Boat Tail -vs- Flat base Bullets

[Heavy C]

I'm wondering if there's any real advantage to a boat tail versus flat base bullet in rifles for hunting applications.  Mainly deer at this point.  I'm trying to develop a load for my 6mm utilizing 100 grain bullets. 

From what I've read boat tail design bullets have higher ballistic coefficients, but aside from that would it have any impact on take-down ability either way?  I already know about shot placement too.

Any insights would be greatly appreciated.

Thanks in advance for your help.

[Wyo. Coyote Hunter]

  H C. I load lots of boat tails, they are easier to get started in the case when seating the bullet, but their chief advantage is at long range... I would say in excess of 300 yards... I ask a question similar to this, and for most deer hunting unless one is into long range shooting, flat base are fine. My pal's rifle shoots best with flat base, and when I loaded my first rounds for my .300 H & H they were flat base and shot just fine.....

[Heavy C]

Thanks.  So far all I've shot out of this little rifle is factory stuff...Federal Power-Shok, but I don't know if the bullets are BT or not.  It likes that ammo and would very much like to duplicate that load.  Well as close as you can get to duplicating factory loads.

[securitysix]

Wyo has it down.  Flat base is fine.  Boat tails gain an advantage on retained velocity and thus energy downrange, but this doesn't really come into play until you get out past 300 yards.

From what I've read, the flat based bullets will actually give better penetration inside 300 yards anyway, just due to the distribution of their mass.  

That said, I'd pick a bullet that will both shoot accurately out to the ranges you expect to be shooting and still perform adequately at the velocity you should still have at those ranges regardless of whether it's flat based or boat tailed.

[billy_56081]

From what I understand from benchrest shooters is that a poor crown effects boat tail bullets more than flat base. The idea ia that the gas escaping on a slightly bad crown pushes on the boat tail causing slight instability. If you have a rifle that won't shoot boat tails worth a darn, have your barrel crown touched up.

I have also heard that flat base bullets hold together and don't lose there core as easily.

[1sourdough]

 I have loaded some BT bullets just because they go into the case easier. In most cases a little chamfer will guide the fb bullet in just fine. With two bullets of the same weight & make, BT & non BT, the BT will be longer. This can take take up more space in the case when seated to a proper COL for the chamber. In some cartridges I see comments about this being an issue, as in the 284 win. I usually hunt where the shots are relatively short range. More often than not I now buy the FB bullets, or at least ones with a short taper.

[Tom W.]

I'll buy the BT, because as stated before, they load easier, and my rifles really do like them. I shoot Single Shot rifles, so my COL ain't "by the book."

[Heavy C]

Wow, thanks for all the replies guys.  I'm shooting and Encore rifle with a good crown.  As stated before it is very accurate with that Federal ammo.  Since I now have a decent amount of brass I want to reload for this rifle.  I guess I'll just buy some of both and see how it likes each.  Thanks again for your help.

[Wyo. Coyote Hunter]

  H C, if I were starting out to load 100 grain for a 6mm, I would get IMR 4350 powder, cci 200 and 250 primers, and 100 Serria Flat Base, and 100 Nosler BTBT. That is a good powder, easy to find. Some times a hotter primer helps. Those two bullets have always been very accurate for me....

[Heavy C]

Thanks for sharing those loads.  I do prefer the 100 grain bullets over anything else.  My Dad used to load 110 grain bullets back in the 80's.  He has passed away and I've been unable to find that load in his notes.

Has anyone had any experience with Barnes bullets; specifically the 115 grainer?

[Dave in WV]

Boat tails have an advantage.... they're easier to load. Use a "VLD" chamfer tool and the flat based bullets load easier. As posted already, with ranges under 300 yards the boat tails have no real advantage ballistically.

[calvon]

Boat tail bullets are slicker and go through the air better but only at subsonic velocities, i.e. under about 1100 feet per second.

Definitely an advantage at ranges around a thousand yards, but that's all.

[billy_56081]

Boat tail bullets are slicker and go through the air better but only at subsonic velocities, i.e. under about 1100 feet per second.

Definitely an advantage at ranges around a thousand yards, but that's all.
[/quote



HUH?? I think you better do a little more reasearch.

[gary0529]

Billy,
His data is probably closer to the truth than what you think- go to "Advanced Ballistics and Long Range Shooting" by Brian Litz.
He gives the answer as to when and why BT designs work-there is actually a trade off in accuracy -flat based bullets are generally more accurate in closer in ranges-that is under 600 or so yards at normal velocities.

The slight-and I mean very slight- advantages with the BT don't show until speeds drop and distances increase.

Read the text-not too technical and explains just about everything you thought you knew.
Nope- not related to Litz or have any dog in the fight.


Gary

[billy_56081]

180 grain Hornady .308 BT

Range Velocity Impact Drop ToF Energy Drift
0 3000 -1.5 0 0 3597 0
100 2784 0 2.24 0.11 3098 1.09
200 2583 -3.01 9 0.22 2667 3.12
300 2391 -11.27 21 0.34 2285 6.64
400 2210 -25.62 39.1 0.47 1952 11.83
500 2035 -47.15 64.37 0.61 1655 18.89
600 1869 -77.1 98.06 0.76 1396 28.05
700 1713 -117.03 141.74 0.93 1173 39.56
800 1568 -168.83 197.28 1.12 983 53.7
900 1435 -234.78 266.97 1.32 823 70.73
1000 1317 -317.56 353.5 1.53 693 90.88



180 grain Hornady .308 FB

Range Velocity Impact Drop ToF Energy Drift
0 3000 -1.5 0 0 3597 0
100 2770 0 2.25 0.11 3067 1.14
200 2557 -3.06 9.06 0.22 2613 3.3
300 2355 -11.46 21.21 0.34 2217 7.08
400 2164 -26.17 39.67 0.47 1872 12.68
500 1980 -48.34 65.59 0.62 1567 20.32
600 1807 -79.41 100.41 0.78 1305 30.29
700 1646 -121.17 145.92 0.95 1083 42.87
800 1497 -175.76 204.27 1.14 896 58.38
900 1364 -245.86 278.12 1.35 744 77.11
1000 1249 -334.59 370.6 1.58 624 99.23



Neither bullet has reached subsonic yet and the flat based bullet has more drop and wind drift.

[huntswithdogs]

Heavy,

While I shoot mainly flatbased, boattails shoot about the same outa my 243. In a hunting situation, unless you're shooting really long distances, I'd shoot whatever. My 243 load shoots Hornadys, Sierras and Rem Corelokts close enough to the same POI that I can and do use which ever I can get at the time. If you're needing a good powder choice, don't rule out H4831 or H414. 243s seem to work better when loading the cases with a powder that fills the case the most. If your hunting will stay inside of 250yds, ya might also give the Hornady 100gr round nose a look. These things will flat put the meat on the table for ya.


HWD

[billy_56081]

Billy,
His data is probably closer to the truth than what you think- go to "Advanced Ballistics and Long Range Shooting" by Brian Litz.
He gives the answer as to when and why BT designs work-there is actually a trade off in accuracy -flat based bullets are generally more accurate in closer in ranges-that is under 600 or so yards at normal velocities.

The slight-and I mean very slight- advantages with the BT don't show until speeds drop and distances increase.

Read the text-not too technical and explains just about everything you thought you knew.
Nope- not related to Litz or have any dog in the fight.


Gary

I am not disputing that flat based bullets are probably more inherintly accurate. What I am disputing is the statement "Boat tail bullets are slicker and go through the air better but only at subsonic velocities, i.e. under about 1100 feet per second."  .

[Heavy C]

Thanks HWD.  I appreciate that insight.  With my 6mm all of my shots are definitely under 250 yards.

Billy, I see your point.  When I read the statement it struck me as odd too.