Proper way to use a rifle micrometer seating die - Page 2

hounddawg · February 23, 2019, 08:58 AM

Quote:

my .223 it does get a noticeable dent around the bullet where the stem makes contact. I may have to have a custom stem made for those bullets since they still shoot 1/2-3/4 MOA in my .223.
jetinteriorguy is offline

the seating die has to touch the bullet someplace, if it is a noticeable dent you can adjust the Lee neck die for less neck tension but if they are shooting well why bother. When that bullet exits the barrel it is not near as pretty as it went in.

http://forum.accurateshooter.com/thr...#post-36644901

**Unclenick** · February 25, 2019, 10:53 AM

Quote:

Originally Posted by USSR

Well, Nick, I use the very same seating die. The problem I've found is the seating stem makes contact with the bullet ogive well above the part of the bullet ogive that the comparator and the barrel lands makes contact with, and the variations between these 2 points on the bullet ogive show up in the CBTO measurements. I'm afraid we are going to have to agree to disagree on this one my friend.

Nothing to agree or disagree about. Measurements are whatever they are. I am very surprised by what you are reporting, though. In addition to the 150-grain SMK example, for which the Sinclair and Hornady comparators made contact 0.144" apart on the ogive, I've never seen base-to-ogive with more than about 0.002" variance seating MatchKings into .223.

You got my curiosity up. I grabbed the first box of bullets off the end of a shelf that turned out to be an old box of Hornady .308 178-grain A-max bullets. I measured base-to-ogive with the Sinclair 30 cal comparator insert, then, to simulate a high seater stem contact point, I remeasured them in the same order with the 22 cal insert. This produced a mean ogive contact height difference of 0.3358". The result was an extreme spread variation of 0.0025" with an SD of 0.00068". I repeated with a box of 175-grain SMK's and got an extreme spread of 0.003" difference in that height with an SD of 0.00072'.

So, for whatever reason, you saw a lot more variation than I've found normal for SMK's. Maybe you got a bad box? You could probably call Sierra and ask if what you got was within their normal tolerance range (if you haven't already).

Jetinteriorguy,

If you have a smaller caliber bullet comparator insert than for the bullet you are looking at in this instance, you could look to see if your bullets have that much variation by doing what I did. If not, something else is accounting for the variation you are getting. But if it is the bullets, you can sort them this way before loading, if you like.

jetinteriorguy · February 26, 2019, 05:55 AM

Good thought UN, it may just be some bad bullets. I'll have to check this out.

**Unclenick** · February 28, 2019, 05:51 PM

Yes. As Don said, the bullets are a mix that comes off different tooling. As a result, Bryan Litz said he's seen up to 3% variation in BC in the same box of match bullets, so it is possible and I don't doubt Don saw what he did for that reason (as well as taking his word for it, as he seems to be a good fellow). I expect the bare dies are cut with the same reamers, but they go through lapping and polishing, so they can shift a bit. So give it a measure and see what you get. I'd be interested to know the result.

jetinteriorguy · February 28, 2019, 07:37 PM

I'll put it on the list for this weekend. I shot 20 rounds yesterday using the method of seating long and working down to the desired seating depth. The results are promising shooting 4 groups of five shots. The first group was right at 1" with a very cold barrel. The second group was 1/4" for four and a flier taking it to 3/4", the third group was 5/16" for four rounds and of course my flier(rrrrr') making it 3/4" once,again. The fourth group was a loss, I was trying a different approach to the two stage trigger and it definitely didn't work. This is my first rifle with a two stage trigger so I'm still getting used to it.

hounddawg · February 28, 2019, 10:19 PM

Quote:

I'll put it on the list for this weekend. I shot 20 rounds yesterday using the method of seating long and working down to the desired seating depth. The results are promising shooting 4 groups of five shots. The first group was right at 1" with a very cold barrel. The second group was 1/4" for four and a flier taking it to 3/4", the third group was 5/16" for four rounds and of course my flier(rrrrr') making it 3/4" once,again. The fourth group was a loss, I was trying a different approach to the two stage trigger and it definitely didn't work. This is my first rifle with a two stage trigger so I'm still getting used to it

Most of the time a string of 5th shot flyers is not the gun or the ammo. Five bucks says you are tensing up on the 5th shot mentally and physically. You have a four round bughole and your mental sphincter tightens up on the fifth shot and get a flyer. Try some 25 round dot drills instead of groups. Boring as heck but great training.

jetinteriorguy · March 1, 2019, 05:27 AM

No doubt about that. But at least I feel like I've pretty much eliminated ammo and rifle as a problem. This is really what I've been striving to achieve, and now it's time to work on me. It's a good feeling.

F. Guffey · March 1, 2019, 08:54 AM

I had 2 300 Winchester mags, both new. One shot like a shotgun, it shot patterns and the other shot one hole groups after 74 rounds. Winchester told me to run another 100 rounds through the Model 70

.

I told Winchester the chamber was one of the ugliest chambers I have ever seen, I informed them the chamber was too long from the shoulder to the bolt face, I told them the diameter of the chamber was too large and the chamber finish was gouged.

They instructed me to take the rifle to their warranty man, I asked them about the remedy. They said they would instruct him to hone, ream and polish the chamber' and then I asked which one of those remedies was going to reduce the diameter, shorten the length of the chamber and remove the gouges without increasing the diameter of the chamber?

I attempted to pick-up the rifle at the warranty shop, they informed me they returned the rifle, I ask why; they said the chamber was to large, long and ugly. I asked them what caused that? Was it their attempt to hone, ream and or polish? they answered no and then claimed it came into the shop that way.

The other rifle? It still shoots one hole groups but it does not get to go as often. I built a 7mm57 and a 270 for the owner and now the 270 does not get to go.

F. Guffey

jetinteriorguy · March 3, 2019, 07:12 AM

So I measured a bunch of bullets yesterday and was pleasantly surprised by the results. They didn't vary by more than .003" and almost all were within .002". I have figured one thing out though, not all of my brass has been run through my rifle yet being range brass. They are all the same head stamp, necks turned to the same thickness, and trimmed to the same length. I think what's happening is even though sized on the same Lee collet neck sizing die, some of them are just tighter and have more resistance when being seated. Some are so tight it's causing the seating stem to slightly deform the bullet instead of seating deeper. This is what's causing me to sometimes really have to keep going deeper and deeper with the seating stem on some rounds in order to get to the desired CBTO depth. Today if I get time I'm going to load up some rounds just using brass that I know has been fired in my rifle and see if I get more consistent results.

**Unclenick** · March 3, 2019, 10:53 AM

I think you've found your problem. Neck sizing-only is an advantage only on brass that has been previously fired in your own chamber because you then know the body fits your chamber correctly. Normal practice with range pickups is to full-length resize (always done before trimming because full-length resizing is what grows the neck) before your first firing of them, and then neck-size-only after that firing. Once you are neck-sizing-only, then you will find a case doesn't grow appreciably unless or until it tightens enough to require another round of full-length resizing to continue using it.

If, in addition to the collet die, you have a Redding Body Die, you can do full-length resizing in that before using the collet die. But I don't think you can expect maximum consistency of head-to-ogive until after that first firing in your chamber as cases ejected by different chambers won't spring back by exactly equal amounts coming out of the resizing die until you do.

Don Fischer · March 3, 2019, 11:11 AM

Could be that even though the measurement come's out different now and then, they are all the same. Just depend's on if your measuring to the ogive to set up and then to the tip of the bullet to check. Distance from the ogive to the tip of the bullet can vary but from the head to the ogive should never vary. From the head to the tip can vary! What is important to me is that the round chamber's the same every time!

**Unclenick** · March 3, 2019, 12:02 PM

When you say "head", do you mean the base (bottom end with the bullet sitting tip-up on a surface) of the bullet? Sorry for the confusion, but "head" is a common synonym for "bullet".

Jetinteriorguy is measuring the finished cartridge from the bottom of the case head to the bullet comparator's contact point on the bullet ogive. That's what has been varying for him. He's not measuring to the tip. All the measurements of the bullet from the bottom to the ogive show between 0.002" and 0.003" extreme variation, likely due to different tooling output. Between low on the ogive (where it meets the rifling) to high on the ogive where a lot of seating stems would make contact also had that much variation (variation in ogive profile). The tip turned out not to be involved in any of the measurements.

AVirginian · March 4, 2019, 11:20 AM

I have started using Redding's Instant Indicator. I can measure both shoulder to base or ogive to base, the latter using neck sizing bushings which are far more accurate than Hornady's Comparator (I have one of those too). It is also much faster as it is used in a press but they do come with a Range Adapter that allows for use in the field or if you don't want to use it in a press. I have found that my settings off the lands is much more accurate and my groups have gotten smaller. Consistency is the name of the game.

**Unclenick** · March 4, 2019, 11:58 AM

Yep. I've suggested that in posts here before. However you do it, that measurement is what determines how far off the lands the bullet will actually be with the case forward in the chamber.

February 28, 2019, 05:51 PM	#29
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,063	Yes. As Don said, the bullets are a mix that comes off different tooling. As a result, Bryan Litz said he's seen up to 3% variation in BC in the same box of match bullets, so it is possible and I don't doubt Don saw what he did for that reason (as well as taking his word for it, as he seems to be a good fellow). I expect the bare dies are cut with the same reamers, but they go through lapping and polishing, so they can shift a bit. So give it a measure and see what you get. I'd be interested to know the result. __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle

March 1, 2019, 08:54 AM	#33
F. Guffey Senior Member Join Date: July 18, 2008 Posts: 7,249	I had 2 300 Winchester mags, both new. One shot like a shotgun, it shot patterns and the other shot one hole groups after 74 rounds. Winchester told me to run another 100 rounds through the Model 70. I told Winchester the chamber was one of the ugliest chambers I have ever seen, I informed them the chamber was too long from the shoulder to the bolt face, I told them the diameter of the chamber was too large and the chamber finish was gouged. They instructed me to take the rifle to their warranty man, I asked them about the remedy. They said they would instruct him to hone, ream and polish the chamber' and then I asked which one of those remedies was going to reduce the diameter, shorten the length of the chamber and remove the gouges without increasing the diameter of the chamber? I attempted to pick-up the rifle at the warranty shop, they informed me they returned the rifle, I ask why; they said the chamber was to large, long and ugly. I asked them what caused that? Was it their attempt to hone, ream and or polish? they answered no and then claimed it came into the shop that way. The other rifle? It still shoots one hole groups but it does not get to go as often. I built a 7mm57 and a 270 for the owner and now the 270 does not get to go. F. Guffey

March 3, 2019, 10:53 AM	#35
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,063	I think you've found your problem. Neck sizing-only is an advantage only on brass that has been previously fired in your own chamber because you then know the body fits your chamber correctly. Normal practice with range pickups is to full-length resize (always done before trimming because full-length resizing is what grows the neck) before your first firing of them, and then neck-size-only after that firing. Once you are neck-sizing-only, then you will find a case doesn't grow appreciably unless or until it tightens enough to require another round of full-length resizing to continue using it. If, in addition to the collet die, you have a Redding Body Die, you can do full-length resizing in that before using the collet die. But I don't think you can expect maximum consistency of head-to-ogive until after that first firing in your chamber as cases ejected by different chambers won't spring back by exactly equal amounts coming out of the resizing die until you do. __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle

March 3, 2019, 12:02 PM	#37
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,063	When you say "head", do you mean the base (bottom end with the bullet sitting tip-up on a surface) of the bullet? Sorry for the confusion, but "head" is a common synonym for "bullet". Jetinteriorguy is measuring the finished cartridge from the bottom of the case head to the bullet comparator's contact point on the bullet ogive. That's what has been varying for him. He's not measuring to the tip. All the measurements of the bullet from the bottom to the ogive show between 0.002" and 0.003" extreme variation, likely due to different tooling output. Between low on the ogive (where it meets the rifling) to high on the ogive where a lot of seating stems would make contact also had that much variation (variation in ogive profile). The tip turned out not to be involved in any of the measurements. __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle

March 4, 2019, 11:58 AM	#39
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,063	Yep. I've suggested that in posts here before. However you do it, that measurement is what determines how far off the lands the bullet will actually be with the case forward in the chamber. __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle

February 26, 2019, 05:55 AM	#28
jetinteriorguy Senior Member Join Date: April 28, 2013 Posts: 3,176	Good thought UN, it may just be some bad bullets. I'll have to check this out.

February 28, 2019, 07:37 PM	#30
jetinteriorguy Senior Member Join Date: April 28, 2013 Posts: 3,176	I'll put it on the list for this weekend. I shot 20 rounds yesterday using the method of seating long and working down to the desired seating depth. The results are promising shooting 4 groups of five shots. The first group was right at 1" with a very cold barrel. The second group was 1/4" for four and a flier taking it to 3/4", the third group was 5/16" for four rounds and of course my flier(rrrrr') making it 3/4" once,again. The fourth group was a loss, I was trying a different approach to the two stage trigger and it definitely didn't work. This is my first rifle with a two stage trigger so I'm still getting used to it.

March 1, 2019, 05:27 AM	#32
jetinteriorguy Senior Member Join Date: April 28, 2013 Posts: 3,176	No doubt about that. But at least I feel like I've pretty much eliminated ammo and rifle as a problem. This is really what I've been striving to achieve, and now it's time to work on me. It's a good feeling.

March 3, 2019, 07:12 AM	#34
jetinteriorguy Senior Member Join Date: April 28, 2013 Posts: 3,176	So I measured a bunch of bullets yesterday and was pleasantly surprised by the results. They didn't vary by more than .003" and almost all were within .002". I have figured one thing out though, not all of my brass has been run through my rifle yet being range brass. They are all the same head stamp, necks turned to the same thickness, and trimmed to the same length. I think what's happening is even though sized on the same Lee collet neck sizing die, some of them are just tighter and have more resistance when being seated. Some are so tight it's causing the seating stem to slightly deform the bullet instead of seating deeper. This is what's causing me to sometimes really have to keep going deeper and deeper with the seating stem on some rounds in order to get to the desired CBTO depth. Today if I get time I'm going to load up some rounds just using brass that I know has been fired in my rifle and see if I get more consistent results.

March 3, 2019, 11:11 AM	#36
Don Fischer Senior Member Join Date: March 2, 2017 Posts: 1,868	Could be that even though the measurement come's out different now and then, they are all the same. Just depend's on if your measuring to the ogive to set up and then to the tip of the bullet to check. Distance from the ogive to the tip of the bullet can vary but from the head to the ogive should never vary. From the head to the tip can vary! What is important to me is that the round chamber's the same every time!

March 4, 2019, 11:20 AM	#38
AVirginian Senior Member Join Date: February 6, 2014 Posts: 128	I have started using Redding's Instant Indicator. I can measure both shoulder to base or ogive to base, the latter using neck sizing bushings which are far more accurate than Hornady's Comparator (I have one of those too). It is also much faster as it is used in a press but they do come with a Range Adapter that allows for use in the field or if you don't want to use it in a press. I have found that my settings off the lands is much more accurate and my groups have gotten smaller. Consistency is the name of the game.