Minimum bullet length in the neck.

Ruttinbuck

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My new to me 280AI has a long throat.
The 140gr Accubonds have .225 left in the neck when seated out to the land.I have already pretty much given up on using these bullets without setting back the barrel.What do you guys think?Is there enough bearing surface there?The 160gr Accubonds or 150gr Baltips are longer and will work,however the 140gr was gonna be my prime bullet.RB
 
Try the rifle "as-is' with the 140s and don't worry about getting close to the rifling. The practise of getting close to the rifling is an attempt to compensate for less than symmetrical cartridges. It is one of these things that everyone says "must" be done while in reality it often makes little difference in the real world.

Take care in reloading and the accuracy, even with a sizable jump to the lands, may surprise you.

As to the original question "common" wisdom says to try and maintain at least on calibre width of neck grip on the bullet. As with most things however this seldom is true. As long as you have enough grip to hold the bullet square and solid in the case it will work.
 
I think you should be fine. Isn't that just kie having a lot of freebore...which is what Weatherby does to increase velocity? My friend's 30-06 was similar, you could barely seat a 180gr TSX so that it would touch the lands. It still shot well.

BTW, the .300 Win Mag has only 0.264" of neck (for a .308" bullet), and I think it is fair to say that the number of long range competitions it has won is proof that the well known "rule of thumb" Silverback mentions may not be a rule at all.
 
I thought the "one caliber depth for neck grip" rule was just a general rule of thumb.I have lived by this rule with my other rifles,but I was a little surprized and disappointed when I saw how long the throat is on this rifle.I may have to use a flat based bullet if 140gr is gonna be the weight.RB
 
The only problem with a bullet barely in the neck would occur when handling the ammunition and when feeding it into the chamber... it certainly would make no difference once the round is fully chambered....

I have seen bullets only held in the neck by 1/8 of an inch and loaded one at a time work fine...
 
When seating Sierra 225gr bullets close to the lands in my 35 Whelen AI, the bullets had little bearing surface in the case neck so I e-mailed Sierra and they recommended the "rule of thumb". A 300 Win Mag may have a short neck but it also has 1/4" of bullet down in the case past the neck, the guys at Sierra recommended the "rule of thumb" of one caliber to prevent the possibility of bullets moving forward under recoil. In a 300 Win. Mag. the tension on the bullet is maintained by the neck on the deeply seated bullet even if it moves a bit, on a 280AI like Ruttinbuck's the tension would decrease each time if the bullet moved.
 
In lots of hunting guns - the length of the magazine is the limit factor in max. cartridge length. Over length cartridges may shoot marginally better but who wants a single shot bolt gun?
Carry on!
 
I usually want one caliber of shank contacting the neck at least

but you can at least try the 140 Accubonds seated deep, and see how that works :confused: it's worth a shot.
 
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