THE ACCURATERELOADING.COM BIG BORE FORUMS


Moderators: jeffeosso
Go
New
Find
Notify
Tools
Reply
  
What twist for... Login/Join
 
fritz454
one of us
posted
I'm getting started on another bunch of rifles here shortly but I think I've been using twist rates that are on the slow side after reading some of the recent post here about that subject.

What would you suggest for a 475 M'bogo I use a 14 last time but am thinking to go to a 10?

Also a 500 A2. I again used a 14" but think a (" bight be a better option.

Lastly for a 550 mag. My first one had a twist of 16" but I think I may need to get that to 12" or so.

No real reasons to change, all my other projects have shot just fine but I want to use these specifically for heavier bullets than normal for caliber. Also the bullets will be mono metal and so long for weight.

All thought are appreciated.

John
 
Posts: 855 | Location: Belgrade, Montana | Registered: 06 October 2000Reply With Quote
500grains
One of Us
posted Hide Post
470 mbogo - 1:10
500 A2 - 1:10
550 mag - 1:12

My purpose: Keep long bullets, such as brass solids, stable in flesh, especially when hitting bone. Side benefit: decreased bullet yaw in the event that you use very high velocity loads. Downside: slightly higher pressure, but not an issue unless your loads are right at the very edge of the safety limit.
 
Posts: 18352 | Location: Salt Lake City, Utah USA | Registered: 20 April 2002Reply With Quote
woodsracer
One of Us
Picture of woodsracer
posted Hide Post
I was discussing this same topic with Mr. Mbogo himself about the .470 Mbogo and he noted this in a PM:

quote:
HI Jeff,
I don't think the 1 in 10 is too much. With all the modern bullets and the low pressures the Mbogo works with a 1 in 10 would be a good choice. the bullets will stand up and the pressures will still be moderate. I would consider it for sure.


He also noted that a #6 contour should be about right for the barrel. You want a diameter of at least .750 at 24 inches. thumb


"They who would give up an essential Liberty for Temporary Security, deserves neither Liberty or Security." ---Benjamin Franklin


"SIC SEMPER TYRANNUS"
 
Posts: 693 | Location: Middle Tennessee | Registered: 16 October 2005Reply With Quote
fritz454
one of us
posted Hide Post
Thanks guys,

I haven't had any noticable problem with the slower twists but since I want to run heave for caliber bullets anyway I figure a faster spin will help.

I'm going with 475-10" / 510 -10" / 550 - 12"

Thanks
 
Posts: 855 | Location: Belgrade, Montana | Registered: 06 October 2000Reply With Quote
woodsracer
One of Us
Picture of woodsracer
posted Hide Post
quote:
Originally posted by fritz454:

I haven't had any noticable problem with the slower twists but since I want to run heave for caliber bullets anyway I figure a faster spin will help.

I'm going with 475-10" / 510 -10" / 550 - 12"


Sounds good to me! thumb


"They who would give up an essential Liberty for Temporary Security, deserves neither Liberty or Security." ---Benjamin Franklin


"SIC SEMPER TYRANNUS"
 
Posts: 693 | Location: Middle Tennessee | Registered: 16 October 2005Reply With Quote
.366torque
One of Us
posted Hide Post
quote:
Originally posted by fritz454:
I'm getting started on another bunch of rifles here shortly but I think I've been using twist rates that are on the slow side after reading some of the recent post here about that subject.

What would you suggest for a 475 M'bogo I use a 14 last time but am thinking to go to a 10?

Also a 500 A2. I again used a 14" but think a (" bight be a better option.

Lastly for a 550 mag. My first one had a twist of 16" but I think I may need to get that to 12" or so.

No real reasons to change, all my other projects have shot just fine but I want to use these specifically for heavier bullets than normal for caliber. Also the bullets will be mono metal and so long for weight.

All thought are appreciated.

John

Holy S**T!!! A 338 Win must feel like a 243 for you! Big Grin
 
Posts: 3785 | Location: B.C. Canada | Registered: 08 November 2005Reply With Quote
  Powered by Social Strata  
 


Copyright December 1997-2023 Accuratereloading.com


Visit our on-line store for AR Memorabilia