spitzer/boatail accuracy?

[steviebee]

HI,

Whats the main accuracy diffrences between spitzer (flat bottom) heads and boatails if any, over normal hunting ranges?

cheers

[Sikaslayer]

Flat bases can be better over the normal hunting ranges.

[Night Stalker]

Had a good search and this seems to be a consensus,

Flat-base bullets are inherently more accurate than boat tail bullets because it is almost impossible to form boat tails perfectly. Even so, over long range, a boat tail’s ballistic benefits out weigh any manufacturing flaws.

There are a couple of drawback to flat-based bullets ballistic efficiency the first is that their center of gravity is more toward their rear, which doesn’t help stability the second is that as flat-based bullets pass through the air, the air flowing over the bullet’s surface wants to slam back together at the base which creates quite a bit of turbulence resulting in increased drag, both the problems are reported to be worse after about 350 yds as the bullet slows.

Boat tails increase the ballistic coefficient of bullets, which helps them overcome air resistance, turbulence and wind deflection. The shape also helps the air flow transition over the heel of the bullet and reduces the base diameter resulting in less base drag which helps over longer distances.

I have always used Nosler ballistic tips with boat tails for stalking with my 25-05 as I may need to take shots over normal shooting ranges due to the land I shoot over. If I know I'm sitting in a box I use a 303 with flat based sierra pro hunters, I recently found some of these for £11.40 a box of 100 in 25 cal so picked up 300 to try in the 25-06

Rick

[kemen4]

Coincidentally, on 6mmbr. there is a review of Bergers new Column bullet. Seems it has been developed for greater precision in bench rest at 100 to 300: and its a flat base.
But for long range there are other factors to consider.
I was told by a maker of bullets that at practical hunting distances a BT is another machine operation and potential source of error.

[Lightyear]

I might be mistaken but believe "spitzer" means pointed and is not a reference to the design of the base of the bullet, be it a boat-tail or flat base.

I do not believe that one or the other over "normal hunting ranges" will be inherently better than the other with regard to accuracy, but that one or the other might well suit your particular rifle better than the other.

One consideration might be that boat-tail bullets tend to have an OAL greater than the equivalent weighted flat based bullet.

For longer ranges over 300 or so yards the higher BC of VLD or boat-tail pointed (and hollow pointed) bullets with secant ogive does then start to manefest itself.


Cheers + ATVB

Philip