Gun Number for Wind Calls! Detailed Video! 

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Gun number is the first number of your bullet’s G1 BC. This .308 is a 5mph gun, which means he’ll add 0.1 to his wind hold per 100 yards at a 5mph wind. For the first shot at 660 yards (rounded to 700), that’s a 0.7 mil hold per 5mph.

@@BlueDevilBrew Epic, thanks Blue!!!

Thanks 👍

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Glad it was helpful!

Yes, and they are almost as good as in person. You might wear out the replay button. This is a golden ticket.

Come over to the Modern Day Rifleman network and you'll learn.

Make this plan ahead of go-time. Write the wind holds down so you can remember them. Eventually you'll be able to do this on the fly.

@@MODERNDAYSNIPER yeah I really need to get the timer out more when I shoot. Thankfully my new scope should be here today so I can actually hit the range again

You need to do your homework

Frank Galli explains it well in his book. They also did a video on it recently.

Follow the link in the description and do some “fucking” homework. ✌️ Great having you as a follower.

Do you have a ballistic calculator app on your phone? Using his 308 as an example, assume he's shooting a 176gr A-tip at 2650fps at 4000' elevation. A 5mph wind gives a wind correction of ~0.1mil at 100yds, ~0.2 at 200yds .... ~0.7 at 700yds. That means it's a 5mph gun. If you used a 6.5CM rifle instead you'd have to use maybe 7mph to get the 0.1mil, 0.2, etc corrections at the same yardages which means it's a 7mph gun. Gun number will mainly be based on bullet, muzzle velocity, and altitude.

@@tylermertz7095 so it's which ever mph in wind speed correlates to a 0.1 mil adjustment per 100yds? Maybe I'm just that clueless about it but it feels like a solution looking for a problem and someone wanting to sound Gucci. A term used for a singular point of reference like this...just seems useless

KRG W3

@@williamsweet7511 RRS has the best reputation. The ball head is important Anvil30 is very stable and easy to manipulate. I own a couple of them and it’s worth it for sure no regrets now after initial purchase.

Or, you could apply the systems in the video and stop hoping.

The Hodnett way? Never heard of her...

@@MODERNDAYSNIPER hahahaha!!!Well as the "modern day" sniper you are,and seeing how you did a DVD set back in the day with him with magpul,ide say it's strange you'de say something like that.But either way,pretty plain to tell what method you're using,even if it's using it in tard yards to make it work for the competition circuit crowds.Just saying it's toooootally obvious for anyone that's been taught the method where and who conceived it and figured it out to help evolve the community.Which is what you're doing,so keep it up man.Sniper Jesus would be proud in way I think.Imitation is the highest form of flattery..😎👍

Sure thing man, you do you!

⁠@@MODERNDAYSNIPERWhat, you think you invented this stuff? The MOA wind constant formula has been taught since the 2nd World War. Faster than what your doing and more accurate. I used it to earn American High Power Rifleman Award in Long-Range. What have you won lately?

Got you in the network! 🤘

Not a dumb question at all, and the answer to your question is YES! It's a simple modification to the formula and MOA shooters have one small addition. Take your range to the target in hundreds and divide it in half. That number is now the MOA hold. IE: 200 yards becomes 1 MOA, 300 yards becomes 1.5 MOA, 400 yds becomes 2 MOA, etc. Look at 600 yards (3 MOA) and adjust your wind speed until you have 3 MOA of drift at 600 yards. This should fill things in nicely, but a word of caution that MOA numbers won't be exact like Mils.

It's a Thunderbeast CB7

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Good to hear! Be advised: no one that I know dials for spin drift, unless you're shooting a fast-twist 308 that requires it.

@@MODERNDAYSNIPER good to know, no I have a slow twist 1:12 on an AI barrel. I’d like to eventually get into a pre fit 6.5CM and ditch the 308. I also joined MDR and I’m loving it. You guys are awesome. One day I’ll come up with the cash to go to a course of yours!

Just work it out in MOA.

Your MOA hold should be half of the yardage in hundreds. IE: 400 yds your wind should be 2 MOA, 500 yds it should be 2.5 MOA, 600 yds it should be 3 MOA.

Always

Follow the link in the description and cruise over to the network. Tons of info on this subject there.

Do you have a ballistic calculator app on your phone? Using his 308 as an example, assume he's shooting a 176gr A-tip at 2650fps at 4000' elevation. A 5mph wind gives a wind correction of ~0.1mil at 100yds, ~0.2 at 200yds .... ~0.7 at 700yds. That means it's a 5mph gun. If you used a 6.5CM rifle instead you'd have to use maybe 7mph to get the 0.1mil, 0.2, etc corrections at the same yardages which means it's a 7mph gun. Gun number will mainly be based on bullet, muzzle velocity, and altitude.

@@tylermertz7095 that makes no sense whatsoever. It sounds like you're just using a random wind speed which is giving random wind holds for the caliber. You're saying that a 5mph wind on a 308 gives a 0.1 correction. But you would need a 7mph wind to get the same correction from a 65c. That's a caliber specific number. Not gun specific. This gun number thing is all Greek to me but, it sounds like Open up one box of ammo Put one cartridge into identical guns. Down to having sequential serial numbers made on the same day You're going to get 2 different gun numbers because they're 2 different guns. I've been looking everywhere I can think of to try and understand it, and it makes zero sense to me

Gun number = full value wind speed required to shift 1 mil point of impact at 100yards So, if 5mph (full value) moves your point of impact .1 mil @100y, then you have a 5mph gun. If 5mph wind moves point of impact .2mil @ 200yds, you still have a 5mph gun (because it’d still be .1 mil at 100y, .2@200, .3@300). Examples: A) 12mph full value wind where poi shift is .1mil @ 100y = 12mph gun B) 12mph shift .2mil @200 = 12mph gun C) 10mph shift .1@100 = 10mph gun D) 10mph shift .3@300 = 10mph gun E) 7mph shift .1@100 = 7mph gun So, at 500y, with a full value wind of 5mph on a 5mph gun = .5mil poi shift. (.1@100, .2@200, .3@300, …) Then, if winds increase to 10mph on the same 500yd target with the same 5mph gun, then you’d need 1.0mil shift. (.2@100, .4@200, .6@300, .8@400, 1.0@500) Effectively, the better your gun is at cutting through the wind (higher BC & higher velocity), the higher the number. AKA, a 10mph gun will need half of the wind correction of a 5mph gun.