Need help with consistent seating depth using seating die

[misterc01]

If you look inside the neck and if you see a "ring," THAT is a donut. If there is ring around the case at the bsse of the case neck, that is also a donut. You inside ream or neck turn to remove them. as needed. Glen Zidekers's book
"Handloading for Competition Making the Target Bigger" has a great explanation.

 

[skipglo]

All,

I am not sure what is going on but when seating 120 grain Nosler Ballistic tips in my 7mm08 using my Forster competition seating die, I am not getting consistent seating depths to ogive when measuring with a Hornady comparator. My guess is the seating stem in the die is pushing on the bullet in a different spot than the Hornady gauge but the odd thing is it only happens on every few bullets. So for example out of 5 seated bullets I will get these ogive measurements:
2.235, 2.238, 2.233, and then a random 2.220 and a 2.224. Target depth is 2.235. These are not the actual measurements im getting just an example of what I have seen. Should I simply seat them all a bit long and then slowly bump them to depth?

I am finding it more and more after 40 years of reloading in all calibers. These new razor sharp pointed bullets are not consistent as they want us to believe. I find match grade in most calibers differ not only in weight but length consistently screwing with seating depths. I believe that is the whole reason Hornady made a specific seating plug for their Atips. There is one thing you can try that has helped....seat the bullet part way...say 1/3...turn the case seat 1/3 turn the case finish. Just me

 

[066wally]

All,

I am not sure what is going on but when seating 120 grain Nosler Ballistic tips in my 7mm08 using my Forster competition seating die, I am not getting consistent seating depths to ogive when measuring with a Hornady comparator. My guess is the seating stem in the die is pushing on the bullet in a different spot than the Hornady gauge but the odd thing is it only happens on every few bullets. So for example out of 5 seated bullets I will get these ogive measurements:
2.235, 2.238, 2.233, and then a random 2.220 and a 2.224. Target depth is 2.235. These are not the actual measurements im getting just an example of what I have seen. Should I simply seat them all a bit long and then slowly bump them to depth?

Just curious if the small difference in seating depths affect your groups? I don't measure all of my loads for consistency and probably have differential depths. Maybe I could squeeze some more accuracy, but I doubt it's worth my time.

 

[19 Badger]

Curious on how much neck tension you have..... Inconsistant or very light neck tension can cause erratic seating depths...

 

[RYEWSKY25284]

All,

I am not sure what is going on but when seating 120 grain Nosler Ballistic tips in my 7mm08 using my Forster competition seating die, I am not getting consistent seating depths to ogive when measuring with a Hornady comparator. My guess is the seating stem in the die is pushing on the bullet in a different spot than the Hornady gauge but the odd thing is it only happens on every few bullets. So for example out of 5 seated bullets I will get these ogive measurements:
2.235, 2.238, 2.233, and then a random 2.220 and a 2.224. Target depth is 2.235. These are not the actual measurements im getting just an example of what I have seen. Should I simply seat them all a bit long and then slowly bump them to depth?

One thing I might recommend checking is.......Primer seating depth.
If they aren't uniformly seated that could be giving you a false reading @ ogive.
Also periodically cleaning out the seating plug keeps things from sticking and pulling at the bullets

 

[Roo78]

Was having a similar issue but I'm not using competition seater. Started seating twenty tho longer then going back thru and setting final depth. Helped with my issue with my gear.

 

[GLTaylor]

Could you share with us how you recognize donuts (I've read about them and still don't understand) and how you remove them? Or post directions?

Epoletna,
Donuts are a ring of excess brass that forms at the base of the neck at the shoulder junction. They most commonly occur after sizing brass down when modifying brass - say from 30 cal down to 264. The excess brass has to go somewhere. A ring (donut) forms at the neck base and constricts the base of the neck such that a bullet can't be fully seated past the neck base - or if seated, done so with Way more pressure.
There are two cures. One is turning your case necks and running the cutter down to just touch the shoulder. Size your brass normally, then tun an expander mandrel into the neck to push excess brass to the outside before turning.
The other method is to size the brass and run a cutter down the inside of the neck to remove the donut from the inside. Use a caliber specific cutter for this. Personally, I prefer the outside neck turning method. Only has to be done once either way. Regards.

 

[IHFarmer07]

Could you share with us how you recognize donuts (I've read about them and still don't understand) and how you remove them? Or post directions?

What sedancowboy said or what I and several others use is gage pins to find them, like what machinists use.....some others also uses the bullet too after you fired the rnd but I've not had luck using that method. You can buy gage pins on Amazon for reasonable or a hole set.

I and others use the K and M neck turning tools, they have a carbide mandrel that has cutters to take them out from the inside. For me, the carbide cutter mandrel didn't work as good as I thought it would.

Now, I don't know if that alone will help/work but, after buying the tools and not knowing much about some of this, I used the neck tuner as it was bought with their "standard" cutter for awhile to no change to things. So I moved to another process which was neck reaming. I bought a forester trimmer and a id reamer or two and that really didn't work. I did more research on the subject and found some other ppl on another site talking about "chucking" reamers and they come in all kinds of sizes. I bought several and returned those to Amazon that wasn't going to work. I tried them for awhile and it really sucked to hold the brass and it just wasn't fun.

Then, I researched more and stumbled on shooters saying that basically to turn necks properly to get rid of donuts you have to have the same or close to the the same degree cutter as your brass neck/shoulder. So I got the proper cutter degree for my brass, which K and M now sells carbide cutters in different degree angles. In my research I found out that a person should just barely touch the neck shoulder, "don't ask how many pcs of brass I ruined".

So, in a long winded answer short, IMO the ONLY way to take donuts out is neck turning......get a neck turner that has the correct degree cutter for you neck/shoulder, turn just to the neck/should junction and that should do it.....don't go to deep, you will blow the necks off or the neck will come off in your sizing die......don't ask how many has done this for me!

Now, what I do is I have everything set up to where I have neck turners and trimmers just for one cartridge, if I reloaded for 10 guns I'd have 10 trimmers and neck turners, although if it's a 300-400yrd and under gun, neck turning is not worth it IMO......

Sorry for the long winded answer/process but I've just about tried it all.
Good luck!

 

[IHFarmer07]

Curious on how much neck tension you have..... Inconsistant or very light neck tension can cause erratic seating depths...

Problem is is if he's got donuts it's very hard to have consistent neck tension.

 

[Muddyboots]

Ok, I know this is not what most would consider doing but it is one way that I have addressed inconsistent cup core bullet ogive measurements. So get popcorn ready: I seat bullet approximately 0.020 less than targeted CBTO, measure the round CBTO and then set the seater micrometer for the difference. Before I press again, I rotate the round 180 degrees to help bullet alignment. When I seat bullet then, the CBTO is spot on. I hate doing this but my experience with hunting cup core is the ES of the bullet ogive measurement can be up to 0.005 or more. Could I sort? Yes but for the distances I shoot this gives me decent MOA and I am not freaking out over the ogive differences. What is even more aggravating is the next box of same bullet will have different ogive as well. This is with premium cup core hunting bullets. DANG it adds time!! Another good reason to load Hammers! Set the micrometer and just load!

 

[DFHarley19]

All above are great! The only one I haven't seen is.... I was having problems just like yours until I bought Mitutoyo digital caliper! China's digital caliper is inconsistent.

 

[IHFarmer07]

All above are great! The only one I haven't seen is.... I was having problems just like yours until I bought Mitutoyo digital caliper! China's digital caliper is inconsistent.

Lol you learned the hard way too huh!? I just bought a couple really good shape used "genuine" Mitutoyo calipers myself.....no comparison......someone recommended me getting the 8" calipers and I didn't listen on the first cheap caliper but I sure did on the mitutoyo's! I need one more 8", but I bought two ip67's, on 8", one 6" and the 6" is going to the shop to work on the farm equipment.

 

[DFHarley19]

Your right! I learned the hard way! But I need doing that so I will know why!

 

[epoletna]

GLTaylor:'
'Thanks for that explanation. I'm going to cut one of my old cases in half to see if I can see anything there.