Shattering the Preconceptions of Barrel Length

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Shattering the Preconceptions of Barrel Length

Postby Texas Sheepdawg » Mon Jun 02, 2014 11:58 pm

Well. I definitely learned something today. And you guys with 16" Thumpers, you're gonna like this article.
http://www.thetruthaboutguns.com/2013/1 ... -accuracy/
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Re: Shattering the Preconceptions of Barrel Length

Postby LegendInMyOwnMind » Tue Jun 03, 2014 9:21 am

Thanks Dawg! Nice article. That test was done about 40 mi. from me....
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Re: Shattering the Preconceptions of Barrel Length

Postby PRKL8R » Tue Jun 03, 2014 1:42 pm

It is an eye opening article. While the short has an edge in some guns how accurate is accurate enough for the job? The 16'' or 20'' Thumper is fine for me. I prefer the shorty for portability. I have a Savage Striker in 308 that with my handloads is as accurate as any of the .308 rifles I have owned and it only has 9'' of rifeling after you subtract the chamber and muzzlebrake.
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Re: Shattering the Preconceptions of Barrel Length

Postby MarkCO » Tue Jun 03, 2014 8:08 pm

I am not sure that is all that "shattetering" unless you listen to gunrag writers.

Most of my precision long guns have 18 to 21 inch tubes, typically 4" to 8" shorter than the average weekend warrior prefers. At least in the circles I run in, 16" to 20" won't get you any sneers when the targets are getting hit repeatedly. The only reason I have 18" ARs over 16" is because the longer gas systems are smoother and longer lasting than the short systems.
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Re: Shattering the Preconceptions of Barrel Length

Postby Texas Sheepdawg » Tue Jun 03, 2014 10:20 pm

I've just always assumed the longer barrels provided better accuracy. In this article, it did note that the FPS did improve, but only by around 300FPS. If I remember the conversation correctly, In the Thumper, that figure was approx 126-129 FPS faster out of the 20" from what Tim told me. I'm sure he will correct me if I'm wrong. Running that through a ballistic calculator for the 230 Gr FMJ......
Zero @100Yds
Sight height 2"
2500 FPS @ muzzle (TKO 37)
1563 FPS @ 200 Yds (TKO 23)
-6.9" drop

129fps drop in speed provides

2371 FPS @ muzzle (TKO 35)
1470 FPS @ 200 Yds (TKO 22)
-8.0" drop.

That's only a 1.1" drop at 200 Yds.
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Re: Shattering the Preconceptions of Barrel Length

Postby Hoot » Wed Jun 04, 2014 4:14 am

And yet some reloaders will spend countless hours and reloading supplies trying to get 130 more fps out of their loads, some times risking damaging their rifles and themselves. Think about it. Someone comes around and says you know that 2500 fps you're driving those 230gr FMJs at? I have a process that can reliably yield 2630fps and people would throw palm branches at his feet. If that person then revealed that he just got a 4 inch longer barrel, folks would suddenly dismiss him for adding such an undue burden to his enjoyment. We are a strange lot... :lol:

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Re: Shattering the Preconceptions of Barrel Length

Postby Texas Sheepdawg » Wed Jun 04, 2014 4:45 am

That's so true. And I want everyone to remember that my 2500FPS was achieved through months of cautious testing and using a Crimp method that is not commercially available. I was using the basic results info as an example because I have the data readily available. I did not post any powder charges so before you guys run to the bench and try to duplicate my data, you definitely need to remember that a 230 FMJ .451 bullet flying at 2500 FPS out of thumper is definitely way above SAAMI pressure Specs for the cartridge. What works in my rifle may destroy yours and take you out of the game as well. I'm warning you all, don't try this at home.
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Re: Shattering the Preconceptions of Barrel Length

Postby MarkCO » Wed Jun 04, 2014 7:48 am

Americans suffer from "magnumitis" and lack of practice. That ends up being a quest for 3500 fps so that if you clip a deer in the hoof, it will flop over dead. Europeans shoot moose and stags with 6 to 7mm slugs at 2500 to 2800 more often than anything else.

I no longer even own a Magnum rifle caliber, just don't see the need. Knowing your DOPE means you actually have to shoot the guns and keep track of things. I have shot game at distances some would never consider and some even call "unethical". The horsepower of the 450 is impressive, and there are certainly benefits to the caliber over "faster" rounds. But, for me, velocity is secondary to energy. I can make adjustments for drop, but I can never get more energy on target by shooting skill. When I look at loads, I want to deliver the most energy, at range to do the job on target.
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Re: Shattering the Preconceptions of Barrel Length

Postby Texas Sheepdawg » Wed Jun 04, 2014 11:44 pm

And the Taylor Knock Out value of a round is where the energy tells the story.
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