# Flat Base vs Boat Tail?



## Bax* (Dec 14, 2008)

So I accidentally bought some flat based (instead of a boat tail) V-Max bullets with collet the other day to load up, and I decided to give them a try just to see how they shot out of my rifle. But it got me to thinking, what benefits and drawbacks are there to a FB bullet design as opposed to a BT design?

I did a little reading, and I am not seeing much information comparison on ballistics, but some are saying a FB design seems to kill better than a BT.

Any thoughts on ballistic differences? Can the bullet velocity change due to these designs (assuming bullet weight is the same)? Is there a difference in terminal performance as well?


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## DallanC (Jan 13, 2009)

BTs have less drag, better for longer shots.


-DallanC


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## Bax* (Dec 14, 2008)

So would they also maintain a higher velocity at longer distances due to lower drag?


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## DallanC (Jan 13, 2009)

Correct. Terminal preformance should be relatively equal for all intents and purposes.


-DallanC


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## Al Hansen (Sep 7, 2007)

What DallonC says.


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## Bax* (Dec 14, 2008)

Thanks DallanC (and Al)! I rarely find any FB bullets and the only reason I ended up with these is because I assumed they were all BTs. I think the only other FBs I have loaded were for my Hornet (they sure suck to seat).


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## Al Hansen (Sep 7, 2007)

Hornady Vmax's in .204 and .223 are FB's. I love em. Hard hitters. :O||: My Hornady Amax for the .243 is a BT.


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## longbow (Mar 31, 2009)

Generally, FB stabilize quicker. The BC isn't usually as good but who cares out to 300 yards. For longer range Boatails are a better choice. With today's bullets we're really splitting hairs.


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## BPturkeys (Sep 13, 2007)

They both will hit the ground at exactly the same time. oh,...yes they will  (another interesting but worthless fact)


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## chet (Sep 7, 2007)

> They both will hit the ground at exactly the same time. oh,...yes they will (another interesting but worthless fact)


but the boat tail will travel a few yards further before hitting the ground :mrgreen:

generally speaking, a flat-base bullet will have more bearing surface than a boat-tail of equal caliber and weight. 
more bearing surface = more pressure
more pressure = more velocity
What that really means is that you need to back down on your powder and work up a new load.

A higher ballistic coeficient not only aids in retaining velocity/energy down range, it also aids in wind resistance. We can easily predict trajectories with a few simple tools/knowledge..... but it can be really tough to predict the wind drift down range.
Like longbow said, out to 300 or so yards-we really are splitting hairs.

As fair as killing "better"...... I don't see how there could be any difference.
the internal design of the bullet (partitioned/bonded/soft/hard/ect) has the real say in which bullet kills "better". And that also is dependant on impact velocity.

On a side note, I do generally find it easier to shoot tiny groups with flat-base bullets. But I do have some boat-tail loads that perform just as good.


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## Frisco Pete (Sep 22, 2007)

I think some of the "killing better" theory floating around is due to the prevalent idea that _conventionally constructed_ simple cup-and-core boattail bullets shed their lead cores easier upon impact with flesh - rather like squeezing a banana out of its peel in concept. Whereas flat-base bullets are supposed to hold and support the core better. This idea has attained "conventional wisdom" status in many shooting circles.

I have some doubts on the veracity of this concept, even though I have seen core/jacket separation with at least one 6mm/100-gr Hornady BTSP. But a sample of one is nothing to go by - even though some hunters buy whole new guns and bigger/faster calibers based on a sample of one failure :roll:

Whether a bullet shoots accurately and how well it is constructed is more important to me for normal hunting than the shape of the base. As mentioned, there are some length differences, and some guns just prefer flat-bases, etc. At _normal hunting ranges_, drop differences are fairly insignificant.


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