So, as the title says, what kind of tolerances do you accept when you seat your bullets? Ive never really seen much on what most loaders feel is acceptable and not too unpractical. What is good enough when you have a properly worked up load? I think you would probably have to be pretty accurate if you're loading real close to the lands, but otherwise, with a jump is pretty much what I'm asking about.
Seating Depth Tolerances
- Thread starter axarob44
- Start date
I just loaded a 20 Hornady Match BTHP and they ranged from .002-.003 in OAL differences. I tried my damn best to get them as close to 2.800 as possible but some where 2.800 and others were 2.797(ish) despite the bullets all being consistent in length.
Kills my OCD but i am shrugging it off.
Kills my OCD but i am shrugging it off.
Most dies (a good one with the right seating cup) will seat off of the ogive, not the meplat/tip, so "bullet length" is not a valid measurement.
You need a bullet comparator to tell if the ogives are consistent. Varies lot to lot, but generally Hornady does a decent job. Berger probably being the most consistent of anyone (not counting solids, etc). I wouldn't accept anything over .002 - .003 personally. That's just a sign of shitty QA overall.
You need a bullet comparator to tell if the ogives are consistent. Varies lot to lot, but generally Hornady does a decent job. Berger probably being the most consistent of anyone (not counting solids, etc). I wouldn't accept anything over .002 - .003 personally. That's just a sign of shitty QA overall.
Typically if you're off the lands still, .010 at the least but .015-.020 you'll start seeing a difference..
I have one and I still have some variances that is driving me nuts. I locked down my RCBS seater after I got the OAL I needed on first two bullets.
That's not that great. Like BLKWLFK9 said it probably won't make a difference unless you are chasing the lands, but I figured the Hornady BTHP's were better than that. A (much older) lot that I have are.
Calipers in good order? Test them on a fixed object.
Calipers in good order? Test them on a fixed object.
I dont have a fixed object that I would consider prime to check measurement but I am zeroing it every time on the comparator. Killing me having these differences on the Ogive when I have the seating stem locked down. The Nossler RDF seated much more consistent last week.
Just run it down on a piece of brass multiple times and see if you get the same reading every time.
If you have ogive variances then it isn't the die.
If you have ogive variances then it isn't the die.
I’d say anything within .004-5 is fine. Pay close attention to how hard you are pressing down on the handle and get in a rhythm. How hard you press can def make a difference.
****Was refering to your first post Precision Underground****
Can you explain on this more? I don't really see how you would have any say in the matter. Don't you just seat until it stops at the end of the stroke. I'm using a Redding Competition seating die, are you using a different type of die?
Can you explain on this more? I don't really see how you would have any say in the matter. Don't you just seat until it stops at the end of the stroke. I'm using a Redding Competition seating die, are you using a different type of die?
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Thousandths are very very tiny. Take your calipers and try to open theM to .001. It’s so small you can hardly see it. Pressing harder on the handle squeezes everything tighter and can make a .005-009 difference. I like to find a medium pressure where all “slack” is gone from the press but I am not putting body weight into it. You can press it however you want, just do it consistently.
Just pulled out my RCBS mechanic calipers and my OAL is much closer than the digital calipers were reading. Quite disappointed now but I did get them for $20 from Amazon.
Yep that's what I thought. No bullet ogive variance would be as wonky as you had posted.
Get you a good pair of Starrett or Mitutoyo calipers and you'll be set. Buy once, cry once!
I don't press at all at the end of the stoke. I just lightly come to a stop at the end of the handle travel, no pressure on the handle. My press doesn't cam over either (Lee cast classic press}. I'm going to do some experimentation next time.
