THE ACCURATERELOADING.COM FORUMS


Moderators: Mark
Go
New
Find
Notify
Tools
Reply
  
what twist is my barrel
 Login/Join
 
<redheron>
posted
I have a rem 700 bdl, anyone know what the twist rate is in a factory barrel like this or can they be different. also what does the twist have to do with the grain bullet used. I have a .223 rem. What bullet weight would be good for accuracy @ 200 yards.
 
Reply With Quote
<Deafdog>
posted
Hi Redheron
Welcome to the forum.
Before I respond to your question,a suugestion if I may.
If you use the search function of this forum and type in "twist" and search "reloading"
you will get about 147 references to twist rates.Which is in effect more than you will ever want to know about "twist"

I am not a ballistician
like some of the guys on this forum and i'm sure they will explain this better than me but as I understand it..

I think your Remington would be a 1 in 12
twist.

The twist of a barrel is the distance the projectile travels to complete one revolution
ie a 1 in 10 twist is one bullet revolution in 10 inches.

The twist in the barrel gives the projectile
rotational velocity (spin) that stabilises the flight of the projectile.

The weight in grains of a projectile is relevant as the heavier a projectile, of the same calibre gets, the longer it gets.

Longer (ie heavier) projectiles need more rotational velocity (spin) to stabilise the flight of projectile.

If you shoot heavy for calibre projectiles in a slow twist barrel the bullet will tumble and you will see keyholes in the target.

The the shape of the projectile also affects things as well, as that influences the air flow over the bullet.

For example I have a BLR in .223 with a 1 in 12 twist and it won't stabilise 62 gn FMJ but will shoot 63gn semipoints fine.

The semi point stabilises where the sharper pointed FMJ develop air pressure differences between top and bottom that tumbles the bullet.(It is more complex than this but it's the best I can do.)Warren Jenson from Lostriver Ballistics is the man to talk to.He is a forum member and he explains it much better.

As far as what projectile will work in your rifle at 200yds it is really a question of "suck it and see" you will have to experiment to see what is accurate in your rifle.

Hope that helps.

Regards
Deafdog

------------------
deafdog@turboweb.net.au
http://deafdog.turboweb.net.au

 
Reply With Quote
one of us
posted Hide Post
Redheron, you can determine the twist by yourself.

Just use a cleaning rod and brush.

Mark the rod at the muzzle, pull it out until the rod has made one revolution, and measure the distance you have pulled.

Rick.

 
Posts: 1099 | Location: Apex, NC, US | Registered: 09 November 2001Reply With Quote
  Powered by Social Strata  
 


Copyright December 1997-2023 Accuratereloading.com


Visit our on-line store for AR Memorabilia