I'm running through a work up on 10mm in my LNL AP and am having alot of trouble getting my RCBS taper crimp seater to seat to a consistent length. I'm using Hornady 180gr XTP's and the COL is specified at 1.260". I'm targetting for 1.263" to leave myself some room. This die seems to have the worst tolerance of the others I'm using to load other calibers. Im getting mostly 1.263 but some are coming in anywhere from 1.267 to 1.257 anything under 1.2595" I'm pulling. The seater seems to match the shape of the bullet pretty good and they seem to be going in straight, just not consistent. Am I missing something?
Seating tolerance???
- Thread starter BunnMan
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rcmodel
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Do you have cases in all the die stations when checking seating depth?
If you only use the seating die station, the shell plate may be flexing and giving you variation.
rc
If you only use the seating die station, the shell plate may be flexing and giving you variation.
rc
Not all the time but the only stations that would influence the shell plate are #1 (sizer) and #2 (bell) and #5 (seat). The sizer touches the plate so I don't figure that would matter with a case or not...right? The bell might change things I guess but it doesn't feel like alot of load when I work the press.
thump_rrr
Member
I'm assuming that you are using a seating die which is seating on the ogive.
If you are measuring to the tip of the bullet you will always see a variation since the bullets are not 100% identical.
If you measure using a bullet comparator which measures on the ogive you will see that you are probably within a couple of thousandths of an inch of each other.
If you are measuring to the tip of the bullet you will always see a variation since the bullets are not 100% identical.
If you measure using a bullet comparator which measures on the ogive you will see that you are probably within a couple of thousandths of an inch of each other.
243winxb
Member
From what i read online............
Try a different Bushing. Hornady also makes shims to fit these. Takes the slop out.
There is a shim for between the ram and subplate, to keep it from flexing. INFO from ar15.com I dont own Hornady
Try a different Bushing. Hornady also makes shims to fit these. Takes the slop out.
There is a shim for between the ram and subplate, to keep it from flexing. INFO from ar15.com I dont own Hornadythump_rrr
Member
Unless you are at your absolute maximum load with the rest of them already showing pressure signs you should be good to go.
HPs can open up the OAL if your seater plug doesn't fit right. A generic one-size-fits-all seater plug can slightly squish the HP cavity. This squished bullet will mic out longer, because the narrower end fits deeper into the rounded seater plug.
You can get custom seater plugs made for a specific bullet or you can make your own.
You can get custom seater plugs made for a specific bullet or you can make your own.
243winxb
Member
It would matter if each station of the plate was a different thickness.
Keep the shell plate full, it does matter. Why seat at 1.263 to leave some room when the length specified is 1.260 then pull loads that are 1.2595 and under? This makes no since, pressure problems can be had from to much or to little room in case. Quite frankly you are getting a great tolerance on seating depth and if you want it blunt you are being way to critical. Hell you are getting a low reading of -.006 thousands or really -.from the listed COAL. Your high + reading is .004 over your length and +.007 over the published length. Well if you can get much better on a single stage press with bullet variation let me know, on a progressive this is great. I think if you measured your bullet length you would find this much variation just in the bullets. If you measured the Comparator length of the bullet, Distance from base to Ogive, you will probably find that the length difference is really in the bullet point and the bullets are actually seating to the same depth when seated by the ogive. If you are really that worried why don't you measure all you bullets and sort by length then load by bullet length.
My Nolser .400 hollowpoints have a thin leading edge. I used to slightly flatten the edge when seating, no crimp. But the worst offenders have been FP and HP plated bullets. Seating those long FPHB Berry's, I could see the tip deform different amounts, depending on the headstamp. With thicker brass, you could easily see a line partway down the tip from where the nose started to form fit to the rounded plug. Custom seating plugs for those bullet types have taken care of my OAL problems. With custom plugs, I get less than 5 mics of extreme spread, now, and no deformed tips.
I wouldn't worry about pressure problems unless you're trying to push the envelope. I'm more worried about proper feeding in a pistol. I usually find an OAL that works and make sure my OAL range is equal or less. When I mark my reloads as 1.20, that means that batch of ammo is somewhere between 1.19 and 1.20. If a 1.2" load fits in the chamber and loads from the mag, then they all should. I guess other people might look at the same loads and call them 1.19 minimum.
*You may think that pistol seaters index on the ogive. But the Lee pistol seater plugs I've examined all make contact at or very close to the tip of the bullet, only. The tip of the bullet enters the plug only a very small amount, and the ogive is nowhere close to the seater, at all. When I made a custom plug for my Nolser HPs, I enlarged the seater cavity so the bullet would go in it as far as possible, and it's still not reaching the ogive. The seater plug of most centerfire pistol bullets is significantly smaller in diameter than the bullet. There's no way it could index on the ogive anywhere close to where a chamber throat would make first contact.
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showmebob
Member
I hold to +/- .005 for my handgun loads. Recently while loading .40's I found some were way long. Turns out the cases (all the same brand) were of slightly different headstamp and the crimp function of the RCBS die was pinching the bullet and not letting the bullet push into the proper seating depth. I could not measure any difference in the cases but there was a definate difference in them I could not find. I backed off the crimp a little even though it looked fine and everything has worked perfectly since then. Yes, I do set OAL with all stations of the LNL AP full.
Good luck!
Good luck!
Who me? I am calm and no you didn't cover that.
Hollow points are not known to have tight length tolerances.
Try measuring the OAL of a handful right from the box.
After you take the first measurement on each bullet, rotate it 90 degrees and measure again.
Write down all the numbers.
If you want to further check, pull some loaded bullets and measure a few.
The force to seat the bullet can also deform the tip slightly if it touches the seater plug (the flat plug is NOT correct even for large bore hollow points).
Try measuring the OAL of a handful right from the box.
After you take the first measurement on each bullet, rotate it 90 degrees and measure again.
Write down all the numbers.
If you want to further check, pull some loaded bullets and measure a few.
The force to seat the bullet can also deform the tip slightly if it touches the seater plug (the flat plug is NOT correct even for large bore hollow points).
Ok, I hear ya on the shell plate being full, though I don't understand it fully and it didn't seem to have much effect when I measured cartridges seated either way. Given the idea of loading the shell plate alm the time. Do you always stop four cartridges short to avoid seatin with an empty station? Not mocking...these are honest questions.
As far as why my target is 1.263, that's because I know I have a consistency problem...or at least I perceive one. I understand that the given COL in the manual os a minimum and I should not go under due to pressure problems. The loads I built this run are a work up. So the first few steps I didn't worry so much if I was under. 001 but towards the NE, I wasnt about to compromise. I haven't run across the theory that being over minimum causes pressure problems as well until you mention it Muddy. I've never seen a max COL listed in my manuals. If my thinking is off base...correct me, that's why I'm asking. How do you properly figure your target COL? It seems obvious its not safe to go under minimum at high charges. If going over causes the same problem than this is an impossible pursuit because theres no way to nail it spot on given the deviation I'm getting. I understand different bullet lengths, that mkes sense..but comparing off the ogive doesn't seem to compliment a minimum COL. Am I too concerned about the standards listed in the manual?
As far as why my target is 1.263, that's because I know I have a consistency problem...or at least I perceive one. I understand that the given COL in the manual os a minimum and I should not go under due to pressure problems. The loads I built this run are a work up. So the first few steps I didn't worry so much if I was under. 001 but towards the NE, I wasnt about to compromise. I haven't run across the theory that being over minimum causes pressure problems as well until you mention it Muddy. I've never seen a max COL listed in my manuals. If my thinking is off base...correct me, that's why I'm asking. How do you properly figure your target COL? It seems obvious its not safe to go under minimum at high charges. If going over causes the same problem than this is an impossible pursuit because theres no way to nail it spot on given the deviation I'm getting. I understand different bullet lengths, that mkes sense..but comparing off the ogive doesn't seem to compliment a minimum COL. Am I too concerned about the standards listed in the manual?
Blue68f100
Member
COAL is what works in your gun. Every gun is different. As a rule you try to load as long as possible that will feed reliably in your gun. Since 99.99% of pistol bullets are not target grade, All very some. Loading on a Progressive whether the stations are full or not should land you in a ±0.005" (0.010" spread). With all stations full, same mfg brass with the same number of firings will land you in the 0.003" spread. The variation will not impact accuracy. Measure a box of factory and you will see more spread than 0.010".
Reloads manual give you guide lines not absolute. So there will be variations.
Reloads manual give you guide lines not absolute. So there will be variations.
There is a clearance present that allows the shell plate to rotate.
If all the positions are filled the loading on the plate will be more uniform than if only one is filled.
The plate will 'rock' differently resulting in slightly different positions at the top of the stroke.
Or you can torque the plate down to remove all clearance and it cannot rotate.
If all the positions are filled the loading on the plate will be more uniform than if only one is filled.
The plate will 'rock' differently resulting in slightly different positions at the top of the stroke.
Or you can torque the plate down to remove all clearance and it cannot rotate.
Blue68f100
Member
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