338 Edge Coal

[trueblue]

A question for those reloading for the 338 EDGE. Which Wyatt mag box are you using, the staggered feed which allows COAL of about 3.850 max, or the center feed which allows COAL of 3.995 max ? Going to shoot 300gr MK and it seems the center feed would seat the boattail closer to the neck shoulder junction at a COAL of 3.995. How important is it to not seat to much of the bullet deep into the case with these longer bullets ? Also, would it be better to just go to single feed the cartridge and seat the bullet off the lands for the best accuracy and not worry about OAL ?

[Varminator 911]

I'm thinking of having an Edge built. And just got my hands on some of the 265 and 280 gn Al tipped bullets out of Georgia. The Bullets are 1.789 and 1.853 inches long. To seat these at the neck/shoulder junction I'm coming up with about 4.07 and 4.15 COL. I could be off 0.01 or 0.02 as the only case I have to look at is a 300RUM. This still leaves about 0.2 inches of boatail below the shoulder. So if you are limited to less than 4 inches COL, there will be a fair amount of bullet in the case.

How do these numbers compare to the 300 SMK?

Sorry I cann't answer your question but thought you might be interested in these bullets as well.

[trueblue]

My #'s compare about the same with the 300MK. COAL of roughly 4.00 + with the bottom of boattail bullet at the shoulder/body junction. That was the reason for the original question: use a centerfeed Wyatt magbox which would allow 3.995 COAL or go with a single feed and have more flexibility on COAL ?

[Varminator 911]

Seating the bullet back 0.2 into the case probably won't cost more than 50fps. But that is just a guess on my part based on some data posted recently on that subject. But 50 fps adds 50yds or so to the range of your rig, at least energy wise, not wind drift. If I'm going to build a rig it will allow seating the bullet all the way out with only the boattail into the case. I can live with a single shot if need be. Doesn't sound like either of your choices will allow seating the bullet out where I'd want it. At least not with the bullets I have.

I'm more concerned about getting the throat set up right so the bullet will be the right distance from the lands.

[trueblue]

Varminator911,

Briefly explain what you mean by " setting the throat up right ". I have only seen schematics on 2-338 edge reamers and they both looked the same except for shoulder angle. I am not a gunsmith, so I would like to know what you are refering to.

[Varminator 911]

The new Al tipped and some other bullets are pretty long. Even longer than the 300SMK. Of course it's not just the bullet lenght/COL but the bearing surface that is outside the case that is of concern. So I'm thinking that the throat might have to have a little freebore if one is both going to get the right distance from the lands for accuracy while still keeping as much of the bullet out of the case as is appropriate.

In this regard, the Weatherbys are famous for their freebore. Does anyone know how much the freebore is? If one bought a 338/378 Weatherby would that amount of freebore be about right for a really long bullet to be near the lands? The bearing surface on the 280gn Al is about 0.7 inches long as well as I can measure. So if 0.3 were in the neck, that would leave about 0.4 inches outside. Is that more than a typical 300SMK setup?

Thank you!