Figuring out velocity

[Samdweezel05]

Can I use known bullet data from the manufacturer and data that I collect at the range with a specific bullet to figure out velocity? If all the bullet specs are known, ie. weight and BC, and I have an accurate measurement for bullet drop between lets say 100-200-300yds, can I figure out the muzzle velocity and drop past 300yds? I had a crony once but no longer.

[helotaxi]

As long as the bullet data that you have is accurate and you have eliminated other variables such as shot-to-shot dispersion and so forth, yes; but it won't be nearly as accurate as a measured shot. You would need a center of group measurement for a 10 shot group at each range to eliminate the other variables. Having an accurate BC is vital to this working well at all. Litz measurements would be the preferred source.

[stomp442]

Yep litz data is the way to go for sure. There can be quite the difference between advertised bc's and actual bc's especially if you are shooting a Nosler.

[6mmBR_Shooter]

Stomp, have you found the Noslers to be a higher BC than advertised or lower?

[stomp442]

Way lower than advertised by as much as 12% for some of their bullets. Issue number 81 of the varmint hunter has some very good BC comparison data by litz and the air force academy. I think I made a PDF of the article if your interested I can email it to you. Send me a pm.

[scope eye]

Are you going to be anywhere near exit 22, I have some stuff you can have.

Tanks Dean

[Samdweezel05]

Are you going to be anywhere near exit 22, I have some stuff you can have.

Tanks Dean

What kind of stuff? I like stuff.

[scope eye]

I have bullets and dies, I know I have brass I just cant find it,

Tanks Dean

[Samdweezel05]

I have bullets and dies, I know I have brass I just cant find it,

Tanks Dean

Are you talking .308? My build may have changed after a phone call I got tonight. It's hard to pass up an 1895 in .45-70. I may just have to own a big bore lever gun as of tomorrow morning.

[scope eye]

Yes I was referring to a 308, as far as that 45-70 goes, go for it sounds like an awesome piece of history.

Tanks Dean

[helotaxi]

Way lower than advertised by as much as 12% for some of their bullets. Issue number 81 of the varmint hunter has some very good BC comparison data by litz and the air force academy. I think I made a PDF of the article if your interested I can email it to you. Send me a pm.

Nosler is hardly the only one that has fudged the numbers a bit. Some of the Hornady and Sierra numbers were shown to be off a good bit as well.

[stomp442]

Yeah but the other manufactures were much closer to the test numbers with over estimates in the 3-4% range with some being under estimated like the Sierra Match Kings. Virtually every Nosler tested was over estimated by at least 6% with most around the 8-10% range. Nosler also lists the same B.C.s for the Ballistic tips as well as the Acubonds even though they have different dimensions. I wouldn't trust anything Nosler prints but thats just me.

Nosler has recently come out with a ALR bullet (accubond Long Range) that has listed B.C.s 80-100 points higher than Berger B.C.s depending on caliber. Dont buy that for a minute.

[keith1]

If you compare the velocities that are in Nosler load manuals to an actual chrono they are also way high at least in my experience.

Regards, Keith