Some advice here, please

[epoletna]

I'm beginning to reach out with my .270 Winchester. This is not one of those super-modern rifles with a 35" barrel wrapped with carbon fiber and a rare action that it is carved out of unobtainium by virgins working in the light of a full moon. It's a straight out of the box pre-'64 Winchester built in 1954, and I'm enjoying load development with it.

So here's my question, for those of you with sophisticated computer programs that tell you how much elevation and windage to crank in based on distance, wind, Coriolis effect, and phase of the moon: how many inches will a 130 grain Sierra bullet traveling at 3,000 FPS at the muzzle drop from 100 yards to 200 yards?

I know this is not a sophisticated equation. I am getting decent groups at 100 yards with my current load, and I want to begin shooting at 200 yards, but don't want to fire a 200 yard group to determine how many inches I need to come up, and I know there are computer programs that will tell a shooter how many clicks to crank in.

So what say you? How many inches should I crank in for a 130 grain Sierra soft point boat tail bullet that leaves the muzzle at 3000 FPS, if I want to hit the bullseye at 200 yards too? This should be a pretty straightforward computation, I should think.

If I'm successful at this, I hope eventually to reach out to 500 yards. Small potatoes, I know, but there you are.

Thanks.

 

[P7M13]

270 Win Ballistics Chart & Coefficient GunData.org

The following ins a 500 yd 270 Win ballistic trajectory and drop chart that follows a 130gr Winchester Silvertip with a ballistic coeddicient of .337 from the time it exits the muzzle until it hits the 500 yard mark.

gundata.org

You can also customize the chart inputs

 

[epoletna]

Three inches. Thank you very much. I was going to try 2.5 inches, but 3 sounds pretty reasonable. I appreciate the help.

 

[DJ Fergus]

If you are just wanting to shoot to 200 yards with it, set it for 1.5 inches high from dead center bullseye @ 100 yards and leave it there. This should get you really close to center of bullseye at 200. Just put the cross hairs on the vitals (lung/heart area) of deer sized game that are 200 yards & closer and pull the trigger. Your center of three shot groups should never be much more than 1.5" high or low on a shot in between 0 to 200 yards.

 

[NDF]

Inches high @ 100 yds to 500 yds, 130gr @ 3000fps
200 + 1.2
300 + 2.9
400 + 4.7
500 + 6.5

 

[nmbarta]

How accurate is your rifle?
How big is your bullseye?
Impossible questions to answer without more information.

 

[LVJ76]

Ballistics apps are pretty cool for us that grew up shooting at longer distances using the Kentucky windage method.

Most rifle cartridges sighted at 100 yds, will drop from 1" to 2" at 200 yds and 6" to 8" at 300 yds, yours with a 130gr bullet will shoot pretty flat. My 7mm Rem Mag I sight at it at 250 instead of 100, so I only have a drop of say 4" at 300 and I'm only 3" hight at 100. So I have whats called a point blank range up to 300, meaning I can take a shot at vitals and be dead on. It's good to be set up like this when you jave to take a quick shot at these ranges.

I shoot Silhouette competition and used to set up dial up charts so I knew exactky how many clicks I neede to shoot at 500m with a 200m cero. With apps now you just look at the app and dial up. No need to set up a chart in advance anymore.

Now charts are good to have when hunting, no time to look at the app, just look at the chart that accessible when taped to the rifle, dial up and shoot. Wind is a little different, that you need to learn how to read and then adjust as needed.

Yes there is a little more to all this but this is the short version.

Hope this helps and stay safe

 

[LVJ76]

Here is an example, it will vary with your altitude, temperature, etc.

 

[Buckys]

I'm using this info on the Sierra bullets but MV=3000:

www.federalpremium.com › premium-centerfire-rifle​

Bullet Weight, 130. Bullet Style, Sierra GameKing Boat-Tail Soft Point. Muzzle Velocity, 3060. Ballistic Coefficient .436. Bullet Length In, 1.125in. / 28.58mm.​

(my work laptop gets left coast internet filtering which prevents access of ~80% web sites that are related to shooting, archery, knives, etc. ... so the calculator that I use is one of the few that does not get filtered and seems to work pretty well)

ShootersCalculator.com | Ballistic Trajectory Calculator

Calculates the ballistic trajectory of a bullet fired from a rifle, handgun or other firearm. Produces a ballistic trajectory chart and table that shows the drop, velocity, kinetic energy, windage, and trajectory of a bullet.

www.shooterscalculator.com

This let's me create a link for the calculations that I ran below in case you want to play with them.
http://www.shooterscalculator.com/ballistic-trajectory-chart.php?t=d671fd58

 

[epoletna]

Thanks, everyone! That is exactly what I was looking for, and what I knew this community could supply.

 

[73driver]

Fascinating post. Do you have a scope that you can easily and reliably dial up and down? What kind of groups are you getting at 100 yards? Are you just plinking or hunting? Your post tickled my curiosity, you are old school using old rifle and not wanting to by a ballistic app for your phone and kinda getting sarcastic about what some put into a new build yet you want to get sophisticated about wanting dial ups for eventually out to 500 yards. Not looking to raz you, just curious if you want to get serious or just see what that 50's MOD 70 will do.

 

[epoletna]

73driver:

I'm pretty serious about serious shooting -- I shoot (and win) mini-palma with 22 RF at 100 yards, and 300 yard BR with a .30 BR and a 6 PPC. But I love the look of the pre-64 Model 70 and I had never shot a .270 until two months ago, when someone offered one locally at a fair price. So I bought it and began trying to see what it would do.

I'm not using a serious scope -- it's more of a target scope I had hanging around. But I can dial it up and down reliably.

To my surprise, the rifle does moderately well off the bench with no special tuning. I'm getting sub MOA at 100 yards (barely), but now I need to stretch that out a little to really see if it will shoot. So I'm going to try moving it out in increments to see how it does. At my age, I doubt I'll ever go elk hunting again, but its fun to dream.

I didn't want to use trial and error to find out how much to dial in at each range, and so I posted my request. Sure enough, I got exactly the advice I was looking for. Now to go to the range and see if I can keep it under one MOA.

I'd still like to find a pre-64 (preferably in the 1954-1955 range) model 70 in .257 Roberts, as a friend shoots that caliber (not in Model 70) and says it has less recoil, but those are getting pretty pricey. So I shoot what I have and see if I can develop a decent load and get any better.

 

[73driver]

73driver:

I'm pretty serious about serious shooting -- I shoot (and win) mini-palma with 22 RF at 100 yards, and 300 yard BR with a .30 BR and a 6 PPC. But I love the look of the pre-64 Model 70 and I had never shot a .270 until two months ago, when someone offered one locally at a fair price. So I bought it and began trying to see what it would do.

I'm not using a serious scope -- it's more of a target scope I had hanging around. But I can dial it up and down reliably.

To my surprise, the rifle does moderately well off the bench with no special tuning. I'm getting sub MOA at 100 yards (barely), but now I need to stretch that out a little to really see if it will shoot. So I'm going to try moving it out in increments to see how it does. At my age, I doubt I'll ever go elk hunting again, but its fun to dream.

I didn't want to use trial and error to find out how much to dial in at each range, and so I posted my request. Sure enough, I got exactly the advice I was looking for. Now to go to the range and see if I can keep it under one MOA.

I'd still like to find a pre-64 (preferably in the 1954-1955 range) model 70 in .257 Roberts, as a friend shoots that caliber (not in Model 70) and says it has less recoil, but those are getting pretty pricey. So I shoot what I have and see if I can develop a decent load and get any better.

Sounds like fun. I love MOD 70's but all mine are newer Classic actions. My first long range custom built rifle was 270 win. I started with 140 gr Bergers and H4831SC and in a short time had it shooting groups I could cover with a dime. I shot some F-Class and PRS matches with it and decided just a bit to much recoil to be shooting 60-80 rounds a match. Good luck.

 

[bullet man]

I've got a Remington adl I shoot 1.5 inches high at 100 yards and I'm good to 300 yrds.