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dbern
12-19-2020, 05:06 PM
I have an old turret 1000 lee 3-hole press purchase in 1990. With carbide 9mm Sizing/Decapping; powder thru expanding die; and bullet seating dies.

The issue I am having and looking for direction on, is the bullet seating die. I set up the die to 1.141 and keep getting a variance in seating depth from 1.136 to 1.148. There's been times it's gone as high as 1.151. I have double checked the dies are setup correctly just keep having this issue. I know it's not going to stop it from going bang but . . .

I am thinking it's the knob where you set depth might be loose and moves as I reload. Think I should use nylon tape on it to tighten it up a-bit. Or is this amount of variance not a big deal and I should not worry about it.

Thought I would throw a note here to see what others think or if they have ran into this issue before.

zarrinvz24
12-19-2020, 05:21 PM
Seems like it’s probably a concentricity problem with the sizing or expander. Check to make sure the expander is not slightly cockeyed. From what I remember the expander that powder flows through is a loose fit inside the die. Another possible culprit is that you are using carbide dies, likely to avoid lubing the cases. It’s important to still lube inside the casing neck or the expander ball or bell can cause it to warp the casing slightly on the downstroke.

onelight
12-19-2020, 05:31 PM
It can vary that much sometimes from the bullets you are loading. What bullets are you using ?

Conditor22
12-19-2020, 05:55 PM
IF you don't "stroke the press" the same you can get differing OAL

dbern
12-19-2020, 06:07 PM
I am using Berry's 115 gr round. I used Hornady 115 gr round and still had the same issue.

dbern
12-19-2020, 06:14 PM
zarrinvz24; I will try lube next week when I reload again.

I usually only use lube when I decap/resize prior to cleaning the brass. Once clean, I run through the press not lubed as I feel the sizing has already been done and the expander / bullet seating does not do that much to the case. Do you think spray lube in the die or just on the brass?

Conditor22; I really make a point of going all the way up and all the way down to make sure I seat the bullet and primer all the way. I have had an issue before and noticed I was not seating the primer all the way, so I double check. Even to the point of rotating the case and stoking down again to make sure the primer is all the way in.

largom
12-19-2020, 06:36 PM
The turret has "play" between the plate and the press frame. I solved the problem on mine by placing a large washer under one of the top bolts which extends over the edge of the turret plate. When tightened down this eliminates the play in the plate. Of course the bolt must be loose to rotate the plate.
Larry

dbern
12-19-2020, 08:27 PM
Largom, Larry; I see what you mean by play on the turret. I press on it and it does move up and down a-bit [enough to cause the variance I'm looking at]. When looking at the frame I don't see where to place a washer. Is their anyway you could take a picture and post? Just can't wrap my head around where it would go.

turtlezx
12-19-2020, 09:20 PM
LARGOM has the idea lotta play in the turret shim it to tighten it up
also oal varies if there not a shell in all stations turret will rock

largom
12-19-2020, 09:31 PM
Do not know how to post pictures. My Lee press has the 4 hole plate. Press has 3 rods which connect top of press to bottom. Bolts are in top end of rods and bolt
heads sit lower than plate. I took the right side bolt out of rod and made spacer to put under bolt head level with plate. I then made a washer from a piece of aluminum that sits on top of spacer and also on top of plate. Bolt goes back and when tightened eliminates play in plate.
I do not use this press for handloading but have a decapping die in one station and a Lee hardness tester in another. Can't post picture here but could send one
to your cell phone.
Hopes this helps, Larry

Taterhead
12-19-2020, 10:09 PM
Mixed brass will cause varying degrees of deflection. Thinner brass will create less resistance to seating, therefore will have shorter COLs. Also, depending upon the shape of the seating plug and how it interfaces with the bullet profile, will also affect COL.

Add the deflection and slop in the press, and the tolerances will stack.

dbern
12-19-2020, 11:46 PM
largom, Larry; I think I understand. Your stabilizing the plate at the top or downstroke of the press. So when the turret is up the washer provides stabilization so it does not rock. I will have to give it a try and see if I can't do the same.

Everyone; thanks for all the suggestions, I appreciate the help. I really want to solve this issue or at least have a better tolerance.

DougGuy
12-20-2020, 12:01 AM
For the record, if you are loading 9mm to max pressures, .010" - .012" variation in COA can send pressures alarmingly high if your load data is for the longer COA and you get rounds that are shorter.

The same caution applies when crimping and you don't get enough crimp or there isn't enough case neck tension and boolit setback occurs when the boolit is stripped from the magazine and shoved nose first into the feed ramp by the slide. Either way, when you are at your max on the load data, you basically have zero room for error.

country gent
12-20-2020, 12:01 AM
Some variation is from fit of bullet in the seater stem. It may not center as well as it needs to or a bullet thats not started as straight may not get t the same point. The lee dies usually do a pretty good job. Another issue may be if your crimping and seating together in one step varying case lengths may affect where the bullet actually stops.

Rizzo
12-20-2020, 01:18 PM
I also have seen the seating depth vary.
At the time I was tumble lubing with Lee Liquid Alox.
Over time the seating stem would get a build up of the LLA from the bullet and change the seating depth.
Those that tumble lube should keep that in mind.
Hope that helped.

onelight
12-20-2020, 03:05 PM
I have also seen bullets push back up a bit after seating I guess it might be air compressed under the bullet pushing it up . But I confess when they vary 5 or 6 thousandths I don't worry about to much on handgun rounds if they function safely . I don't see a difference on paper the way I shoot.

jetinteriorguy
12-20-2020, 04:07 PM
The Lee press is designed to have that play in it. It will deflect the same amount every stroke as long as you’re not short stroking it and has a minimal affect on seating depth. With the Lee design there is no way to eliminate this and it’s not necessary. Instead of measuring COAL try measuring to a datum point equal to bore diameter. I’d guess between short stroking, differences in bullet ogives, how the differences in ogives affect fit to the seating stem, and using the COAL as a point of reference all these things would account for the differences. Using a datum point would most likely yield a much more consistent measurement. I’ve been through all of this, my method for determining seating depth is to first find what depth using a datum point will just pass a plunk test in my tightest barrel, then set my seating stem .010 deeper to account for bullet variances and start my load work up using loading data that most closely resembles the bullet type I’m using. I do this with a dummy round, not a live round. I also load up half a dozen in the final seating depth and hand cycle them to check that they feed properly.

onelight
12-20-2020, 08:15 PM
The Lee press is designed to have that play in it. It will deflect the same amount every stroke as long as you’re not short stroking it and has a minimal affect on seating depth. With the Lee design there is no way to eliminate this and it’s not necessary. Instead of measuring COAL try measuring to a datum point equal to bore diameter. I’d guess between short stroking, differences in bullet ogives, how the differences in ogives affect fit to the seating stem, and using the COAL as a point of reference all these things would account for the differences. Using a datum point would most likely yield a much more consistent measurement. I’ve been through all of this, my method for determining seating depth is to first find what depth using a datum point will just pass a plunk test in my tightest barrel, then set my seating stem .010 deeper to account for bullet variances and start my load work up using loading data that most closely resembles the bullet type I’m using. I do this with a dummy round, not a live round. I also load up half a dozen in the final seating depth and hand cycle them to check that they feed properly.

This is how I do it to /\

Ford SD
12-20-2020, 09:00 PM
I have found that using a progressive press with 5 stations

Having one station seat the bullet .. then the next station crimp and check/ verify oal reducees the plus and minus

I also had one shell plate 5 station where it was machined where if you measure the shell plate where the shell sits it varied about .005

onelight
12-20-2020, 10:49 PM
One of the things I like about the Lee carbide factory crimp die is when you have it properly adjusted it touches the shell plate at the same time as the sizing die so you have 2 points contacting the the shell plate I don't think this is a big deal but it does help eliminate some of the rocking in the shell plate on a progressive.

PbHurler
12-21-2020, 12:38 PM
Measure the overall lengths of a few of each type of bullet (base to tip) I'll bet you'll find that much variance in the bullets themselves.

I've had this same "issue" with Berry's, Xtreme's and Rainier's (all plated varieties) I've gotten variances in Hornady 230 gr .45 RN's too, but I can visually see slight differenced in the ogive curvatures.

I'd suggest you "cull" a few of the longer bullets, and use those to initially set up your seating die. (of course check them for chambering & feeding as well) and run the others with this depth "locked-in"

I get some pretty wild variations on commercial bullets, it'll surprise you how inconsistent they can really be.

Another thing, this could be simpilfied if the seating stem is flat & not concave, & seating the bullet by the ogive. A flat seating stem would get you closer to a uniform OAL, it's just those few thousandths of inconsistency will be hidden inside the case, rather than outside.

onelight
12-21-2020, 02:17 PM
Measure the overall lengths of a few of each type of bullet (base to tip) I'll bet you'll find that much variance in the bullets themselves.

I've had this same "issue" with Berry's, Xtreme's and Rainier's (all plated varieties) I've gotten variances in Hornady 230 gr .45 RN's too, but I can visually see slight differenced in the ogive curvatures.

I'd suggest you "cull" a few of the longer bullets, and use those to initially set up your seating die. (of course check them for chambering & feeding as well) and run the others with this depth "locked-in"

I get some pretty wild variations on commercial bullets, it'll surprise you how inconsistent they can really be.

Another thing, this could be simpilfied if the seating stem is flat & not concave, & seating the bullet by the ogive. A flat seating stem would get you closer to a uniform OAL, it's just those few thousandths of inconsistency will be hidden inside the case, rather than outside.
Good post /\