Dimitri,
Thats the "standardised" velocity that I talked about before,
My calculations are based on a few assumptions:
1. the fact that the velocity of my projectiles are the same (at least at the muzzle) 1100 fps.
2. The assumption that to get to the 250mters distance, the projectile will take about 0.75 seconds give or take 0.03 s, depending on the ballistic coefficient.
3. Based on the two above, for ballistic coeff of between 0.2 to 0.5, the projectile drop differs to a maximum of about 10 inches. (I got this figure from the PointBlank software)

So, based on assumption No.3, I thought that if I get the velocity to about the same (1100 fps) I should be able to shoot at the aiming point for all my different calibers to a distance of about 250 meters (that is if the target area is larger than 10 inches) otherwise, I only have to make very slight correction for my higher BC projectiles.

Grr... now I am confused.

Phil,

Sorry my physics is rusty, but you are correct.

Dimitri

Bushmaster wrote:

Heck Hunterjoe21...In the mountains where I'm from, anything over 35 yards was a long shot. Most of the deer and elk I've shot in the Northwest were under 35 yards. I took one elk at 60 yards. I even took an 8 point Blacktail (eastern count) at 4 yards once...Where I'm at now, here in the Ozarks, I might have a 100 yard (FF) shot. The longest shot I have ever had was just barely under 200 yards... Those in places like Montana, Wyoming, Utah, Texas, etc will definately have the longest shots to make...

LOL Bushy

The first five seasons I hunted when I was a kid (before rifled, cantlivered, scoped shotguns were the norm) it was considered poor woodsmanship to attempt a shot longer than 50 yards.

A quote from Grandpops when I was young "If you aint close enough to see eyelashes, you aint close enough to shoot"

Dimitri wrote:

Phil, Sorry my physics is rusty, but you are correct. Dimitri

Heh, heh. I love that stuff. When I found my copy of Hatcher's, I read it from cover to cover in 3 days. It has helped my shooting in many ways.

FALPhil wrote:

Dimitri wrote: Cause everything drops at a rate of 9.80665m/s or 32.1740ft/s or 386.088in/s (more or less). Actually, gravity is a acceleration proposition, so the rate is 9.8m/s/s or 32 ft/s/s. The formulae get complicated, but a good study is Hatcher's Notebook.

Have a look at this link Phil. Just for info mate. It appears 'Mitri's figure may be correct.

Errata Hatchers Notebook

Cheers, Vince

Vince,

I wasn't commenting on the figures; my comment was on the unit of measurement.

Gravitational forces cause acceleration, not velocity. But, the figures are just statistical means. Gravitational pull is not the same in the Kasmir as it is in Death Valley.

Here is another interesting site on the subject:
www.daviddarling.info/...cgrav.html

I had seen that errata sheet on rec.guns many years ago and had forgotten about it. Thanks for reminding me - I am going to bookmark it.

An excellent book on ballistics is "Understanding Firearm Ballistics" by Robert A. Rinker. It covers internal, external and terminal ballistics in a pretty understandable format. If you really want to dig into the math it has that too.

Pumpkinslinger wrote:

An excellent book on ballistics is "Understanding Firearm Ballistics" by Robert A. Rinker. It covers internal, external and terminal ballistics in a pretty understandable format. If you really want to dig into the math it has that too.

I have that book too. It is indeed a good book.

Vince,

The numbers I used were more specific but I didn't square the "time" part of them which is what Phil pointed out.

Dimitri

I use the time tested W.A.G. method. It was good enough for Carlos Hathcock & my Father, Its good enough for me.

Oh, W.A.G. is "Wild A$$ Guess"!! I dont need no fancy book or lazer range finder.

Crackshot wrote:

I use the time tested W.A.G. method. It was good enough for Carlos Hathcock & my Father, Its good enough for me. Oh, W.A.G. is "Wild A$$ Guess"!! I dont need no fancy book or lazer range finder.

Cracks thats what I want to learn.. W.A.G. method

Crackshot wrote:

I use the time tested W.A.G. method. It was good enough for Carlos Hathcock & my Father, Its good enough for me. Oh, W.A.G. is "Wild A$$ Guess"!! I dont need no fancy book or lazer range finder.

GySgt Hathcock didn't use a whole lot of WAG. His longest shot on record was measured before he took it - it was a setup on a known enemy route.

The USMC standard issue sniper scope of the Vietnam era was the Redfield 3-9x with Accu Range on top of a custom Rem 700 in 308 and known as the M40. [Note: Some marines I have spoken with about their service in Vietnam told me that the earliest shipments of M40s were in 30-06, but thay may have been confusing the M40 with the previous issue Winchester Model 70, which was only issued in 30-06] I don't know if he was issued one of the Redfields because there were several scopes available, and some were even mailed from home by relatives. But, the original scoped M40 was delivered in late '66, about the time Sgt Hathcock deployed to SE Asia. IIRC, he redeployed for a second tour in '68, but it was cut short due to his being blown off a transport that ran over a mine.

While his two more famous shots occurred when he operated solo, he mostly worked with a spotter who helped him with ranges. He was a very humble man, by all accounts.

The Accu Range and Accu Trac offerings from the original Redfield in Denver are my favorite scopes because of their accurate ranging capabilities.

Like yours, my dad was a phenomenal shot. But he never took a shot he knew he couldn't make, which made him look all the better. My problem is that I am willing to try, even when I have doubts.

hunterjoe21 wrote:

Bushmaster wrote: Heck Hunterjoe21...In the mountains where I'm from, anything over 35 yards was a long shot. Most of the deer and elk I've shot in the Northwest were under 35 yards. I took one elk at 60 yards. I even took an 8 point Blacktail (eastern count) at 4 yards once...Where I'm at now, here in the Ozarks, I might have a 100 yard (FF) shot. The longest shot I have ever had was just barely under 200 yards... Those in places like Montana, Wyoming, Utah, Texas, etc will definately have the longest shots to make... LOL Bushy The first five seasons I hunted when I was a kid (before rifled, cantlivered, scoped shotguns were the norm) it was considered poor woodsmanship to attempt a shot longer than 50 yards. A quote from Grandpops when I was young "If you aint close enough to see eyelashes, you aint close enough to shoot"

Your grandpops didn't hunt in the mountains of CO or on the flat plains of the prairie.

skb2706 wrote:

hunterjoe21 wrote: Bushmaster wrote: Heck Hunterjoe21...In the mountains where I'm from, anything over 35 yards was a long shot. Most of the deer and elk I've shot in the Northwest were under 35 yards. I took one elk at 60 yards. I even took an 8 point Blacktail (eastern count) at 4 yards once...Where I'm at now, here in the Ozarks, I might have a 100 yard (FF) shot. The longest shot I have ever had was just barely under 200 yards... Those in places like Montana, Wyoming, Utah, Texas, etc will definately have the longest shots to make... LOL Bushy The first five seasons I hunted when I was a kid (before rifled, cantlivered, scoped shotguns were the norm) it was considered poor woodsmanship to attempt a shot longer than 50 yards. A quote from Grandpops when I was young "If you aint close enough to see eyelashes, you aint close enough to shoot" Your grandpops didn't hunt in the mountains of CO or on the flat plains of the prairie.

No he didn't, I hunted the heavy woods in Southeastern Ohio with him when I was a kid with smoothbore shotguns and Foster style slugs. Rifled shotgun barrels didn't exist, and a brass bead was your sighting system (if you had a "fancy" shotgun you had 2 beads), and most people I knew didn't even have replaceable choke tubes.

Knowing your game animal, and how big it is helps a great deal in the W.A.G. system. If you know the average dimensions of your target that in itself can give strong clues to its distance.
Some folks use small deer pictures and air rifles to practise for deer season.