Bullet seating

[Velvett]

Im using the Lee 9mm die set (christmas gift). the constancy of the bullet depth is always off by in the 1000th's for example ill set it to give a 1.161 OAL, and then ill start loading, some will be 1.161 OAL, others will be 1.164 OAL, or maybe a little shorter 1.158 OAL for example. i know it could be the bullets (berry's 124gr .356) . if there longer than the 1.161 OAL im looking for ill usually go back and re run them, and it will be better if not right where i want it. Is this something i should be looking to overcome, or is this normal? At the moment i'm just loading for target work. But eventually id like to load for competition so if its not normal. id like to nip it in the bud sooner than later.

Edited February 21, 2012 by Velvett

[Skydiver]

Are you loading on a single stage press or a progressive press?

If it's a single stage press, I would expect a more consistent seating.

If it's a progressive press, the seated depth you should rely on is the bullet that seated when all the slots of the shell plate are filled with cases in their appropriate stage of loading. This will be the state that almost all of your bullets will be loaded in. (The exceptions will be the first few bullets, and last few in a batch, or when you encounter a jam and have to kick out a shell.)

Unless you are pushing the edge of precision, 0.005" usually doesn't make that big a difference in precision and accuracy for the distances we shoot with pistols.

[mcracco]

+/- .003" for OAL? That's fine for a 9mm pistol load. If you were into benchrest rifle at 100yds it would be a problem.

Skydiver raises a good point about seating on a progressive.

[mpeltier]

I never in 30 years of reloading have ever checked this. So out of curiosity I went and checked 20 rds of each of the 11 different loads I have on hand. 9 are factory and 2 are my reloads. Both my reloads were +/- .002 and the factory ranged from the best of +/- .001 (silvertips) to the worst of +/- . 004 (ww WB) and an overall average of +/- .003, so I would say your results are just fine.

[sroe3]

Two things I've notice that reduce variation: sorting brass. Variations in the brass thickness tend to make the press run harder/easier. Lube. Using case lube trimmed my COL variation down to 1 or 2 thousandths.

[Velvett]

Thx, guy's. yeah, i'm loading on a Dillon 550b, this helps allot. I also (just today) measured some factory rounds, and found the same inconstancy that Mpeltier did. Of course id like mine to be better than factory. ill also try to lightly lube them. i haven't been due to the carbide die's. And it is mixed brass, Thanks for the warm fuzzy.

When you reload for pistol competition do you generally try to use new same brand brass, and high quality bullets, or do most people use mixed brass and affordable bullets?. I can understand those measures taken for long distance rifle.

[polizei1]

I have a Lee Classic Turret press and mine various like that as well. Sometimes even a bit more, but it's never been a concern, they all have worked for me! When I first started I kept trying to adjust the die but it's an issue with the press itself. I'm not sure about the Dillon 550, but I would venture to guess it's not a big deal.

Edit* I load mine to 1.140" and get between 1.138-1.143.

Edited February 21, 2012 by polizei1

[sroe3]

I use mixed used brass and moly coated lead. Some guns allow it, others not so much. A competition barrel would likely be tighter.

Edited February 23, 2012 by sroe3

[Velvett]

@sroe3 and others thx, I had a reloading session last night, i lubed the cases and it DID make a BIG difference. Numbers went down to +/- 0.002 with the odd one in here and there, and those weren't off enough to ruff my feather's. It was much better results. "i'm giddy as a schoolboy" . thx everyone.

Edited February 24, 2012 by Velvett

[j0n]

I never lube nor sort cases, and experience the same variation. It results in a bit higher standard deviation (40fps or so) but I'm not loading anything super hot, nor am I right at the ragged edge of power factor, so it's inconsequential.

[Schuster]

I load with a Lee Pro 1000 and started loading 40 and never had a problem except for the first/last couple on length. It was a real eye opener when I switched over to 9mm. I was having difficulty getting a consistent length until I was told that it was normal with 9mm to be off a little bit. Since then I have moved my base from 1.135 up to 1.140 and now I might have some anywhere between 1.136-1.143. I have chronoed several difference rounds to see how consistent I was and my largest standard deviation was only 12. Now I am not pushing the limit by any means so I am definitely on the safe side, but if you are getting close to max then I would look at something more precise.

[Sarge]

Velvett it sounds like you are fine and getting some good info. Lubing cases is the way to go as it just makes things easier and as you found out more consistent. Sorting brass does make a big difference as well. Don't worry about getting new brass just keep collecting it as you come across it. I am in the 40k piece range of 9mm brass right now. I pick it up after matches and sometimes guys just give me bags full. Shooting Production loads you can load 9mm brass many many times.

[truborshooter]

So random thoughts on the subject

What make you think $.10 - $.20 bullets are all that perfect?

Since almost all seating dies work off the curvature of the bullet,

get a spare seating stem and make a epoxy face that matches your

exact bullet and maybe you will see a difference.

OAL doesn't mean much other than magazinability.

Only the outside diameter touches anything.

Your calipher is only rated +/- .001, that means .025 could

read .024 or .026 and still be within the accuracy of your tool.

Add a little operator hand problem and ....

Get a multileaf feeler gauge, remove the axle screw, mix them up on a table,

pick 2 - 5 at random and measure. Them turn them over, read the labels, and add them up.

Let us all know how well you did.

Edited February 26, 2012 by truborshooter

[Mike_P]

Running on a progressive using mixed headstamp, I originally was chasing after consistant OAL's. But after running thousands upon thousands of rounds realized... In 9mm this is sort of normal since each brand of brass is a little different, and not something to worry about. Considering the accuracy of digital calipers, I'm happy as long as it's +/- .004 either way. I typically load to 1.135" so I have plenty of room to go in either direction without worrying about pressure or length.

The accuracy of my rounds has been more accurate than I am, so unless I see some major issue I'll continue to produce my ammo with those minor variations.

[sroe3]

Well said, Mike.

[Ofishl1]

Thx, guy's. yeah, i'm loading on a Dillon 550b, this helps allot. I also (just today) measured some factory rounds, and found the same inconstancy that Mpeltier did. Of course id like mine to be better than factory. ill also try to lightly lube them. i haven't been due to the carbide die's. And it is mixed brass, Thanks for the warm fuzzy.

When you reload for pistol competition do you generally try to use new same brand brass, and high quality bullets, or do most people use mixed brass and affordable bullets?. I can understand those measures taken for long distance rifle.

I shoot weekly in USPSA and have shot some majors, usually in the majors I run a mixed bag of brass since they keep them all and I found if I inspect them prior to loading I can cull out the ones with warts.

I have never had a brass problem in a match to date, if I am going to Chrono, I make sure the brass has been fired a few times, (new brass will run slower) and will sometime run only Starlines to eliminate mixed brass speed variances that could affect readings, especially if I am cutting close to major. I run Berrys mainly for practice and Zero, or Montana Golds for matches. I want consistent feeding in my Liimited and Open gun, so performance here is critical. I have found too much variance in some of the other brands that created major feeding issues, so stay with the best when accuracy and scoring is the focus. So my answer is mostly mixed mixed brass, STARLINE, SPEER, WIN , RP, PMC, BLAZER all run (I just say NO to Amerc or win NT or steel) and high grade bullets for match performance.

O1

[Sin-ster]

What you're reporting, especially with mixed cases and those projectiles, is actually pretty consistent in the grand scheme of things-- well within the normal variance ranges.

One thing that hasn't been mentioned yet that I found to have a pretty significant influence on COAL is the amount of bell you're using. In my experience, "too much bell" was the culprit of the most inconsistencies in ultimate COAL (once mixed brass and variance in projectiles was eliminated as a possibility).

I also discovered that the number of cycles you've put your brass through will also begin to skew the extreme ranges of your COAL, although we're talking a matter of .001 at most. Most importantly, as others have said several times already-- provided you've allowed enough cushion in your COAL to not contact the rifling or give you nose dives in the magazine, the variable range you're reporting is not going to make a difference in the grand scheme of accuracy or velocity.

It sounds like you're meticulous like me, though!

[Velvett]

Yeah, i like my ducks in a row. I hadn't concidered the bell, all-tho i think its minimal (by eyeball) ill revisit it. just to make sure. thanks for the tip. this has been a very productive thread.

[Rotisiv]

Have a dillion square deal B to load 9 major seat to 1.15 use 7.2 grains of auto comp have a power factor of 170 clean burning doesn't dirty the gun.

[RH45]

Different OAL used to drive me crazy when I loaded varmint loads for .223. Even though OALs were different, the measurements to the ogive of the bullets were consistent, so, I don't get too excited about OAL anymore.

For local matches, especially in snow, sand, or mud, I'll sometimes run mixed brass, because I know I'm not going to get it back.

For matches I care about, most of the time I'll use once-fired brass of all the same headstamp, which I've found to be the most consistent at a chrono, and most accurate.