Choosing Throat Angle for 338-06 Improved

[J E Custom]

That A-Square SAAMI drawing was the one I was looking at, the one I didn't like.

I found this non-SAAMI non-A Square one that makes a lot more sense to me.

I hear you. and that is Ok It's just a difference in opinion .If you are going to shoot only the secant Ojive bullets. (the free bore is very short With that reamer design) that should work.

I like a little more diameter and close to .200 throat length for heavy loading.

The 338/06 just like the 35 Whelen can be loaded to some awesome velocities, and In My opinion need good dimensions for the free bore and throat.

Just my take on this round.

J E CUSTOM

 

[Edd]

Well back to my original question........

Is there a reason why a 338-06 would need more freebore than a 338 RUM?

 

[shortgrass]

Well back to my original question........

Is there a reason why a 338-06 would need more freebore than a 338 RUM?

The only reason I can think of is, if you don't lengthen the free bore (& throat) bullets are seated deeply into the case, taking up space that could otherwise be occupied by propellant. I used a throating reamer from Manson that had free bore incorporated in it (spiral flute) to being the loaded round length out closer to commercial Mauser specs. (3.340 mag length, 3.300 OAL cartridge w/ 250g projectile & .020" free bore before engaging the throat) Those big bullets in a /06 case, even if it's an "improved", can take up a lot of space. If you're having a reamer made a sample round makes a lot of sense.

 

[Edd]

A 338-06 has a long case neck. It is .100" longer than the bearing surface on a Berger 250 gr bullet. Unless someone tells me why I shouldn't, I am going to have a reamer made with about .140" free bore.

 

[J E Custom]

A 338-06 has a long case neck. It is .100" longer than the bearing surface on a Berger 250 gr bullet. Unless someone tells me why I shouldn't, I am going to have a reamer made with about .140" free bore.

I think It is throated long for the same reason Shortgrass stated. Also It could be because the "Older" 30/06 length actions are shorter than the new magnum actions and that would give you
ample free bore for the shorter actions.

Free bore/throat length is a personal preference and is variable to a point depending on what the person wants/expects of a cartridge.

On my heavy powder charged cartridges I have found no ill effects with free bore. In fact, I have several rifles that have over .500 free bore that will shoot groups below .100 (1/10th MOA) with huge amounts of powder and no signs of pressure.

Just My opinion

J E CUSTOM