338LM Bullet Stability - 300gr SMK in 11 twist
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Re: 338LM Bullet Stability - 300gr SMK in 11 twist
A buddy shoots the 300's out of his TRG and they are 12 twist, so 11 should be plenty.
A buddy shoots the 300's out of his TRG and they are 12 twist, so 11 should be plenty.
Re: 338LM Bullet Stability - 300gr SMK in 11 twist
they took care of your first question, now to answer your next question, yet it will still be stable when crossing the transonic barrier and subsonic
they took care of your first question, now to answer your next question, yet it will still be stable when crossing the transonic barrier and subsonic
Re: 338LM Bullet Stability - 300gr SMK in 11 twist
This is contradictory to my findings. Regardless of charge.
I would stick to the 250grs.
You will get yaw or key-hole-ing (not end over end) type paper punches that are oblong with the heavy bullet and the slow twist.
Seating off lands matters as well.
1:10 or 1:9 for 300or 300+...
This is contradictory to my findings. Regardless of charge.
I would stick to the 250grs.
You will get yaw or key-hole-ing (not end over end) type paper punches that are oblong with the heavy bullet and the slow twist.
Seating off lands matters as well.
1:10 or 1:9 for 300or 300+...
Re: 338LM Bullet Stability - 300gr SMK in 11 twist
i am using an AWSM with the original barrel. i keep my COAL at 3.6 to be able to feed from the magazine. unless i replace the barrel with a custom chamber, i may be far from the lands. is the 300 SMK a VLD?
my load using H1000 drives the bullet at 2800 fps with ES=12.3, yet my groups suck (about 2" at 100 yards). what am i doing wrong?
i am using an AWSM with the original barrel. i keep my COAL at 3.6 to be able to feed from the magazine. unless i replace the barrel with a custom chamber, i may be far from the lands. is the 300 SMK a VLD?
my load using H1000 drives the bullet at 2800 fps with ES=12.3, yet my groups suck (about 2" at 100 yards). what am i doing wrong?
Re: 338LM Bullet Stability - 300gr SMK in 11 twist
Just so you know you have many more variables than just what we are talking about... What is your hole like in your target? What is your group size at 200?
Just so you know you have many more variables than just what we are talking about... What is your hole like in your target? What is your group size at 200?
Re: 338LM Bullet Stability - 300gr SMK in 11 twist
the holes at both 100 and 200 yards are perfectly round. the groups at 200 yards are larger. this is dismal. so much so i have not kept any targets.
i have made sure to eliminate parallax.
i will try a different scope (scope currently mounted is USO TPAL 5-25X).
the trigger pull is heavier than i like. i will have to find the information on lightening the first stage.
i am wondering if the recoil is causing me to flinch.
any ideas?
the holes at both 100 and 200 yards are perfectly round. the groups at 200 yards are larger. this is dismal. so much so i have not kept any targets.
i have made sure to eliminate parallax.
i will try a different scope (scope currently mounted is USO TPAL 5-25X).
the trigger pull is heavier than i like. i will have to find the information on lightening the first stage.
i am wondering if the recoil is causing me to flinch.
any ideas?
Re: 338LM Bullet Stability - 300gr SMK in 11 twist
No trouble here-
300 smk, 11 twist, 3300 fps, scary accurate and easy to shoot.
No trouble here-
300 smk, 11 twist, 3300 fps, scary accurate and easy to shoot.
Re: 338LM Bullet Stability - 300gr SMK in 11 twist
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: elkregulator</div><div class="ubbcode-body">No trouble here-
300 smk, 11 twist, 3300 fps, scary accurate and easy to shoot. </div></div>
that's nice. getting back to reality, i was talking about the 338LM.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: elkregulator</div><div class="ubbcode-body">No trouble here-
300 smk, 11 twist, 3300 fps, scary accurate and easy to shoot. </div></div>
that's nice. getting back to reality, i was talking about the 338LM.
Re: 338LM Bullet Stability - 300gr SMK in 11 twist
My first sub 1/2 MOA 5 shot groups fired with a 338 Lapua using a 11.25 twist & 300 SMK. I never had the chance to shoot farther than 1,000 yards. However 11.25 twist works just fine with 300 SMK out to 1,000 yards.
Semper Fi
My first sub 1/2 MOA 5 shot groups fired with a 338 Lapua using a 11.25 twist & 300 SMK. I never had the chance to shoot farther than 1,000 yards. However 11.25 twist works just fine with 300 SMK out to 1,000 yards.
Semper Fi
Re: 338LM Bullet Stability - 300gr SMK in 11 twist
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 95LTZ</div><div class="ubbcode-body">My first sub 1/2 MOA 5 shot groups fired with a 338 Lapua using a 11.25 twist & 300 SMK. I never had the chance to shoot farther than 1,000 yards. However 11.25 twist works just fine with 300 SMK out to 1,000 yards.
Semper Fi
</div></div>
what velocity are you driving the 300 SMK at?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 95LTZ</div><div class="ubbcode-body">My first sub 1/2 MOA 5 shot groups fired with a 338 Lapua using a 11.25 twist & 300 SMK. I never had the chance to shoot farther than 1,000 yards. However 11.25 twist works just fine with 300 SMK out to 1,000 yards.
Semper Fi
</div></div>
what velocity are you driving the 300 SMK at?
Re: 338LM Bullet Stability - 300gr SMK in 11 twist
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: penumbra</div><div class="ubbcode-body">the holes at both 100 and 200 yards are perfectly round. the groups at 200 yards are larger. this is dismal. so much so i have not kept any targets.
i have made sure to eliminate parallax.
i will try a different scope (scope currently mounted is USO TPAL 5-25X).
the trigger pull is heavier than i like. i will have to find the information on lightening the first stage.
i am wondering if the recoil is causing me to flinch.
any ideas? </div></div>
Another Variable taken out of the equation (as usually the groups get tighter at 200and out than 100), also since the holes are round another variable taken out of the equation.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: penumbra</div><div class="ubbcode-body">the holes at both 100 and 200 yards are perfectly round. the groups at 200 yards are larger. this is dismal. so much so i have not kept any targets.
i have made sure to eliminate parallax.
i will try a different scope (scope currently mounted is USO TPAL 5-25X).
the trigger pull is heavier than i like. i will have to find the information on lightening the first stage.
i am wondering if the recoil is causing me to flinch.
any ideas? </div></div>
Another Variable taken out of the equation (as usually the groups get tighter at 200and out than 100), also since the holes are round another variable taken out of the equation.
Re: 338LM Bullet Stability - 300gr SMK in 11 twist
I'll have to check & see if I still have the chrono sheets.
Semper Fi
I'll have to check & see if I still have the chrono sheets.
Semper Fi
Re: 338LM Bullet Stability - 300gr SMK in 11 twist
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: elkregulator</div><div class="ubbcode-body">No trouble here-
300 smk, 11 twist, 3300 fps, scary accurate and easy to shoot. </div></div>
Is that a correct MV? at 3300 fps? for standard 338LM caliber?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: elkregulator</div><div class="ubbcode-body">No trouble here-
300 smk, 11 twist, 3300 fps, scary accurate and easy to shoot. </div></div>
Is that a correct MV? at 3300 fps? for standard 338LM caliber?
Re: 338LM Bullet Stability - 300gr SMK in 11 twist
No, sorry I didn't read the question correctly... That is not in a LM. However, I am shooting a 300 smk in a 11 twist without problems.
No, sorry I didn't read the question correctly... That is not in a LM. However, I am shooting a 300 smk in a 11 twist without problems.
Re: 338LM Bullet Stability - 300gr SMK in 11 twist
Probably the most popular twist for .338's shooting the 300's is a 1-10.
Some will say you need a faster twist than even 1-10 to shoot the 300's and maybe you do if you have a slow shooting .338something or other but 1-10 is what the largest percentage are built with.
Probably the most popular twist for .338's shooting the 300's is a 1-10.
Some will say you need a faster twist than even 1-10 to shoot the 300's and maybe you do if you have a slow shooting .338something or other but 1-10 is what the largest percentage are built with.
Re: 338LM Bullet Stability - 300gr SMK in 11 twist
According to the JBM stability program an 11 twist will stabilize the bullet at that velocity. The slower the twist the less pressure build up. But everything i have read is that when the bullet nears transsonic the faster twist is a benefit as well as the bullet type. Sierra's hold up well at transonic speed.
http://www.jbmballistics.com/cgi-bin/jbmstab-5.1.cgi
According to the JBM stability program an 11 twist will stabilize the bullet at that velocity. The slower the twist the less pressure build up. But everything i have read is that when the bullet nears transsonic the faster twist is a benefit as well as the bullet type. Sierra's hold up well at transonic speed.
http://www.jbmballistics.com/cgi-bin/jbmstab-5.1.cgi
Re: 338LM Bullet Stability - 300gr SMK in 11 twist
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: elkregulator</div><div class="ubbcode-body">No, sorry I didn't read the question correctly... That is not in a LM. However, I am shooting a 300 smk in a 11 twist without problems.
</div></div>
velocity affects stability through RPM, but not as much as twist.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: elkregulator</div><div class="ubbcode-body">No, sorry I didn't read the question correctly... That is not in a LM. However, I am shooting a 300 smk in a 11 twist without problems.
</div></div>
velocity affects stability through RPM, but not as much as twist.
Re: 338LM Bullet Stability - 300gr SMK in 11 twist
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: penumbra</div><div class="ubbcode-body">i am using an AWSM with the original barrel. i keep my COAL at 3.6 to be able to feed from the magazine. unless i replace the barrel with a custom chamber, i may be far from the lands. is the 300 SMK a VLD?
my load using H1000 drives the bullet at 2800 fps with ES=12.3, yet my groups suck (about 2" at 100 yards). what am i doing wrong?
</div></div>
Have you checked to see if your cartridges are slamming into the front magazine wall when you fire deforming the nose on the bullet? Easy to check and would certainly explain poor groups.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: penumbra</div><div class="ubbcode-body">i am using an AWSM with the original barrel. i keep my COAL at 3.6 to be able to feed from the magazine. unless i replace the barrel with a custom chamber, i may be far from the lands. is the 300 SMK a VLD?
my load using H1000 drives the bullet at 2800 fps with ES=12.3, yet my groups suck (about 2" at 100 yards). what am i doing wrong?
</div></div>
Have you checked to see if your cartridges are slamming into the front magazine wall when you fire deforming the nose on the bullet? Easy to check and would certainly explain poor groups.
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