What is leade

[Iron Sight]

The term "Leade" is used sometimes on this forum.

What is Leade?

Thank You

 

[454PB]

Leade is an area of minor taper just ahead of the rifling origin. Think of it as a funneled area just ahead of the chamber throat.

 

[buttrap]

Pretty much the distance the bullet has to travel before it hits the rifling. It will vary with differant style bullets and how they are loaded.

 

[Walkalong]

The part of the bore just past the neck portion of the chamber before the rifling starts is generally called freebore. Then there's the leade where the rifling has been partly cut away. This short section from where the rifling starts to where it is full rifling is the leade. It is tapered. IIRC

Here is an article I just found that touches on it, although it is primarily talking about revolvers.

 

[ranger335v]

It's sorta like "headspace" for the bullet!

 

[Mal H]

It is similar to the "forcing cone" found in revolvers, but it's a lot harder to see so you usually don't know it's there.

 

[Walkalong]

Hard to explain too.

 

[rcmodel]

Chamber reamer drawing.
"F" is case mouth.
"G" is free-bore dia. between the case and Leade.
"N" is the free-bore length between the case and the Leade.
"R" is the throat or Leade.
"H" is reamer pilot, or rifling land dia.



rcmodel

 

[Walkalong]

Yea, that is what I was trying to say.

Nice drawing. Thanks rcmodel.

 

[Bullet]

From SAAMI’s Glossary -

LEADE (LEAD)
That section of the bore of a rifled gun barrel located immediately ahead of the chamber in which the rifling is conically removed to provide clearance for the seated bullet. Also called Throat or Ball Seat.

http://www.saami.org/Glossary/display.cfm?letter=L

 

[Shoney]

It is interesting how all the definitions say similar "stuff" in different ways.

Sniper Country’s compendium does not list leade??????????, but does have:
Freebore - (aka ‘barrel throat’) The distance a bullet must travel between chamber and bore before its bearing surfaces contact the lands of the rifling, the purpose being to delay resistance, hence prolong pressure built-up. It cannot be too much, however, as that can cause instability in the bullet. This distance will vary from rifle to rifle, as well as according to the preference of the handloader, as some prefer the bullet to touch the lands, while others prefer it to be further away. Care must be taken not to make this distance too great, as this will adversely affect accuracy. It is not advisable to have the bullet touch the lands, either, as that can increase pressure levels significantly.

And SAAMI’s compendium says
FREE BORE
A cylindrical length of bore in a firearm just forward of the chamber in which rifling is not present. Associated with bullet jump.
LEADE (LEAD)
That section of the bore of a rifled gun barrel located immediately ahead of the chamber in which the rifling is conically removed to provide clearance for the seated bullet. Also called Throat or Ball Seat.

The lead is a fixed distance, while the freebore varies with the seating depth of the bullet.

 

[Shoney]

Please Omit!

 

[Shoney]

Please Omit!

 

[rcmodel]

That section of the bore of a rifled gun barrel located immediately ahead of the chamber in which the rifling is conically removed to provide clearance for the seated bullet.

I think it has morphed into much more then just bullet clearance over the years!

Roy Weatherby started the excess free-bore ball rolling many years ago to hold down pressure on his hot loaded Magnums.

Now, a lot of rifle manufactures are doing the same thing with excess free-bore for liability reasons.

Bullet clearance can't be all that goes into it anymore, when you can't hardly reach the rifling with a cleaning rod on some new rifle brands!

rcmodel

 

[USSR]

Bullet clearance can't be all that goes into it anymore, when you can't hardly reach the rifling with a cleaning rod on some new rifle brands!

That's spelled R-E-M-I-N-G-T-O-N.

Don