bushing size for 6.5 cm
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Re: bushing size for 6.5 cm
Well here are my numbers for .260 rem
0.265
0.013
0.013
----
0.291 -0.002 for neck tension would give about 0.289
Don't go on that, wait for someone with Hornady brass as the neck wall might be thicker or thinner than my Remington.
Well here are my numbers for .260 rem
0.265
0.013
0.013
----
0.291 -0.002 for neck tension would give about 0.289
Don't go on that, wait for someone with Hornady brass as the neck wall might be thicker or thinner than my Remington.
Re: bushing size for 6.5 cm
I got the Redding .286 and .287 for Norma and Nosler brass... but it's for a .260Rem.
I got the Redding .286 and .287 for Norma and Nosler brass... but it's for a .260Rem.
Re: bushing size for 6.5 cm
<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">hornady 6.5 <span style="font-weight: bold">cm</span> brass? </div></div>
2.54 cm = 1 inch
so 6.5 cm = 2.559 inches!!
..not to be facetious....but I think you mean 6.5mm
as for the bushing sizing....a lot of guys recommend 0.002" neck tension....but BE CAREFUL......neck wall thickness will greatly vary your actual neck "tension"...
<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">There is no "best" -- some guns/cartridges work well with .001 neck tension, some others need more... maybe a lot more.
But here's a suggestion that may help put things in perspective. Think in terms of overall bullet "grip" instead of just bushing size.
Bullet grip is affected by many things, such as
1. Neck-wall thickness
2. Amount of bearing surface (shank) in the neck
3. Surface condition inside of neck (carbon can act as a lubricant; ultrasonic cleaning makes necks "grabby")
4. The springiness of the brass (which is related to degree of work-hardening; # of firings; time between annealings)
5. Time during which the loaded round has sat prior to firing
--and there are others...
You can do this simple experiment. Seat a boattail bullet in your sized neck with .150" of bearing surface (shank) in the neck. Now remove the bullet with an impact hammer. Next, take another identical bullet and seat it with .300" of bearing surface in another sized case (same nominal tension). You'll find the deeper-seated bullet is gripped much harder.
I have also found that thinner necks, particularly the very thin necks used by short-range benchresters, require more sizing to give equivalent "grip". Again, do your own experiment. Seat a bullet in a case turned to .008 neckwall thickness and sized down .003. Now compare that to a case with .014 neckwall thickness and sized down .001. You may find that the bullet in the thin necks actually pulls out easier, though it supposedly has more "neck tension" based on bushing size.
<span style="font-weight: bold">This use of the term "neck tension" when we are really only describing the amount of neck diameter reduction with a die/bushing is really kind of inaccurate.
We don't have any easy way to measure "true" neck tension on a bullet.
</span>
My point here is that it is overly simplistic to ask, should I load with .001" tension or .003". In reality, an .001" reduction on a thick neck might provide as much or MORE "grip" on a long bullet than an .003" reduction on a very thin-walled case on a short shank.
What I think this means... and this is only a theory... is that I suspect the guys using .001" "tension" on no-turn brass may be a lot closer to the guys using .003" "tension" on turned necks than either group may realize.
This doesn't really provide any answers. You have to go out and test empirically to see what works, in YOUR rifle, with YOUR bullets and powder. And you may have to change the nominal tension setting (i.e. bushing size) as your brass work-hardens or IF YOU CHANGE SEATING DEPTHS.
All I'm saying is that the nominal bushing size is not really a satisfactory indicator of the true amount of neck grip on a bullet, or the force required for release. TRUE GRIP () is a much more complicated phenomenon, one that is affected by numerous factors, some of which are very hard to quantify.</div></div>
<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">hornady 6.5 <span style="font-weight: bold">cm</span> brass? </div></div>
2.54 cm = 1 inch
so 6.5 cm = 2.559 inches!!
..not to be facetious....but I think you mean 6.5mm
as for the bushing sizing....a lot of guys recommend 0.002" neck tension....but BE CAREFUL......neck wall thickness will greatly vary your actual neck "tension"...
<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">There is no "best" -- some guns/cartridges work well with .001 neck tension, some others need more... maybe a lot more.
But here's a suggestion that may help put things in perspective. Think in terms of overall bullet "grip" instead of just bushing size.
Bullet grip is affected by many things, such as
1. Neck-wall thickness
2. Amount of bearing surface (shank) in the neck
3. Surface condition inside of neck (carbon can act as a lubricant; ultrasonic cleaning makes necks "grabby")
4. The springiness of the brass (which is related to degree of work-hardening; # of firings; time between annealings)
5. Time during which the loaded round has sat prior to firing
--and there are others...
You can do this simple experiment. Seat a boattail bullet in your sized neck with .150" of bearing surface (shank) in the neck. Now remove the bullet with an impact hammer. Next, take another identical bullet and seat it with .300" of bearing surface in another sized case (same nominal tension). You'll find the deeper-seated bullet is gripped much harder.
I have also found that thinner necks, particularly the very thin necks used by short-range benchresters, require more sizing to give equivalent "grip". Again, do your own experiment. Seat a bullet in a case turned to .008 neckwall thickness and sized down .003. Now compare that to a case with .014 neckwall thickness and sized down .001. You may find that the bullet in the thin necks actually pulls out easier, though it supposedly has more "neck tension" based on bushing size.
<span style="font-weight: bold">This use of the term "neck tension" when we are really only describing the amount of neck diameter reduction with a die/bushing is really kind of inaccurate.
We don't have any easy way to measure "true" neck tension on a bullet.
</span>
My point here is that it is overly simplistic to ask, should I load with .001" tension or .003". In reality, an .001" reduction on a thick neck might provide as much or MORE "grip" on a long bullet than an .003" reduction on a very thin-walled case on a short shank.
What I think this means... and this is only a theory... is that I suspect the guys using .001" "tension" on no-turn brass may be a lot closer to the guys using .003" "tension" on turned necks than either group may realize.
This doesn't really provide any answers. You have to go out and test empirically to see what works, in YOUR rifle, with YOUR bullets and powder. And you may have to change the nominal tension setting (i.e. bushing size) as your brass work-hardens or IF YOU CHANGE SEATING DEPTHS.
All I'm saying is that the nominal bushing size is not really a satisfactory indicator of the true amount of neck grip on a bullet, or the force required for release. TRUE GRIP () is a much more complicated phenomenon, one that is affected by numerous factors, some of which are very hard to quantify.</div></div>
Re: bushing size for 6.5 cm
6.5cm = 6.5 creedmoor
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 6.5WSSM</div><div class="ubbcode-body">
2.54 cm = 1 inch
so 6.5 cm = 2.559 inches!!
..not to be facetious....but I think you mean 6.5mm
</div></div>
6.5cm = 6.5 creedmoor
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 6.5WSSM</div><div class="ubbcode-body">
2.54 cm = 1 inch
so 6.5 cm = 2.559 inches!!
..not to be facetious....but I think you mean 6.5mm
</div></div>
Re: bushing size for 6.5 cm
I was able to measure some of my Hornady 6.5 creedmoor brass last night. The neck thickness varied from .015 to .016. If i get a bushing that is .002" smaller than the overall width, the bushing could vary from .292 to .294.
I was hoping someone with experience loading the 6.5 creedmoor rounds could help me select the correct bushing. I would rather not waste the money on three bushings if i can get away with one.
I didnt order the dies or bushings yet so any info would be appreciated.
Thanks,
avd
I was able to measure some of my Hornady 6.5 creedmoor brass last night. The neck thickness varied from .015 to .016. If i get a bushing that is .002" smaller than the overall width, the bushing could vary from .292 to .294.
I was hoping someone with experience loading the 6.5 creedmoor rounds could help me select the correct bushing. I would rather not waste the money on three bushings if i can get away with one.
I didnt order the dies or bushings yet so any info would be appreciated.
Thanks,
avd
Re: bushing size for 6.5 cm
I battled this. Anything less than a .288 was not enough tension for me.
I battled this. Anything less than a .288 was not enough tension for me.
Re: bushing size for 6.5 cm
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 427Cobra</div><div class="ubbcode-body">Just buy Hornady non bushing dies, there tailor made for the brass </div></div>
Do they make a non bushing die for the CM? My CM die has a bushing, and I wasn't aware there were more than one.
Is that the difference between the "competition die" set?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 427Cobra</div><div class="ubbcode-body">Just buy Hornady non bushing dies, there tailor made for the brass </div></div>
Do they make a non bushing die for the CM? My CM die has a bushing, and I wasn't aware there were more than one.
Is that the difference between the "competition die" set?
Re: bushing size for 6.5 cm
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 427Cobra</div><div class="ubbcode-body">Just buy Hornady non bushing dies, there tailor made for the brass </div></div>
+1 "F" all that bench rest crap
140 A-Max
41.5g of 4350
1/3 MOA out of a Stiller built Tac 30 rifle.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 427Cobra</div><div class="ubbcode-body">Just buy Hornady non bushing dies, there tailor made for the brass </div></div>
+1 "F" all that bench rest crap
140 A-Max
41.5g of 4350
1/3 MOA out of a Stiller built Tac 30 rifle.
Re: bushing size for 6.5 cm
I use the Standard Hornady set of dies with my 6.5 Creedmoor. No bushing. Works great. That said if you wanted a bushing size I would go with .288. My loaded measured .292, fired was .294 and when I run them through my die they come out .288 and that works great for me.
I use the Standard Hornady set of dies with my 6.5 Creedmoor. No bushing. Works great. That said if you wanted a bushing size I would go with .288. My loaded measured .292, fired was .294 and when I run them through my die they come out .288 and that works great for me.
Re: bushing size for 6.5 cm
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: avd</div><div class="ubbcode-body">I appreciate the input. I think i am going to just go with the hornady dies. </div></div>
+2
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: avd</div><div class="ubbcode-body">I appreciate the input. I think i am going to just go with the hornady dies. </div></div>
+2
