 yds? Thanks Billy </div></div>
They have a tendency to spread out at greater distance (i.e. unlikely to hold 3/4 moa at 600), but this is NOT from the twist. A bullet becomes MORE stable as its forward velocity slows faster than its rotational velocity. This is where the term "the bullet falls asleep" comes from. I have observed this with longer 80 grain AMaxs - they are only average 1moa bullet at 100, but they hold that 1 moa at 600 whereas other bullets (i.e. SMK) that are sub moa at 100 spread out to 1.5+ moa at 600. The factors that will cause your bullet to open up at longer range include wind (most important), ES of muzzle velocities, differences in the BC from one 75gr to the next, etc. Long-range dispersion is more a factor of time than it is distance - and because the bullet is slower going from 500 to 600 yds than it was going from 0 to 100, the dispersion is going to be greater.
Sorry if I didn't explain this well, but it is some of the more complex ballistics.
In theory, a 9twist barrel should shot a 75gr H with good stability at most MVs, so don't worry about your twist and accuracy - worry more about the wind!
</div></div>
Well put. More complex than I wanted to get...glad you did.
Re: 1/9 twist and 75 gr accuracy?
Billy i have the same rifle.I shoot 77smk reloads and have taken it out to 500.I can consistantly hit a 8 in steel plate at that distance.@ 100 it shoots 1/2 moa.I was suprised myself and found out by accident.I can interchange 69 smks with the same results.I have only shot it on paper to 400. I got groups 0f 3 to 3.5 at that distance.Still developing.Hope this helps.1Sg (ret)
Billy i have the same rifle.I shoot 77smk reloads and have taken it out to 500.I can consistantly hit a 8 in steel plate at that distance.@ 100 it shoots 1/2 moa.I was suprised myself and found out by accident.I can interchange 69 smks with the same results.I have only shot it on paper to 400. I got groups 0f 3 to 3.5 at that distance.Still developing.Hope this helps.1Sg (ret)
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