7mm stw dies?

[hoytaddict]

I'm having some seating depth inconsistencies with my RCBS 7mm stw dies. I'll set it with a dummy round, and start loading while measuring everyone with a caliper and comparator. Out of 10 rounds I'll get 2-3 thousandths difference in them. Could the VLD's I'm loading be bottoming out in the plug? If so what brand dies would you guys recommend?

 

[boomtube]

"Out of 10 rounds I'll get 2-3 thousandths difference in them. "

Nothing wrong with your dies, that's about as 'precise' as it gets.

 

[hoytaddict]

Even if I were to step up to something like the redding dies with the VLD micrometer?

 

[frequent misser]

Yes. The difference is in your bullets. You can either sort your bullets by length or you can use a micrometer seater and seat all your bullets about .004 long. Measure the round and adjust your seater and finish seating the bullet so they are all the same. You will then have to back off the seater again and seat your next one long and measure and adjust.....You get the idea. It doesn't seem to matter what brand of vld's you shoot either. There is just a variance of a few thousandths in all of them. Either sort them or get the micrometer. I have reddings and forsters micrometer seaters and both work well. The knob is larger on the forster if that matters to you. Redding offers a micrometer for their regular seater die, rcbs may offer that as well but I don't know.

 

[frequent misser]

Yes. The difference is in your bullets. You can either sort your bullets by length or you can use a micrometer seater and seat all your bullets about .004 long. Measure the round and adjust your seater and finish seating the bullet so they are all the same. You will then have to back off the seater again and seat your next one long and measure and adjust.....You get the idea. It doesn't seem to matter what brand of vld's you shoot either. There is just a variance of a few thousandths in all of them. Either sort them or get the micrometer. I have reddings and forsters micrometer seaters and both work well. The knob is larger on the forster if that matters to you. Redding offers a micrometer top for their regular seater die, rcbs may offer that as well but I don't know.

 

[Derek M.]

you can use a micrometer seater and seat all your bullets about .004 long. Measure the round and adjust your seater and finish seating the bullet so they are all the same. You will then have to back off the seater again and seat your next one long and measure and adjust.

That's what I do.

 

[boomtube]

" Measure the round and adjust your seater and finish seating the bullet so they are all the same. "

Do you really believe a firearm cares where a bullet point hangs in empty space?

Micrometer seater heads are only user convienences for setting seating length, they add absolutely nothing to the consistancy of the OAL.

 

[frequent misser]

" Measure the round and adjust your seater and finish seating the bullet so they are all the same. "

Do you really believe a firearm cares where a bullet point hangs in empty space?

Micrometer seater heads are only user convienences for setting seating length, they add absolutely nothing to the consistancy of the OAL.

Micrometers are for user convienence but he did say he was using a comparator so he is measuring off the ogave and not the tip. If you are only seating a couple of thousandths off the lands in a hunting rig and you get a long one and jam it and cant get it out your screwed. Inside of 1000 yards it probably doesn't make much difference but shoot groups on paper at that range or farther and I bet you see it in your vertical. In my 308 with 155's I just set up my seater and roll with it. In my 300 wsm and stw I make sure they are all the same.

 

[sambo3006]

Isn't the important factor the over all length of the cartridge to the front of the bullet bearing surface? That is the only part of the bullet that contacts the barrel. The tips of VLD bullets are not very consistent and if you adjust each round to achieve the same OAL you are making inconsistent rounds as far as the overall length from cartridge base to bearing surface. That is of course assuming that the bullets have a consistent length of bearing surface.
My take is that I leave the die where it is and try to seat all rounds with consistent press stroke and not worry about small differences in OAL. I'm no expert or competetive shooter, just my two cents. Maybe some experts can chime in.

 

[hoytaddict]

That's the problem. I'm not measuring OAL, I'm using a comparator measuring off the ogive. That's why I think the points are bottoming out in te seating plug

 

[boomtube]

"I'm using a comparator measuring off the ogive."

Even so, a varitation of only 2 thou is about as precise as it gets. Varing pressure on the press will do that much, ditto differences in "bullet tension."

IF we got all our bullets off a single machine with the same forming dies they could be quite precise. Unhapply, factory bullets are made on mulitpule machines and with different dies, the resulting ogive curvature itself will easily cause 2 thou of variation.


"That's why I think the points are bottoming out in te seating plug "

Maybe,... but I doubt it.

Anyway, you're swatting at gnats, not buzzards; no factory rifle shooting factory bullets will ever show a difference on target with the tiny seating variation you're getting. Most of the rifles I've loaded for over the last 45+ years have a good shooting seating depth 'window' as much as 15 thou wide in which there's no difference at all on target and that's especially true for cartridges as large as yours. If your accuracy isn't good it's not because of 2 thou of seating differences.

 

[7stw]

That's the problem. I'm not measuring OAL, I'm using a comparator measuring off the ogive. That's why I think the points are bottoming out in te seating plug

I think that is your problem , and that would explain the difference with your comparator. These bullets do need a little more of a spacious seater plug. I am using a RCBS comp seater and having no problems with my STW, but have had issues like yours in other calibers. Redding makes special seaters FOR VLD bullets. I have a set for my 300 ultra, they work great. That STW is the best ride you will ever have. Love mine. AIM SMALL, MISS SMALL.lightbulblightbulbgun) 7STW

 

[frequent misser]

"I'm using a comparator measuring off the ogive."

"That's why I think the points are bottoming out in te seating plug "

Maybe,... but I doubt it.

Anyway, you're swatting at gnats, not buzzards; no factory rifle shooting factory bullets will ever show a difference on target with the tiny seating variation you're getting. Most of the rifles I've loaded for over the last 45+ years have a good shooting seating depth 'window' as much as 15 thou wide in which there's no difference at all on target and that's especially true for cartridges as large as yours. If your accuracy isn't good it's not because of 2 thou of seating differences.

Boomtube I am inclined to agree with you and the difference it would make would be nearly impossible to really measure and verify. I just think if its a variable I can control with another couple of minutes at the reloading bench that might help with velocity spread then I might as well do it. I need all the help I can get beyond 1k. That said I don't bother worrying about it in my factory guns either. If I had something other than a crappy shooting chrony I don't believe half the time I would load some up with .003 difference and measure.

 

[boomtube]

I just think if its a variable I can control with another couple of minutes at the reloading bench that might help with velocity spread then I might as well do it.

A good goal but I wonder if it's possible to accomplish; even the best of cases aren't made with the precision of a watch. I have no 1000 yard range or experience but I suspect the percentage of internal volume differences between individual cases will exceed the volume change induced with a seating variation of 2-3 thou, especially in such huge cases.