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Discussion Starter · #1 ·
Anyone know of any factory .223 target loads utilizing flat base bullets as opposed to boat tail ? Based on zeroing flat base Nosler and Hornady hunting loads, I have reason to believe that my 110 Savage may well shoot a flat base bullet better than boat tail. Thanks.
 

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In theory and all-else being equal, flat base bullets should be more accurate. Bryan Litz points out it is harder to make a perfectly symmetrical boattail in the first place. Also, the boattail dwells in the muzzle blast longer than a flat base, tending to increase initial yaw and giving more opportunity for any small asymmetry in either the bullet or the muzzle crown to apply its influence.

As to load data, though, mass is mass and density is density. If two bullets have the same construction, their density will match and if you have two with the same ogive profile (nose shape above the bullet's cylindrical bearing surface), then when you seat them with the same amount of ogive protruding from the case neck, then they will occupy the same space under the bullet, so load data should be the same.
 

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G&A showed an interesting video a few weeks ago, utilizing ultra high speed video of both flat base and boat tail bullets leaving the muzzle. The flat base bullets apparently upset into the rifling better than the boat tail thus exiting the muzzle fully ahead of the propellant blast. The boat tails were surrounded by the blast for several inches past the muzzle. The theory behind utilizing an 11 degree crown is to better match the corresponding angle of a boat tail. If your rifle has a flat crown (or round crown) that may be the reason that flat base bullets perform better in your rifle. Having a blast of propelling gases surrounding the bullet, deflecting from a less than absolutely perfect crown could certainly impact accuracy.
 

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The video, as described, sounds like it demonstrates why a boattail has to be perfect.

I don't know of anybody loading flat base match ammunition. The reason is the boattails have higher ballistic coefficients, so they buck the wind better at the longer ranges, and lots of people only want high BC's. At up to 200 yards, the flat base is easier to get shooting tight groups, and it might or might not beat the BTs at 300 and 400, depending on circumstances. You have to be a handloader, though, to have the 150-grain flat base Berger target bullets in your .308W or your 30-06 Garand loads.

The late Harold Vaughn, former head aeroballistician at Sandia National Laboratories, said the 11° crown was based on copying the 11° angle that minimizes drag on an automobile body, thinking it would carry over to supersonic bullet behavior. I don't know if he was right about that or not, but he did perform many experiments on crown angles. He concluded that as long as the crown was perfectly symmetrical around the bore axis, it would produce accuracy equal to any other crown. In his book, Rifle Accuracy Facts, Vaughn got a 270 Winchester sporter to shoot 1/4" groups at 100 yards, so he seems to have known what he was doing. My suspicion is the 11° crown works better for some simply because a slightly tilting 11° crown cutter or a lathe cutting an 11° crown on a muzzle that is slightly off the spindle centerline produces a smaller error than a steeper crown angle would do, so it's intrinsically easier to make it precise. If you make a flat, 0° crown on a lathe, you could have the barrel way off the spindle centerline and still get a perfect crown. But at any other angle, the steeper the angle, the bigger the crown unevenness.
 
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Discussion Starter · #8 ·
Just checked Powder Valley, and they have .224 flat based bullets in stock by both Berger and Hornady.
edit-
Sorry, I just noticed you were looking for "loads", not bullets.
Thanks, appreciate the effort. It appears that nobody is loading target ammunition in .223 with flat base bullets. The Nosler flat base Varmageddon hollow points in 62 grain and Hornady Varmint Express, 55 grain V-Max ( flat base ) shoot tighter than boat tail target rounds at 100 yards in my Savage 110 Storm, but they`re a bit expensive for " fun " target shooting. The PMC and Frontier boat tails are 1 MOA for groups and sub-MOA ( .6" average from POA ) for accuracy, so that`s still pretty good when one considers my less than expert marksmanship. I sure do enjoy shooting this gun and trying to improve.
 

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They proved that flat base bullets are more accurate than boattails at the Houston warehouse.......in full blown benchrest rifles but I've seen plenty of Sierra matchkings with boattails win just about every other type of rifle competition that has ever been shot. I shoot v-maxes in varmint rifles{700's and AR's} because of the terminal performance but generally speaking boattails are more accurate in my guns, my thinking is the boattail helps the bullet start straighter in conventional dies reducing run-out. Inline bullet seaters negate that issue but are a hassle in volume loading. I've owned several Ruger varmint rifles that definitely preferred flat base Hornady bullets, probably not that unusual that the way the leade angle is cut may effect accuracy with the ogive on some mfg's bullets.
Your Savage is probably the same way, you have any friends who load their own ammunition?
 

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Discussion Starter · #10 ·
They proved that flat base bullets are more accurate than boattails at the Houston warehouse.......in full blown benchrest rifles but I've seen plenty of Sierra matchkings with boattails win just about every other type of rifle competition that has ever been shot. I shoot v-maxes in varmint rifles{700's and AR's} because of the terminal performance but generally speaking boattails are more accurate in my guns, my thinking is the boattail helps the bullet start straighter in conventional dies reducing run-out. Inline bullet seaters negate that issue but are a hassle in volume loading. I've owned several Ruger varmint rifles that definitely preferred flat base Hornady bullets, probably not that unusual that the way the leade angle is cut may effect accuracy with the ogive on some mfg's bullets.
Your Savage is probably the same way, you have any friends who load their own ammunition?
Wish I did have friends that reload. I`d happily buy some flat base bullets for them to use. Considering the proven accuracy as well as precision of flat base bullets, particularly at shorter ranges ( out to about 300 yards ), I`m surprised there`s not a target offering in factory loads that uses them.
 

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Elite Competition shooters like to control their own destiny, meaning load their own ammo, not hope they third shift of a mass production plant was having a good day. 😉😉

Seriously, production ammo is about intrigue and selling the sizzle. That means sexy sounding BC's that don't matter to 99% of the population, running with utterly stupid claims like "just the tip" and selling to people who wouldn't read a white paper if their life depended upon it. Flat base bullets don't really fall into those categories.

But now that you know you need a reloading set up, think it's be writing my letter to Santa Claus. 😁

Cheers
 

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Discussion Starter · #12 ·
Elite Competition shooters like to control their own destiny, meaning load their own ammo, not hope they third shift of a mass production plant was having a good day. 😉😉

Seriously, production ammo is about intrigue and selling the sizzle. That means sexy sounding BC's that don't matter to 99% of the population, running with utterly stupid claims like "just the tip" and selling to people who wouldn't read a white paper if their life depended upon it. Flat base bullets don't really fall into those categories.

But now that you know you need a reloading set up, think it's be writing my letter to Santa Claus. 😁

Cheers
Thanks, and don`t disagree. " Elite competition shooters " in no way, shape, or fashion describes or includes yours truly!! I know that many, if not most, shooters that consider themselves " serious " load their own and can understand that. I`ve identified and zeroed two excellent predator rounds, both flat base of course, and my rifle shoots boat tails well enough at the range. I`m pretty sure though that the guy behind the gun has plenty to do with improving the precision of the shooting, so I`ll concentrate on that.
 

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So as a consideration for you, if you don't already realize this.
It's a bit difficult to make a judgement on accuracy of bullet shapes, simply by shooting factory ammo. Factory ammo is constantly swapping powders in "the same" ammo.
So if you bought some Remington Greenbox ammo today, and "the same" stuff two months later. You better not hold your breath that the ammunition is honestly and actually "The same". So was what your rifle didn't like simply the bullet? That's a leap of faith you shouldn't be making.:)

Cheers
 

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Discussion Starter · #14 ·
So as a consideration for you, if you don't already realize this.
It's a bit difficult to make a judgement on accuracy of bullet shapes, simply by shooting factory ammo. Factory ammo is constantly swapping powders in "the same" ammo.
So if you bought some Remington Greenbox ammo today, and "the same" stuff two months later. You better not hold your breath that the ammunition is honestly and actually "The same". So was what your rifle didn't like simply the bullet? That's a leap of faith you shouldn't be making.:)

Cheers
Thanks Darkker. I`ve decided that there are many, multiple factors that impact the flight of a bullet from the rifle to the target and affect where said bullet hits on said target!! It would be a daunting task to analyze and identify anything and everything that may be affecting accuracy and precision.
 

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Sorry, the video I saw was linked from FB, a place I rarely visit and it was a sponsored link. One of the concepts mentioned included the observation that due to lack of disturbance, flat based bullets "go to sleep" faster than boat tails. The natural orbital oscillations diminish quicker and provide a more accurate round. The SMLE in .303 was unremarkable @ 100-300 meters and outstanding @ 600, ie: Slow to go to sleep.

TT: From your last posting, you seem to have come to the same realization that most hand loaders acknowledge and pursue. As addictions go, it isn't as toxic as many.
 
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