04 April 2011, 09:47
drewhenrytntProjectile shape and construction Questions
My rifle is a 300RUM.
At what distance if any do boattail bullets become necessary?
Given the velocity of factory 200gr A-Frames Remy ammo around 3K, at what approximate distance will this flat based bullet become a hindrance?
Anyone have experience with GS Custom 160HV? Or GSC SP bullets?
04 April 2011, 10:22
GhubertPing me your email address and I'll email you a copy of a spreadsheet I put together to do ballistic comparisons with.
The short answer to your question however, in my opinion, is that for short range ie sub 300M shooting it appears that the custom flat based bullets are intrinsically more accurate as they seem easier to make more consistently but that at distance the better consistency is nullified by the better ballistic coefficients of the boat tail designs making them effectively more accurate at long range.
This is quite apart from any energy considerations that may come in to play if you're hunting.
In short if all other factors are equal the better BC of the BT is worth having past 300 yards, run the drops and windage for yourself and if you're hunting the retained energy figures.
A
04 April 2011, 18:03
Tyler KempAnything "long range" a good low-drag bullet will excel, especially in the wind.
04 April 2011, 20:43
Antelope Sniperquote:
The short answer to your question however, in my opinion, is that for short range ie sub 300M shooting it appears that the custom flat based bullets are intrinsically more accurate as they seem easier to make more consistently but that at distance the better consistency is nullified by the better ballistic coefficients of the boat tail designs making them effectively more accurate at long range.
I'd say that's dead on, and charts do a good job of confirming it.
One of my personal philosophy's is to keep bullet construction as simple as possible for the tast at hand. The simpler the bullet design, the easier it is to make a consistant bullet. In general a flat base bullet is more accurate out to about 300 yards, with 300 being the cross over point where a BT may perform better. IMO about 600 yards is the cross over point for switching from a standard BT to a VLD design. Others may have different opinions, and it would be great to hear them.
Since we are talking bullet construction I'd like to mention two other aspects. Bonding and partitions. Contrary to what the bullet salesmen may tell you, when you bond a bullet, you are essentially soldering the lead core to the copper jacket. As the jackets are welded to the core this is bound to introduce some eccentricities in the jacket. Since a consistant jacket wall thickness is the single most important element in constructing an accurate bullet, this could only have a negative effect on accuracy. So if you are shooting long range, and don't need a bonded bullet, I would recommend again it.
The same can be said for America's favorite hunting bullet, the Nosler Partition, and other similar designs. A partition takes almost exactly twice as many steps to make as a traditional cup and core bullet. The Jacket must be extruded in two directions, two cores must be made and seated, point formed, and the rear core crimped in place. Twice as many operations means twice as many places for eccentricity to be introduced into the bullet. This design is great for crushing bone, but not the best for LRH.