bullet seating

[Jody Ward]

Thanks to all! Glad to know that others have had this issue and I'm not crazy................well may be close. I will be exercising all of the input you fellas have given me to find what works the best for me. And I dry tumble my brass.

 

[Jager]

Since there's going to be variance in every component and every process step - and those variances add up... I'd suggest taking some of that out of your bullet-seating equation: instead of measuring cartridge-base-to-ogive, measure cartridge-shoulder-to-ogive.

https://bullettipping.com/products/seating-depth-comparator/

The product page linked has an embedded 8-minute video by F-Class John demonstrating the difference between your current method and this one.

(I have no affiliation with Accuracy One).

 

[Conaso]

Since there's going to be variance in every component and every process step - and those variances add up... I'd suggest taking some of that out of your bullet-seating equation: instead of measuring cartridge-base-to-ogive, measure cartridge-shoulder-to-ogive.

https://bullettipping.com/products/seating-depth-comparator/

The product page linked has an embedded 8-minute video by F-Class John demonstrating the difference between your current method and this one.

(I have no affiliation with Accuracy One).

I've been looking at the product and was hoping to find an online manual. What does it have for the consistency at the ogive, given that it handles different calibers - #1 Body: .17-.243/6mm? Is there an imbedded insert that hits at a high point on the ogive nearer the bullet's bearing surface versus near the tip?

 

[jimmymac]

The trick for consistency with the Redding Competition Seater is do not rely on the break over of the linkage as a stop. Set it up so the shell holder comes in firm contact with the bottom of the die, giving a positive stop.

I use Redding dies exclusively in my 6PPC and 30BR.

^^^^^^This^^^^^^

Another option to help eliminate variation is to use an arbor press and appropriate die. Same principle. There is a solid stop at the bottom.

 

[Jager]

I've been looking at the product and was hoping to find an online manual. What does it have for the consistency at the ogive, given that it handles different calibers - #1 Body: .17-.243/6mm? Is there an imbedded insert that hits at a high point on the ogive nearer the bullet's bearing surface versus near the tip?

Yes, there is an embedded - not replaceable - insert that contacts the bullet along the ogive. Different bullet profiles will contact at different places along their ogive, but that doesn't matter since we're always measuring the same bullet type in any reloading session.

What I can say is that there is far less variation using this cartridge-shoulder-to-ogive measurement than there is with a conventional cartridge-base-to-ogive measurement, using calipers and comparator. It's a much more nuanced way of seeing seating depth.

 

[Charlie-NY]

I have had this happen on a few occasions. Ultimately, one of two things was determined to be the cause.

1. compressed powder
2. excess neck tension

 

[Conaso]

Thanks. I have the Hornady but the greatest variation is from me using a caliper.

 

[rwj]

The trick for consistency with the Redding Competition Seater is do not rely on the break over of the linkage as a stop. Set it up so the shell holder comes in firm contact with the bottom of the die, giving a positive stop.

I’m not following why contact between the shell holder and die body is necessary. Raising the case into the spring loaded sleeve establishes the case base/shell holder datum, the next datum is established when the seating stem contacts the bullet and micrometer ball end to set depth. What am I missing?

 

[Alexander-M]

Yes, definitely anneal after every shooting, then use these for an almost guaranteed +/- .0005" bullet seating variation:



Alex

 

[Paddyd]

I think you are likely seeing the variation in the length of the bullet between the ogive and the bullet tip (bullet OAL - BTO = OTT). I just measured 30 Sierra 116 TMKs and found a .007" variation in OTT.

Isn't he measuring base to ogive?

 

[charlie b]

I’m not following why contact between the shell holder and die body is necessary. Raising the case into the spring loaded sleeve establishes the case base/shell holder datum, the next datum is established when the seating stem contacts the bullet and micrometer ball end to set depth. What am I missing?

You are right. The seating stem is one datum. The other datum is where the shell holder is at. You can adjust it so the press linkage sets the upper limit of the shell holder. Every time you set the die in the press it will have to be at the same location.

But, if you set the die such that the shell holder contacts the die body then it is a fixed point every time. Doesn't even matter which press you use it in. Think of it like an arbor die used in your press. I set mine so the linkage does not come close to top dead center. That way I have a better feel for the neck tension and when the die bottoms out.

PS you do have to use the same shell holder each time. Differences in shell holders can cause small inconsistencies in seat depth.

 

[charlie b]

So, thinking about this type of thing....again.

When loading cast bullets I'd make a seating stem that matched the bullet nose. Usually just JB weld in the end of the stem. Reduced deformation of the bullet nose and gave really consistent seat depth. I had one cast bullet with a tapered nose that still gave me problems. I made a tapered die and ran each bullet into that die to make the taper consistent across all the bullets. Again, very consistent seat depth.

Some folks take the trouble to point their bullets. Why couldn't there be a final form die to run the bullets in to get more consistent BTO. Kinda like the hand made bullet folks do. Then make a seating stem that mimics that form.

Not sure it would make much difference in the long run given the modern bullet quality.

 

[rwj]

But, if you set the die such that the shell holder contacts the die body then it is a fixed point every time. Doesn't even matter which press you use it in. Think of it like an arbor die used in your press. I set mine so the linkage does not come close to top dead center. That way I have a better feel for the neck tension and when the die bottoms out.

I prefer to take advantage of the spring loaded sleeve allowing the press linkage to cam over. It creates two bullet seating actions at TDC on each press handle stroke.