Flat base VS boattail VS rebated boattail

[Grimstod]

Show what are the differences? I always thought that boattail bullets were more accurate cause they let the bass out of the barrel more gently then a flat base. So as I have been reading more about it then I start finding these rebated boattails. Now I am confused. Can you guys explain to me the prose and cons of each of the three? Thanks for your help.

 

[M14AMU]

Twenty years back I had much communication with Robert McCoy who was the Chief Ballistics Officer at Aberdeen Proving Facility in Maryland. Bob helped me design my bullet making dies and based upon what Bob had discovered was that a bullet with the appropriate angle of boat-tail and afixed with a rebated feature outperformed all other bullets and projectiles that he had tested for the military through his sparkgraph range facility by at least 5%. Now...5% doesn't sound like much but if two competitors both shoot clean targets, that 5% would mean a lot...on X count!! Bob also allowed that any bullet with a 13 degree boat-tail such as the Sierra 168 gr. HPBT has the same drag function as a flat-based bullet. You'll hear from the BR crowd that flat-based bullets are the HOLY GRAIL of accuracy but for my game I'll stick with the boat-tails!

 

[Joe R]

Generally speaking short range bench rest shooters like flat base bullets because that's what works best for them, long range shooters use boat tail bullets because that's what works best for them.

It depends on the type of shooting you're going to do. I'm reading Bryan Litz book "Accuracy and Precision for Long Range Shooting" and there is little doubt that boat tails are the only way to fly based on ballistics. There is a Flat Earth Society and they still insist that the Earth is flat, and they are absolutely sure of it.

 

[JRS]

LAPUA developed the D46 rebated rim bullet in the 1930s. I had a few boxes of 150 grain 7mm bullets that I sent to Kevin Thomas. My father used to compete with these in Europe. Kevin and his boss were greatly surprised. They had no idea that LAPUA made these in the 150 grain weight. As time moved ahead, they became more and more streamlined with the boat tail and VLD. When shooting beyond 300 or so yards, the boat tail and VLD are the only way to go. Anything inside 300 yards, the flat base bullet gives up nothing whatsoever to the others.

 

[WyleWD]

You'll hear from the BR crowd that flat-based bullets are the HOLY GRAIL of accuracy but for my game I'll stick with the boat-tails!

Agree. Will take the boat tails even for 100yd & 200yd group shooting.

But by all means let YOUR rifle tell you what it likes. WD

 

[JRS]

Grimstod:

There was an article written by Brian Litz, that goes into great detail about the different designs, and their pros and cons. I have a copy of it in my notes, but you might find it somewhere on the Berger website. Brian explains the distances needed for each design to "go to sleep" and produce their best accuracy.

 

[Joe R]

It seems to me that the Berger VLD's are not suited for short range because they need room/space/time to go to "sleep". The VLDs are intended for long range. If you're into short range the regular boat tails or flat bottoms would work just fine.

 

[CJ6]

My short range (6PPC) uses BTs (65gr Barts).

 

[CatShooter]

I remember that back in the 80's, Hornady made some beautiful rebated, VLD bullets in 7mm and 30 cal (maybe others)... but they didn't make them for long.

I don't know why they were taken off the market. Maybe lack of interest???

 

[KMart]

There was a thread on the Hornady 190 gr rebated base bullets back in Jan

http://forum.accurateshooter.com/index.php?topic=3832995.msg36333269#msg36333269

 

[JRS]

I remember that back in the 80's, Hornady made some beautiful rebated, VLD bullets in 7mm and 30 cal (maybe others)... but they didn't make them for long.

I don't know why they were taken off the market. Maybe lack of interest???

It was actually an experiment that proved to be no more accurate than was expected. We've tried many things, over many years of experimenting. It would appear, that we have come full circle.

 

[GerryM]

I asked that question a while ago.

Here's what i have for answers

Flat base bullets are good to about 300 yds then the Boat tail kicks in.

The BT shoots better past 300 yds. There is little differance in in accuracy between the standard BT and the rebated BT,

Flat base bullets shoot very well at long range but the BT shoots a bit better the flat base drift a tad more

 

[hogpatrol]

You'll hear from the BR crowd that flat-based bullets are the HOLY GRAIL of accuracy but for my game I'll stick with the boat-tails!

Agree. Will take the boat tails even for 100yd & 200yd group shooting.

But by all means let YOUR rifle tell you what it likes. WD

+1 on the latter.

 

[mshelton]

There are schools of thought out there about the flat base and how it exits the barrel. The flat base exits the muzzle clean meaning that it's an abrupt exit and the bullet escapes any influence the also escaping gasses may have on it's rear end unlike the boat tail where the bearing surface has left the barrel but the boat tail section is still in there. I talked to Bill Nemi about it and other things one day and my eyes glazed over on quite a few topics but I believe that was the jist of it from him regarding flat based bullets having the advantage in short range. That the bullet exited the barrel cleaner and did not need a lot of distance to settle down.

 

[Grimstod]

Thank you everyone for you many responses. There were some places suggested that I go read more on and I will defiantly do that.