Should I lengthen the throat

I

Ironworker

New member
Just bought a Hornady "Lock-N-Load" Straight O.A.L. guage . This rifle will be dedicated to shooting 65gr-80gr bullets, with an occasional 60gr V-max. So starting with 69gr Sierra TMK bullets . Following the directions C.O.A.L. is 2.453 ,then using a 1" Sinclair Bullet comparator at the OGIVE it measured 1.979. I've been advised to seat bullets .015 away from lands and move.005 into lands until touching . Gunsmith that chambered this rifle said He could lengthen the throat if needed . So my question is, is lengthening the throat needed ? Why would I want to do this ? 22-250
 
Oal

When the full diameter of a bullets bearing surface goes below the case mouth, deeper into the case, neck tension is less. The powder charge may become compressed, stopping deep seating of the bullet. The bullet may fall into the case, if the powder doesn't stop it. The bullet ogive should not go below the case mouth .
 
then using a 1" Sinclair Bullet comparator at the OGIVE it measured 1.979. I've been advised to seat bullets .015 away from lands and move.005 into lands until touching . Gunsmith that chambered this rifle said He could lengthen the throat if needed.

The first thing I would do is determine the distance from the lands to the bolt face. Because I am the only reloader that insist on the running start; also known as bullet jump; I do not have the same problems other reloaders have when trying to determine maximum overall length.

I do not like the ideal my bullet is setting against the lands when the trigger is pulled, I want my bullets to build up speed before they hit the lands.

Back in the old days some reoladers gained a small advantage when ‘throating’ their chambers. A few throated their 300 Win Mag chamber and increased the length of the chamber by increasing the length of the neck. By throating they were able to move the bullet out, this allowed for ‘more powder’.

F. Guffey
 
If you do much shooting with a .22-250 you can find yourself "chasing the lands" as the throat erodes.
As long as you don't get into the oddity that 243winxb warns against, I wouldn't fool with it.
 
I'm really confused by your post. Perhaps, need another cup of coffee.
SAAMI shows 2.350 as "max" (whatever that means) oal for the 22-250.

So, you're over 100 thou longer- until you hit the lands. Which, as others posted, may pose an issue depending on the bullet you're seating.

Gunsmith that chambered this rifle said He could lengthen the throat if needed . So my question is, is lengthening the throat needed ? Why would I want to do this ? 22-250
Click to expand...

Beats me. Perhaps I've missed something.

I wouldn't even be thinking about messing with the leade until you see how it shoots.

Since you're able to jam the bullet into the rifling (again, without it being seated out too far in the case), I don't see what the issue is... you are already longer than spec.

The only reason to lengthen the leade is to gain more space to seat-out VLDS.

The barrel on my .260 is chambered in .260 "Match"- it has .07 more freebore than SAAMI spec .260 to be able to seat the 140 Amax VLD's I use in it.

Why do you feel you need to seat these out longer? Too much bullet in the case?

This is a good read from Berger on VLD's:

http://www.bergerbullets.com/vld-making-shoot/
 
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Yep, measure the distance from the lands to the bolt face. That's info you need. Then seat your bullets off the lands, and not jammed into the lands. I am most definitely in Mr Guffey's camp on wanting a running start for the bullet.

And, as suggested, shoot the rifle as-is before you start changing the throat. I'd leave it alone until, and if, I found that the present throat would not allow me to shoot long heavy bullets without having the bullets seated too deeply. Most likely, that's why your gunsmith is hinting at a longer throat. And unless your rifling twist is faster than the traditional 22-250's rate of 1 in 14, you won't be shooting those long bullets anyway, but I'm guessing you know that.
 
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