Forums
New posts
Search forums
What's new
Articles
Latest reviews
Author list
Classifieds
Log in
Register
What's new
Search
Search
Search titles and first posts only
Search titles only
By:
New posts
Search forums
Menu
Log in
Register
Install the app
Install
Forums
Rifles, Reloading, Optics, Equipment
Rifles, Bullets, Barrels & Ballistics
Berger .338 300 grain EH - ballistic coefficient
JavaScript is disabled. For a better experience, please enable JavaScript in your browser before proceeding.
You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an
alternative browser
.
Reply to thread
Message
<blockquote data-quote="Timber338" data-source="post: 1172100" data-attributes="member: 33822"><p>Hey guys, thanks for the responses... this is exactly what I was looking for... you are all saying the same thing that the BC should be accurate so look elsewhere.</p><p> </p><p>Doc, thanks for the accurate list of things to look for. Below is the answers to your questions. I was using the Shooter App to calculate all of my drops. I am shooting this bullet using 93 grains of RL33 and seated to a .010" jump. Not sure of my COAL to the tip of the bullet because I always use a comparator, but I think it is right around 4 inches.</p><p></p><p>1: I checked my MV several times in previous days, but not during the day I shot at 1000 yards. The temperature was luckily the same as my most recent Magnetospeed V3 data of 34 degF.</p><p></p><p>2. I'm shooting a 27" Hart barrel with 1:10 twist. Shooter app calculates the stability wtih the exact temp and pressure at 1.86. I believe stability says I should be getting the max .417 BC.</p><p></p><p>3. I have thoroughly tested out my scope and it does have error which I do have a correction factor entered into Shooter. My CF = .97087</p><p></p><p>4. I am using the Shooter app, and I did not account for Coriolis or Aerodynamic jump (is this just spin drift?). Although, I was shooting nearly due north... 8 degrees to be exact. Even if I turn on Coriolis Jump and Spin Drift, Shooter only changes my vertical impact due to Coriolis by 0.4 inches up (higher).</p><p></p><p>In fact, my Kestrel measured 4 mph wind at 250 degrees (left to right). without Coriolis or spin drift turned on, Shooter said to dial 1.5 MOA (15.7 inches) for windage, and my group only impacted about 1.5 inches left. When I turn on spin drift and coriolis, Shooter says to increase my windage correction to 2.2 MOA (22.8 inches). If I had adjusted for that I would have shot very far left. And wind flags at 1000 appeared to have about the same effect from wind as the flags right next to me. Not sure how to interpret that data point. Also, I verified pressure to be 25.30 with both my Kestrel and my Leica 1600b.</p><p></p><p>5. I am as close as i can tell on scope height ... but you say " bore height at the turrets" ... should I be measuring my scope height to something other than the center of the optic? Or am I just totally missing something here?</p><p></p><p>6. Great article, thanks for the link. It seems Brain's book on ballistics would be a worth while investment.</p><p></p><p>7. I am not pointing my bullets, and because my goal is to hunt with these bullets, I believe pointing would be a very bad idea.... correct?</p><p></p><p>So based on everything here especially your experience with this 300 grain Elite Hunter B.C., it sounds like you would recommend adjusting MV rather than B.C. in my application ??</p><p></p><p>If I drop my MV down to 2705 it brings me right up to where I need to be. I will certainly get more data points shooting at long range. I'm not sure what I will see at shorter distances like 600 yards that won't be easier to see at 1000 or further. I don't have any way to calibrate my Magnetospeed, but it has proven to be very very close to perfect for my 215 berger hybrid out of my 300 win mag. Would be easier for me to accept adjusting MV if that bullet were also impacting similarly low.</p></blockquote><p></p>
[QUOTE="Timber338, post: 1172100, member: 33822"] Hey guys, thanks for the responses... this is exactly what I was looking for... you are all saying the same thing that the BC should be accurate so look elsewhere. Doc, thanks for the accurate list of things to look for. Below is the answers to your questions. I was using the Shooter App to calculate all of my drops. I am shooting this bullet using 93 grains of RL33 and seated to a .010" jump. Not sure of my COAL to the tip of the bullet because I always use a comparator, but I think it is right around 4 inches. 1: I checked my MV several times in previous days, but not during the day I shot at 1000 yards. The temperature was luckily the same as my most recent Magnetospeed V3 data of 34 degF. 2. I'm shooting a 27" Hart barrel with 1:10 twist. Shooter app calculates the stability wtih the exact temp and pressure at 1.86. I believe stability says I should be getting the max .417 BC. 3. I have thoroughly tested out my scope and it does have error which I do have a correction factor entered into Shooter. My CF = .97087 4. I am using the Shooter app, and I did not account for Coriolis or Aerodynamic jump (is this just spin drift?). Although, I was shooting nearly due north... 8 degrees to be exact. Even if I turn on Coriolis Jump and Spin Drift, Shooter only changes my vertical impact due to Coriolis by 0.4 inches up (higher). In fact, my Kestrel measured 4 mph wind at 250 degrees (left to right). without Coriolis or spin drift turned on, Shooter said to dial 1.5 MOA (15.7 inches) for windage, and my group only impacted about 1.5 inches left. When I turn on spin drift and coriolis, Shooter says to increase my windage correction to 2.2 MOA (22.8 inches). If I had adjusted for that I would have shot very far left. And wind flags at 1000 appeared to have about the same effect from wind as the flags right next to me. Not sure how to interpret that data point. Also, I verified pressure to be 25.30 with both my Kestrel and my Leica 1600b. 5. I am as close as i can tell on scope height ... but you say " bore height at the turrets" ... should I be measuring my scope height to something other than the center of the optic? Or am I just totally missing something here? 6. Great article, thanks for the link. It seems Brain's book on ballistics would be a worth while investment. 7. I am not pointing my bullets, and because my goal is to hunt with these bullets, I believe pointing would be a very bad idea.... correct? So based on everything here especially your experience with this 300 grain Elite Hunter B.C., it sounds like you would recommend adjusting MV rather than B.C. in my application ?? If I drop my MV down to 2705 it brings me right up to where I need to be. I will certainly get more data points shooting at long range. I'm not sure what I will see at shorter distances like 600 yards that won't be easier to see at 1000 or further. I don't have any way to calibrate my Magnetospeed, but it has proven to be very very close to perfect for my 215 berger hybrid out of my 300 win mag. Would be easier for me to accept adjusting MV if that bullet were also impacting similarly low. [/QUOTE]
Insert quotes…
Verification
Post reply
Forums
Rifles, Reloading, Optics, Equipment
Rifles, Bullets, Barrels & Ballistics
Berger .338 300 grain EH - ballistic coefficient
Top