I am reloading for 375 H&H, when seating the bullets, they were not very tight in the case neck.

So I took some measurements:

PPU RN 300 gr bullets, 0.375 dia.
PPU fired brass, resized, not loaded, neck OD 0.394.
Case neck OD after loading, 0.396 - 0.397
Neck thickness measured about 0.011 with slide calipers.

The SAAMI spec for loaded neck dia is 0.402.

Are my numbers normal? Is my die not sizing down enough? I removed the expander, so that's not an issue.

Or are the necks too thin?

Thanks

Any chance your bullets could be slightly undersize ?
Are you definitely seating into cases that have been through the sizer die ?

Forget SAAMI specs and those numbers; they have little practical value in the real world. Especially for reloads. (The tolerances are huge)
Simple; if your bullets are really loose after FL resizing, with no expander ball installed, then your die is too big. For your component suite. Nothing else matters. You already established the dependent variables; now work on the independent one. (And you have established that your bullets are not undersized)
What make of die are you using?
Send it all to me and I will tell you what is happening. Troubleshooting over the internet is just a guessing game.

Try another set of dies.

Try annealing the case necks, It may put a little bit of spring back in the brass.

Hip

If anybody has any resized, but unloaded cases, could you please measure the neck OD?

Thanks for all the responses.

Sized neck is .394 and loaded is .396-7.
Sounds like you have 2-3 thousandths neck tension.
This is usually sufficient for hunting rounds but might be a bit on the scant side for a 375 H&H.

Once your old primers are removed, resize the brass with the expander/decapping assembly taken out of the sizer die and measure the new OD sized neck. if it's .392 or less, load them that way from now on WITH THE EXACT SAME COMPONENT SET.

Ya, it's an extra sizing step but it should insure plenty mucho bullet grip AKA neck tension.

Zeke

.....in other words, your expander ball might be too big.

No expander. Expander removed. 0.394 is as small as the necks ever get during sizing.

quote:

I am reloading for 375 H&H, when seating the bullets, they were not very tight in the case neck.

So, exactly how loose are the seated bullets you describe as "not very tight in the case neck"?
Can you rotate them or move them back ad forth in the necks ?
If not that, are you test chambering rounds and finding that the bullets are forced deeper into the necks ?
What brand of dies are you using ?

Loose enough that when adjusting the seating die with my fingers on top of a loaded cartridge, I can drive the bullets further in with little effort.

Lee dies, brand new.

Have not tried to chamber from the mag, I just single-loaded at the range.

I contacted them today, we will see what they say.

quote:

Loose enough that when adjusting the seating die with my fingers on top of a loaded cartridge, I can drive the bullets further in with little effort.

I agree that situation indicates that an issue exists. With my Redding dies I can press a seated bullet further down into the neck but it takes heavy force to turn the adjustment screw.
In your case I suspect when shooting with a fully loaded magazine the rounds in the magazine will likely end up with deeper seated bullets from recoil forces.
You have measured your bullets at 0.375 dia which I compared to some of my Barnes, Woodleigh and Noslers and my measurments are the same.
I measured Norma case neck thickness ( resisized but not yet loaded ) which went from 0.01181 to 0.01377, apparently about the same as your PPU brass.
The OD neck diameter of the same cases ( resized, not loaded ) went from 0.3937 to 0.3956 inches.
So, mysterious your PPU components result in loosely seated rounds. Do you have other brass and bullet brands you could try for comparison ?
Hopefully Lee can shed some light on the problem.

Or crimp them, forget it and move on. Most likely it is the brass that is too soft; annealing will make it worse. Try another brand of brass. Unlikely the dies; I have never had a Lee die fail to perform.
More guessing of course, as predicted.

quote:

Originally posted by delloro:
No expander. Expander removed. 0.394 is as small as the necks ever get during sizing.

The combination of the brass and dies doesn't play well together for some reason.

It might be a simple case of getting another die that sizes to .392 or tighter. It's very unusual that a standard die doesn't over-size (make smaller OD) than is needed but sounds like that's exactly what's happening.

Zeke

quote:

Originally posted by ZekeShikar:

quote:

Originally posted by delloro:
No expander. Expander removed. 0.394 is as small as the necks ever get during sizing.

The combination of the brass and dies doesn't play well together for some reason.

It might be a simple case of getting another die that sizes to .392 or tighter. It's very unusual that a standard die doesn't over-size (make smaller OD) than is needed but sounds like that's exactly what's happening.

Zeke

I agree. Will see what Lee does. For the time being, I picked up a set of RCBS dies from eBay. They should be here Monday. I will measure what they leave the necks at.

I never had any real problem (except seater) with Lee dies and this brass in .375 H&H:

Federal
Sax (RWS)
Norma

I would rate .375 H&H Lee dies this:

Full Length Sizer - OK
Factory Crimp Die - Excelent
Seater Die - Poor, I had to be careful, it doesn't center bullet properly by it self. It was the reason I switched to Forster. Sizer is smoother a little, Seater is excellent and I use Lee Crimper.

Maybe this info will be useful.

Jiri

Im no fan of Lee dies...With RCBS I take out the expander ball chuck it up and turn off a couple of thousands or what ever until bullets were tight..Ive had to do that on rare ocassions, but you can buy expander balls for rcbs dies in various sizes..

If its not the expander ball fix, then you have a faulty die, simple as that..Send the die back with 3 fired cases from that gun..Im sure they will fix it..

If your fired case measures .392 with no stem I would say its an oversize die...

It's a good practice to neck size "belted cases" to a slightly snug fit in a specific rifle, not on the belt, otherwise you decrease brass life..

Its not a good practice to reload without an expander ball although some do and case life is shortened considerably. Such a practice can increase pressure to varying degrees, sometimes to much...

Lot's of good information above.
Try running the brass into your sizing die and leave it in the die for 5-8 seconds before pulling it out. This may prevent the brass from "springing back" as much as before.

Your measurement of 0.011" wall thickness seems a bit thin to me. The only brass that I have with necks that thin were turned for bench rest shooting. More typical to me is about 0.014-0.016" thick from the factory. With that said, I have not measured the neck thickness of my .375 brass.

Custom neck size die makes a big difference. A set below I made for my 9.3x70. Interchangeable neck size bushings, make a bushing to fit the brass requirements.






Another set for my 400 H&H, along with a bullet size die to take .416 bullets down to .411.

I have some hornady brass the will not size down to hold tension, new un fired. Maybe too soft?

If a die isnt working send the maker 3 fired cases and the die, they will fix the problem, why mess with it and you don't need a crimp on a 375..If the expander ball is too large, stick in in your drill press and use a small file for backing and wet or dry paper 220, and finish with 600..take a thousand at a time, until the bullet is a good snug fit.

I sent the die back to Lee along with a case and a bullet. We'll see what they do.

The RCBS set I picked up from ebay does a better job of sizing the neck.

I had to send back a .375 WINCHESTER dies to RCBS for the same problem----they fixed them/sent a new sizing die.

Hip

I'm a fan of the Lee Factory Crimp Die, they're not expensive, easy to use and work great. I use them as a last step after using my RCBS dies. I use a Lee Turret Press (manually indexing) so it's super easy. Just a thought

The Lee collet dies and factory crimp dies are outstanding designs, as is their decapping pin retention system and newer tapered expander buttons.

I just hope they figure out the issue with my 375 sizer.