How much case mouth do I need gripping a bullet?

[HNDLDR]

I'm working up a load for my wife's Browning X bolt 7mm-08 using 140 GR Berger VLD's. I can touch the rifling and still fit them in the magazine. The only problem is, by my calculations, that only leaves .135" of case mouth holding on to the bullet. Are these worth trying or should I seat them deeper?

 

[DocDoc]

The usual rough "rule of thumb" is a bullet diameter.

 

[venatic]

rule of thumb is to have a minimum of bullet diameter which of course would be .284

.135 is not enough IMO for a Hunting round.... now if you are just shooting at the range thats different

 

[Mikecr]

There is no credible rule of thumb.
Hell there are cartridges that do not even provide a cal's worth of neck. No problem.
I size less than a cal's length on several cartidges. No problem.

Then again, there is no credible reason to load touching lands -unless full seating testing has shown this as best.

 

[tbrice23]

rule of thumb is to have a minimum of bullet diameter which of course would be .284

.135 is not enough IMO for a Hunting round.... now if you are just shooting at the range thats different

Whoever made up that rule has never seen or loaded for a 300 winchester magnum!
Which is one great accurate hunting cartridge.

 

[DocDoc]

.264 of neck for the 300 Win Mag. Does it work? Absolutely! Would it be better with a little longer neck, INMO Yes. I might note that the 7mm SAUM is picking up with long range shooters compared to the 7mm WSM.

 

[venatic]

There is no credible rule of thumb.
Hell there are cartridges that do not even provide a cal's worth of neck. No problem.
I size less than a cal's length on several cartidges. No problem.

Then again, there is no credible reason to load touching lands -unless full seating testing has shown this as best.

I too seat less than caliber on cartridges all the time because it's just a rule of thumb not one of the 10 Commandments. But based on what the OP said I would consider .135 of the bullet especially if its a BT bullet a possible problem for a hunting round. That's not much bullet.

 

[MagnumManiac]

.264 of neck for the 300 Win Mag. Does it work? Absolutely! Would it be better with a little longer neck, INMO Yes. I might note that the 7mm SAUM is picking up with long range shooters compared to the 7mm WSM.

Please, with all your wisdom, explain to me HOW a longer neck on the 300 Win Mag would make it a better cartridge?
I have 2 of them, one for hunting and one for 1000yrd comp. Both are superbly accurate. I also have a 300 Weatherby, it has a long neck, but isn't as consistent as the 300 Win Mag is, it is accurate most of the time, but not always.
I do not understand your thinking, long necks went out with the dinosaurs because it has been proven time and again that neck length has little influence on accuracy. As long as neck tension is sufficient and consistent, it trumps neck length any day of the week.

lightbulb

 

[HNDLDR]

The .135 is not including the .220" length of the boat tail. The bullet is .355 in the case including the boat tail.

 

[Barrelnut]

The .135 is not including the .220" length of the boat tail. The bullet is .355 in the case including the boat tail.

I too think .135 is a bit weak for a hunting cartridge. The rest of it (boat tail) is just consuming case capacity. Can you pull the bullet out with your fingers? If so, IMO, that is not good.

I shoot the VLD in 3 rifles.
6.5 Creedmoor - seat to the lans for best accuracy
300 WSM - seat to the lans for best accuracy
300 RUM - seat 20 thou off lans for best accuracy (go figure)

Did you try the Berger seating depth test they suggest? Your rifle may well shoot the VLDs off the lans. Never know unless you try.

Here's the link to the sticky
http://www.longrangehunting.com/for...accuracy-berger-vld-bullets-your-rifle-40204/

 

[HNDLDR]

I'm actually using the brass for my Remington R-25. I've loaded the VLD's in three steps of .030" from max magazine length back. This is .085" from the lands to .141 from the lands in my R-25. I just loaded 5 quick rounds to try in my wife's Browning. When she gets done emptying her own brass and I get it cleaned, trimmed and annealed, then I will do a serious load work up for her rifle.

 

[HNDLDR]

This is also my first attempt to use IMR 4166 since our favorite Varget has been completely unavailable here locally. There's obviously a lot of variables going on here and it's going to take me a while to find time to sort it all out with work and family.

 

[HNDLDR]

Groups came in at .8" at 100 yards with the Browning. It was too windy to really set up the chronograph. I think I'll go ahead and seat in steps of .040" as per Bergers recommendations. My R-25 put three into .4" at .115 off of the lands and we can't have the AR out shooting the Browning bolt.

 

[FEENIX]

Is there magic in a case's shoulder angle relative to its neck length? @ www.reloadersnest.com