UPDATE PRECISION RIFLE CLASS March 12/13

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Originally Posted by Gatorvet

Great class. Great instruction. Learned a lot of great new information and reinforced some old skills.
I will be back for more! Thanks!

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I have to say this past PR class was eye-opening for me concerning some of the disparity between the Remington 700's DOPE for the 500 yard shots vs. my Savage's DOPE at 500 yards... I have seen numbers vary here and there but 10.5 MOA vs. some of the higher numbers shooting the same ammo, such as 12.5 to 14, surprised me. Usually at 500 I can give a ballpark MOA call and guys get on the steel quickly... Even the 10.5 (my Savage) vs. the Rem 700's 12.5 (which one was still low IIRC) is 10+ full inches of difference (2 MOA @ 500 = 10"). I'm still getting great stuff from EVERY class... I'm sure my Savage was 2" shorter than the 2 700's the other Snipers were using.

Another great plus was the conditions that made spotting bullet trace child's play... the bullet trace all the way to the target was so distinct Ray Charles could have seen it... another great plus was the opportunity to get better at spotting... the unsung hero of LR shooting.

2" shorter barrel and it was still getting hits 10" higher? What are you thinking is the disparity there?

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Originally Posted by Evil_McNasty

2" shorter barrel and it was still getting hits 10" higher? What are you thinking is the disparity there?

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2" is only equivalent to appx 50 fps, so I would stretch to say it might have been twist rate. If the twist rate is the same on all tubes, someone is losing gas somewhere.

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Originally Posted by Jafar

2" is only equivalent to appx 50 fps, so I would stretch to say it might have been twist rate. If the twist rate is the same on all tubes, someone is losing gas somewhere.

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I used to subscribe to that general basic formula until I started seeing great variations that went both ways. YF brought his 16" Rem 700 out and it was FASTER than another .308 we shot... the two Rem 700's with longer barrels were SLOWER than my shorter barreled Savage.

In short, the more odd things I see the less "sure" certain things are... twist rates, type of rifling, number of lands/grooves, bore wear, etc., lots of factors that could add up for sure.

One thing was clear... ballistic charts and math is good, but as we all know, field testing is where it's at... another great benefit to training... seeing things that depart from the norm.

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Originally Posted by Airgator0470

I used to subscribe to that general basic formula until I started seeing great variations that went both ways. YF brought his 16" Rem 700 out and it was FASTER than another .308 we shot... the two Rem 700's with longer barrels were SLOWER than my shorter barreled Savage.

In short, the more odd things I see the less "sure" certain things are... twist rates, type of rifling, number of lands/grooves, bore wear, etc., lots of factors that could add up for sure.

One thing was clear... ballistic charts and math is good, but as we all know, field testing is where it's at... another great benefit to training... seeing things that depart from the norm.

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Have you seen Todd Hodnett running 18" .338LM's? He says he's getting better results with shorter barrels and will possibly never build other rifles with anything longer than 20" tubes.

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Originally Posted by Airgator0470

I used to subscribe to that general basic formula until I started seeing great variations that went both ways. YF brought his 16" Rem 700 out and it was FASTER than another .308 we shot... the two Rem 700's with longer barrels were SLOWER than my shorter barreled Savage.

In short, the more odd things I see the less "sure" certain things are... twist rates, type of rifling, number of lands/grooves, bore wear, etc., lots of factors that could add up for sure.

One thing was clear... ballistic charts and math is good, but as we all know, field testing is where it's at... another great benefit to training... seeing things that depart from the norm.

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Maybe the faster rifles have more wear on the rifling? Less friction

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no one asked, but I was curious so I looked it up.

Twist rate vs velocity

http://bulletin.accurateshooter.com/...ity-litz-test/

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I did not think 1:10 vs. 1:11, which perhaps is the most common twist in .308 Winchester, would had made the difference, both rifles have conventional Enfield rifling so that's out... I read a lot where the TYPE of rifling, such as polygonal, results in less pressure allowing for hotter loads and more velocity... common in the 6.5G vs. 6.5SPC battle.

The only thing I can think of is my Savage barrel must be well honed and seasoned... for a sub $400 rifle, I wish I had bought 5 of them.

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Originally Posted by Evil_McNasty

Maybe the faster rifles have more wear on the rifling? Less friction

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Was my post in the works...