Can .30-06 Brass be too Short? (Bullets Seating Loosely)

[Justin]

I've recently started reloading .30-06 ammunition, and I've run into an odd problem.

I'm using a Lyman turret press, and a set of RCBS dies.

I have found that some of my cases (some which are even once fired Lake City!) won't let me seat a bullet properly. The bullet is so loose in the case that I can pull it out with my fingers.

Measuring the cases shows me that the lengths on them is between 2.478"-2.492". The cases that are closer to 2.494 seem to seat just fine.

The bullets I'm using are 180 gr. Sierra Game Kings.

So, what's my problem? Are these cases bad? Screwing the seating die into the press further doesn't seem to solve the problem, and I'm at a loss as to what to do about it.

 

[Ol` Joe]

Case lgt means nothing inre to bullet tension, the necks ID is the key. Normally the ideal is to have the inside of the neck measure ~0.003" less then bullet diameter. What diameter is the expander ball? It may be over sized. The Brass may be work hardened and not sizeing down properly. Are you full sizeing or trying to neck size with a FL sizer?

 

[Sunray]

Like Ol` Joe says, the length has nothing to do with holding the bullet in place. Nor does the bullet weight. However, trying to use different length cases is going to give you seating grief.
2.478" is under the trim-to length of 2.484". 2.494" is the max case length. I'd pitch any that are under the 2.484" and trim all of 'em to that length, chamfer and deburr. Then set the seating die up again. And look at the expander button.
You'll want to separate the LC brass out too. Milsurp brass needs to be loaded differently than commercial brass.
Any once fired brass must be FL resized before using it in another rifle.

 

[Justin]

Thanks guys.

I screwed the sizing die down and did a full-length resize (or as close to it as I could without breaking anything.) After doing that, the bullets seemed to seat just fine.

Sunray-

I wish I'd have read your post about trim-to length before I loaded these rounds. For the ones that are under that length, is there a safety issue? Also, will different lengths of brass result in fluctuations in accuracy?

 

[Sunray]

"...as close to it as I could without breaking anything..." Close doesn't count. Take out the decapping pin and resize properly. Brass that isn't correctly resized will give you feeding issues.
"...about trim-to length..." Read your manual carefully.

 

[Ol` Joe]

I screwed the sizing die down and did a full-length resize (or as close to it as I could without breaking anything.) After doing that, the bullets seemed to seat just fine.

Proper set-up of most FL sizeing dies is to screw the die in with the ram at TDC until contact, lower the ram and add a sixteenth or slightly more turn then lock it in place. This takes the flex out of the press and allows the die to fully size the brass. Take a look at the shellhold/die contact with a case in it and ram at the top of its travel. If you can see "air" the die is too high.

The little extra trimmed off your brass won`t hurn. I`ve purposely trimmed to -0.015" under max instead of 0.010" a lot of times just to keep from needing to trim as often. As long as the brass is of even lenght and under max, that is the most important.

 

[ants]

If it's 2.478" now, chances are it will be 2.484+" after two firings

Justin, have you read that rifle brass stretches each time it is fired&resized? When you shoot it, the case expands to match chamber diameter. When you resize it and reduce its diameter, it squeezes brass up toward the neck and lengthens the neck each time. In a couple fire/resize cycles your brass will be trim-to length. Trim-to length is not minimum length, it's just the dimension you set as a trimming length.

Read the instructions that came with your equipment, but often you set a full-length sizing die by raising the ram all the way up, then screwing the die down until it contacts the shellholder. Then you lower the ram and screw the die another 1/4 turn down. Nothing will get broken. This will size the case correctly and (if your expander stem is correctly sized) open up the inside diameter of the neck to hold your bullets.

After the case is fired in your chamber, you can neck-size only and shoot it in that same chamber without full-length resizing, but I suspect that you're still a beginner. Just do the full-length sizing procedure until you get in the rhythm of reloading and gain more experience.

Finally, maybe you have bullets that are undersized. Measure them (don't just read the label on the box!) to make sure they are 0.308" along the straight portion of the profile (the straight portion is called the bearing surface). Most of my Game Kings measure 0.3075 to 0.3080". Anything in that range is good, just make sure your caliper or micrometer is zeroed properly before you measure.

 

[Zeede]

Umm, sounds like you need a reloading manual. Or two. I'd suggest Lyman's 49th Edition that just came out.

Cameron

 

[NuJudge]

Do you have a Vernier Caliper or micrometer?

If you have a Vernier Caliper, measure the inside of the case neck, and measure the loose bullets. Also measure the expander ball on the decap stem on your sizing die. You can also do the last two with a micrometer.

The bullets you are using should be about .308". The inside of the case neck should be about .001" or .002" smaller than that.