Time to make the donuts....

[jackieschmidt]

I do not check my finished bullets for straightness. I measure the shank and base with a “tenth” micrometer, and I measure the ogive to base at a pre determined point to confirm that the bullets are what has proven to shoot well in my barrel load combination.

I trust that with my lubing techniques and attention to detail, my dies are making a straight and truly round bullet.
to anybody wishing to make their own precision Benchrest Bullets, the key is to listen to start with the very best in equipment, mainly the dies. The rest is listening to those with experience and learn. After a learning curve, and you gain knowledge of exactly how your components are are working together, you can tweak a few things to optimize your expectations.

Then you head to the range. That is when you really find out out if your efforts are as they should be.

Out of curiosity, (since I have 45,000 of them), I made a 30 caliber mandrel to use on my little jacket checker, just to see how good or bad they are. Ed and I have been shooting the bullets made on these for going on three years.

They check pretty good.

 

[jcarpen]

Yep I sure can, figure what core seating punch you are going to use. seat core and spin seated core in spinner I start with light seating pressure just enough so it comes off the punch . check the runout of seated core then increase pressure and seat another one do not reseat the first again compare the runout to the first, do a third one with more pressure check that you will find a sweet spot where the jacket runs out the least amount you can get it to. you can keep increasing pressure and also go from good t.i.r and make it worse. it never made sense to pop a jacket and back off chances are they are seated way to much...what this all comes down to is jacket material thin soft jackets square up nice and easy with less pressure next we have the little bit thicker or harder ones they take a lot little more pressure and last we have the hard and thick ones their the ones that you just about have to pop a jacket pretty regularly plus they really dont preform the way we would want . as a side note since J4 has sold out the jacket material being used is really good as compared to what they were using...

George-Are you indicating at the lead line or also at the base? You mentioned squareness of the base, how do you check that? Do you look at anything different on a boatail? Great info here.

 

[AlNyhus]

This is a follow up to Dave Coot's post a ways back.

The punch should push the jacket into the die, not your finger.

 

[D Coots]

Welcome to the Club Al....... A boattail point up punch does a much more clean job...

Thanks for starting this thread.

Later

Dave

 

[JoeDuke]

This is a follow up to Dave Coot's post a ways back.

The punch should push the jacket into the die, not your finger.

Been there. Done that! Just not in the last week or so. But no guarantees it won't happen again.
Joe

 

[David Conder]

Try doing that with a botail punch much different results lol

 

[Mulligan]

When you consider the design of the big Lee press and the length of its handle, there is a LOT of energy focused on the tip of that punch!
Ouch!!!

Clay

 

[RGRobinett]

I do not check my finished bullets for straightness. I measure the shank and base with a “tenth” micrometer, and I measure the ogive to base at a pre determined point to confirm that the bullets are what has proven to shoot well in my barrel load combination.

I trust that with my lubing techniques and attention to detail, my dies are making a straight and truly round bullet.
to anybody wishing to make their own precision Benchrest Bullets, the key is to listen to start with the very best in equipment, mainly the dies. The rest is listening to those with experience and learn. After a learning curve, and you gain knowledge of exactly how your components are are working together, you can tweak a few things to optimize your expectations.

Then you head to the range. That is when you really find out out if your efforts are as they should be.

Out of curiosity, (since I have 45,000 of them), I made a 30 caliber mandrel to use on my little jacket checker, just to see how good or bad they are. Ed and I have been shooting the bullets made on these for going on three years.

They check pretty good.View attachment 1625813View attachment 1625814View attachment 1625818

Jackie, at that DATUM area (you're measuring roughly mid-way into the tapered section) < 0.0007" variation in wall-thickness, according to my OLD SpiveCo, Inc. prints, is within J4 specification for .925" long jackets, at about 0.780" above the base. The < 0.0003"is specified at 0.150" from the inside-base.
RG

 

[David Conder]

who makes the new j4 jackets

 

[RGRobinett]

who makes the new j4 jackets

CAPSTONE PRECISION GROUP.
RG

 

[David Conder]

Do you think capstone is a better jacket then spiveco thanks ps what do you think
about stamoy I just bought 10000 .790 length thanks

 

[D Coots]

George's TIR tool. One end of rod for core seated jacket and other for finished bullet.

 

[geo.ulrich]

Jackie, at that DATUM area (you're measuring roughly mid-way into the tapered section) < 0.0007" variation in wall-thickness, according to my OLD SpiveCo, Inc. prints, is within J4 specification for .925" long jackets, at about 0.780" above the base. The < 0.0003"is specified at 0.150" from the inside-base.
RG

Randy thanks I was going to down load their print you saved me the headache of looking for it

 

[jackieschmidt]

Jackie, at that DATUM area (you're measuring roughly mid-way into the tapered section) < 0.0007" variation in wall-thickness, according to my OLD SpiveCo, Inc. prints, is within J4 specification for .925" long jackets, at about 0.780" above the base. The < 0.0003"is specified at 0.150" from the inside-base.
RG

I will check a few up there at.150 from the internal base.

some years back, I got a big lecture from a famous 22 PPC Short Shooter about why a 30 cal could never shoot at the same level of precision as a 22. He said since nobody could make a perfect jacket, the 22 would always have the advantage since the “out of balance” was closer to the center of rotation in the smaller diameter bullet.

But Like you used to say in your ByLine…….‘That’ll Never Work”

 

[geo.ulrich]

I will check a few up there at.150 from the internal base.

some years back, I got a big lecture from a famous 22 PPC Short Shooter about why a 30 cal could never shoot at the same level of precision as a 22. He said since nobody could make a perfect jacket, the 22 would always have the advantage since the “out of balance” was closer to the center of rotation in the smaller diameter bullet.

But Like you used to say in your ByLine…….‘That’ll Never Work”

But the 30 is spinning slower kind of kills that statement

 

[jackieschmidt]

Randy, I moved my indicator stylus back to about .150 from the base, and they are better. I checked 10 jackets out of the lot I have and this is what they look like.

These are those jackets that I bought out of Ronnie Cheeks last order.

 

[Fuj]

When you consider the design of the big Lee press and the length of its handle, there is a LOT of energy focused on the tip of that punch!
Ouch!!!

Clay

In old country we would say "dumb shitsky" and go for vodka......

 

[RGRobinett]

But the 30 is spinning slower kind of kills that statement

Th

I will check a few up there at.150 from the internal base.

some years back, I got a big lecture from a famous 22 PPC Short Shooter about why a 30 cal could never shoot at the same level of precision as a 22. He said since nobody could make a perfect jacket, the 22 would always have the advantage since the “out of balance” was closer to the center of rotation in the smaller diameter bullet.

But Like you used to say in your ByLine…….‘That’ll Never Work”

Per George's comment (post # 395), this is a common misconception. Actually, presuming identical wall-thickness variation, a thirty caliber bullet, is capable of greater precision than a smaller caliber: the percentage of Cg off-set is far less!! Further, all of that additional mass is more stable at substantially lower RPM.

Not factoring for velocity, but just twist rate, and comparing a 68 Gr. 6mm bullet (.850" long), via 1:13.5" twist, to a 1:18"" twist 30 Cal., the 30 lobs 118 Gr. bullets (1.01" long) at a whopping 25% LOWER RPM, producing > Sg 1.4, while the 6mm is still short of Sg1.4 (at 3500 FPSwould produce about Sg 1.3), which is needed to damp the yaw & pitch - "put the bullet to sleep".

The sole negative attribute of a thirty caliber bullet is recoil - the management thereof. RG

 

[RGRobinett]

Randy, I moved my indicator stylus back to about .150 from the base, and they are better. I checked 10 jackets out of the lot I have and this is what they look like.

These are those jackets that I bought out of Ronnie Cheeks last order.View attachment 1626171View attachment 1626172

Over a LONG haul now, J4 jackets have usually run < 0.0002" wall-thickness variation, and only occasionally greater. This is displaying about average variation.

I have not had jackets assayed for about a decade now - a cousin, involved in that type of stuff, used to do that for me: J4 jackets from both the SpiveCO, Inc., and Carann (sp?), Inc. always assayed between 90-92% Cu, & 8 to 10 percent zinc: eg., 92:8; 90:10 , while Sierra were always 95:5. Hypothetically, the 95:5 ratio is [so called] gilding metal suitable for bullet jackets. I believe that the defunct Hines jackets were of the latter ratio.

Over time, when I have received 0.0003" jackets, and stewed, lost sleep, etc., but, HAD to use the MAXIMUM in tolerance stuff, there is ONE common thread . . . after shipping bullets and sweating it out, the phone begins ringing - "do you have any more of THOSE jackets, they're the best bullets I've ever had". . . . It's the same as with every lot, including the 0.0001" Lots ("precious ones"): as George has always argued (as in argument and persuasion), there's more to precision bullet performance than meets the eye.

Regarding [BR quality] bullets, if you, and/or, your bullet maker keeps his head out of dark recesses, most of what we fret over is, "LOST IN THE NOISE". Check your ego at the door. Keep 'em ON the X! RG

 

[geo.ulrich]

Over a LONG haul now, J4 jackets have usually run < 0.0002" wall-thickness variation, and only occasionally greater. This is displaying about average variation.

I have not had jackets assayed for about a decade now - a cousin, involved in that type of stuff, used to do that for me: J4 jackets from both the SpiveCO, Inc., and Carann (sp?), Inc. always assayed between 90-92% Cu, & 8 to 10 percent zinc: eg., 92:8; 90:10 , while Sierra were always 95:5. Hypothetically, the 95:5 ratio is [so called] gilding metal suitable for bullet jackets. I believe that the defunct Hines jackets were of the latter ratio.

Over time, when I have received 0.0003" jackets, and stewed, lost sleep, etc., but, HAD to use the MAXIMUM in tolerance stuff, there is ONE common thread . . . after shipping bullets and sweating it out, the phone begins ringing - "do you have any more of THOSE jackets, they're the best bullets I've ever had". . . . It's the same as with every lot, including the 0.0001" Lots ("precious ones"): as George has always argued (as in argument and persuasion), there's more to precision bullet performance than meets the eye.

Regarding [BR quality] bullets, if you, and/or, your bullet maker keeps his head out of dark recesses, most of what we fret over is, "LOST IN THE NOISE". Check your ego at the door. Keep 'em ON the X! RG

Randy if I recall correctly you had some way worse and had the same results....