Need some 6.5mm/.264 throat only reaming done.

jonh172

jonh172

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Anyone know who I could call to get a throat only reamed?

I have a 260 Rem chamber and picked up some 140gr custom bullets, the taper on the bullet does not allow me to seat the base past the neck/shoulder junction, as the bullet just falls in when I reach my chamberings COAL while seating.

My COAL is 2.855" with these bullets and this is just touching the lands, but at 2.870" I lose all neck tension and can just push the bullet into the case by hand.

I get great tension at 2.920" COAL, and this is perfect as the base of the bullet is exactly at the neck/shoulder junction, and I can still use my magazine, but leaves me with a 65 thou jam in the lands.

So, I'm looking to ream the throat about 65 thou. so I can use my new bullets.

I will entertain bumping the chamber up to a 260AI in the process, but for now, any leads on a smith who has a throat only reamer would be greatly appreciated.
 
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My norm is to throat so the start of the boat tail is flush with the start of the neck so you have some throat to chase as it wears. Sounds like you have a neck sizing issue if the bullets are falling into the case or you have some real wacko projectiles. Some of your numbers seem backwards?? If I am understanding right? Who made the projectiles?
 
Hi Ian,

Which numbers seem backwards?

Yes; seating the bullet so the base of the boattail is flush at the junction is what I'm trying for.

Its not a sizing issue, I've sized the case necks small (0.255") for trouble shooting and the bullet itself is opening the neck then tapers off quickly so it can't be seated too deeply, at 2.92" COAL there's great tension.

Definitely wacko bullets with some potential for high BC.
I really want to pursue this as I bought enough to keep me shooting for a while!!
 
I take it that the projectiles are falling INTO the case? I said I go for the start of the BT at the start of the neck. This means that the boat tail itself is below the neck.

You said that "2.855" with these bullets and this is just touching the lands, but at 2.870" I lose all neck tension and can just push the bullet into the case by hand. " So longer is okay and they touch but at shorter they fall into the case. So just load to 2.855, which is the longer dim. They don't need jump.

Your throat will always get longer, about when you have a good load figured out!

Guys give me lots of dummies which are wrong and if I went by them the projectiles would be falling out of the cases after a few hundred rounds. Makes for a very expensive barrel.
 
Read the above post again and think about a decision...

Possibly if they are going to be your permanent choice of bullet and the magazine will accept the length you want, then have it throated to fit that weird bullet. Normal bullets may have to jump considerably if you use them again.

Normally vld bullets have quite a taper so the barrel does not require long throating...
 
2.870" is LONGER than 2.855", I think you are reading the number backwards???
If tension allowed it, 2.870" would be a 0.015" jam.
2.870" loses all tension, I'm in no way able to make 2.855", the bullet is in the case at that point.

Also; we are saying the same thing about the boattail, I want the BT bellow the neck and the largest diameter of the base at the bottom of the neck.

Guntech:
What you said is exactly what I would like to achieve.
 
So if the start of the boat tail is at the neck/shoulder junction at a COL of 2.920 and your bullet falls into the case at 2.870 COL that would mean the bullets bearing surface is only .050 long???
That makes no sense, either your sizing wrong or the bearing surface of the bullet is tapered. If your using a collet die I would try a conventional die and see if that helps.
 
I took some measurements, in these pictures it shows how the base of the bullet is 0.264" +/- 0.0005".
As I move the base of the bullet out of the caliper the readings start to decrease about 0.050" up the bearing surface.


Exaggerated photo to show the base is being measured 0.2645"




Boattail is above but the base is still being measured here



Approximately 0.050" above the base




And just further up
 
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If that "lip" and that "body taper" is intentional it is a lousy bullet design as far as I am concerned. What does the bullet maker have to say about it?
 
guntech said:
If that "lip" and that "body taper" is intentional it is a lousy bullet design as far as I am concerned. What does the bullet maker have to say about it?
Click to expand...

Kind of a weird design to have a lip at the bottom that's clearly causing the tension issues, I just tried another full length sized case and no expander ball, so the neck ID was 0.255, that's 9 thou neck tension, and I slowly seated and checked the COAL in small increments, and at exactly 2.870" I feel that lip drop bellow the shoulder junction and then I can just push bullet into the case by hand.
I'll have to contact the maker and see what's up with these, bad batch or Intentional?
 
jonh172 said:
Kind of a weird design to have a lip at the bottom that's clearly causing the tension issues, I just tried another full length sized case and no expander ball, so the neck ID was 0.255, that's 9 thou neck tension, and I slowly seated and checked the COAL in small increments, and at exactly 2.870" I feel that lip drop bellow the shoulder junction and then I can just push bullet into the case by hand.
I'll have to contact the maker and see what's up with these, bad batch or Intentional?
Click to expand...

That "lip" problem has risen over the years with various bullet makers. Many Many years ago Terry McCracken had that problem with one of his 51 grain Benchrest bullets... he had to change one of his forming dies I think.
 
guntech said:
That "lip" problem has risen over the years with various bullet makers. Many Many years ago Terry McCracken had that problem with one of his 51 grain Benchrest bullets... he had to change one of his forming dies I think.
Click to expand...

Hmm... well this is discouraging. I'll see what he says before I do the throating.
 
guntech said:
That "lip" problem has risen over the years with various bullet makers. Many Many years ago Terry McCracken had that problem with one of his 51 grain Benchrest bullets... he had to change one of his forming dies I think.
Click to expand...

I opened up another package of them and they don't have the lip, they seat right down to 2.820" with lots of tension. So I have a box of lipped ones I guess that are maybe still good if seated long.
I'll try out these non-lipped ones in my rifle as is and see if they do well, I'll still consider throating the rifle to get more boiler room.

Thanks for all the help!
 
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