Should I be concerned about the variances here?

B

Burcaw

Inactive
Tonight I loaded up the following...

9mm
Mixed Brass
CCI No. 500 Primers
5.4Gr of Unique
115Gr Everglades Ammunition Plated Round Nose Bullets
OAL between 1.093 and 1.123 (Difference of 0.03 over 100 rounds)

I cannot for the life of me figure out how to get a consistent OAL out of my press and dies. I'm using Lee Precision for both. Any help there would be greatly appreciated.

I put this load data together after reviewing numerous loads posted on this forum and others. From what I kept seeing, this was middle of the road, but please correct me if I'm way off base.

So I think my two questions are...

Does this load data look acceptable?

And

Is the variance in OAL something I should be alarmed about in this particular load?
 
Does this load data look acceptable?
Click to expand...

Yes. You're on the low end. Speer #14 starts at 5.6gns.

Is the variance in OAL something I should be alarmed about in this particular load?
Click to expand...

I'd shoot them without hesitation. Unique behaves "spongy" (tolerant, absorbs, if you will, loading anomalies) under light bullets - especially taper crimped light bullets. You'll be fine. If for instance, you had a 124gn bullet and under it was Bullseye loaded to the top end, I'd be far more concerned. But Unique has enough slowness (especially with this light charge), and the bullet is light enough, to where extreme pressure is highly unlikely. But. . .

I'm still concerned as to why your OAL's vary so much. 30 thousandths is a lot. I don't have an answer. I could only speculate that your load equipment is sloppy with a lot of "play" in the ram assembly. Or the die settings weren't tight. I can only guess.

I do recommend resolving the issue before moving to a load combination that would be less forgiving (heavier bullets, and/or faster propellants).
 
The simple fact is that bullets are not manufactured to the same tolerance as ball bearings. The ogives are slightly different so yes you wind up with a range of OAL and not the same specific measurement.
 
Are you using a round nose profile for round nose bullets on the seating stem in your seating die?

Look up in there to see if the profile in the die matches the profile of the bullet.

I have to agree with the other guys, .030" is a lot, and would also look to see if the seating stem is moving on you while loading. I have to crank my .357 dies tight with wrenches or they will slip.
 
I'll take a serious look at the press and dies tonight. There is a possibility that the dies aren't seated tightly enough. The breech lock, although convenient, does have a little play in it as well.

I've also measured numerous cases and bullets that are being used, and while that may account for some variance, it's still a wider variance than I usually read about.

Thanks to everyone for their input so far. This forum has always been very helpful.
 
Last edited:
Paint a dozen bullet noses with a Magic Marker so you get a mark where the seating die touches them. Seat the bullets. Then use your caliper to measure from the case head to that contact point to see if that is consistent or inconsistent. If the contact location is consistent and the COL is still not consistent, then the problem is with the bullet maker's inability to produce a consistent nose profile. This is not uncommon because the bullets of more than one set of tooling are often mixed in the box.

Also, look at the slight bulge on the case where the bottom of the seated bullet is located. Is this even all around the case? If some are not, then the bullets are slightly tilted, which affects where the seating die stem touches down on them. Using a Lyman Multi-expander type powder-through die will creates a little step that lets you set the bullet in squarely and will eliminate 90% of that tilt.

Case%20Flare%20Style%20showing%20tilt_zpspxacapfz.gif


If the case head to seating die mark is also inconsistent, then something is happening after seating. One possibility is the crimp die may be moving the bullet from overdoing the crimp. To check for this, pull and measure some cartridges after seating but before crimping to see if the COL is varying on bullets just out of the seating die or only after crimping. If it is only after crimping that the variability is apparent, back the crimp die off a fraction of a turn. It should just take the flare out.

If the cartridges come directly out of the seating die uneven, the bullets may have enough lube on them that the air compressed in the case is pushing them back up a little. In that instance, try adjusting the seating die body down while backing the seating ram stem out until the crimp shoulder in the seating die starts the crimping process. It can be very light and you can allow the crimp die to finish the crimp. The idea is to get just enough to counter the compressed air.

If your bullets do not have a lube on them and if your cases are clean, the friction should be adequate to prevent compressed air from moving the bullet. In that case I would put the bullets in mineral spirits or denatured alcohol to remove any oil. If you don't tumble your cases to a polish, try that as the smooth, clean surface inside the case mouth will produce more friction with the bullet than a dirty one does.
 
OAL consistency really doesn't matter if you think about it. I've lived through this frustration when I first started loading and came to understand that as long as I was within OAL tolerances, it didn't matter if I hit a precise number or not. As long as your round fits the chamber and fires without issue, you're good to go.

That being said, I do care about OAL under one condition, when I load defensive rounds. When I do that, I work with a single case manufacturer. Pick one, doesn't matter which. This is the only time that I strive for consistency.

I am guessing that you are using cases from multiple manufacturers. You will find a lack of consistency in their length, which will translate to your OAL issue. With lead cast bullets you will find inconsistency in length, also affecting your OAL. I've never tested my plated bullets for length, guess you should look at that as well.

Good luck. Be safe.
 
"...if I'm way off base..." Have you created your own data through supposition instead of using proper data from a manual? 5.4 grains of Unique is safe, but buy a manual.
If the OAL is 30 thou different, in all likelihood your seating die is loose, like Burcaw says. Possibly how you're operating the ram, but more likely to be a loose die.
 
For this one, I referenced the Lee data that came with the die set. I also collected about 6-7 different loads from forum users (from The Firing Line as well as others) and created what I believed to be a middle of the road load.

Last weekend I had loaded 20 of these with a OAL of about 1.115. I shot them in a Walther PPX, and a Star 9mm. They functioned, recoil felt close to factory, no stuck cases, no primers popping out, nothing out of the ordinary.

It was last night when I loaded the batch of 100 where the variances became more pronounced. My test loads were all the same brass, and the 100 batch was with mixed brass, so that may explain some of the variance.

I think the biggest issue is how I have my press and die set up. I'm focusing on that tonight and I'll see if it makes any difference.
 
I've been reloading for about 40 years. When I started I didn't know anyone that reloaded so I learned everything from reading... a lot. Posts like this both scare me and make me shake my head in wonder because its obvious the OP doesn't have a manual. BUY A MANUAL!!! BUY TWO OR THREE!!! That should be the FIRST purchase.

Sheesh!
 
Currently reading The ABCs of Reloading. I get load data from manufacturer's websites and make further decisions/adjustments based on quite a great deal of reading, albeit on the Internet, but still reading. In addition, I find dynamic/interactive environments like forums to be a great resource.

But I'm not above the old paper standby, and I'd be happy to take any suggestions for reading. What were the books and manuals that helped you the most when you began loading?
 
The ABCs is good but nothing replaces a real reloading manual or two. If you settle on a brand of bullet you like, a manual by that manufacturer will give good data for OAL and tested loads. Don't bother with Lee's manual as they do none of their own testing but get their info from other's data. I like Lyman, especially if you get into cast bullets. Sierra is my goto because I mostly use their bullets for rifle loads and I like the way Speer's book is laid out. There are certainly many other good ones.

It's not just about the data. All the manuals will have other info such as accuracy techniques, ballistic tables, etc. A manual is a must.

I'm not jumping on you in particular, it's just that I see this type of post a lot and reloading is a discipline that is an ever-learning journey.

Be safe, the eyes you save may be mine.
 
Great info, thanks! I didn't know that Lee doesn't do their own testing. Maybe I'll take a walk down to the library tonight.

Thank you as always!
 
Update.

So I got home, checked my seating stem, it was nearly perfect for the RN bullet I'm using. I then adjusted my die, and loaded 10 rounds. My shortest was 1.118, and my longest was 1.127.

I had some play in the die, and I found an obstruction that may or may not have come in contact with the press. Cant say if that altered the distance the ram traveled, but who knows.

So I went from a varience of 0.03 to a varience of 0.009.

All chamber pefectly as well. Mixed brass, same charge as before.

I think I had my die very poorly adjusted earlier, I will take much better care from now on.

Thanks to everyone for their input, I appreciate it. Now I'm off to the library. Always more to learn.
 
You must log in or register to reply here.
Back
Top