Bullet seating depth - doing this right?

J

jmg-in-alaska

Inactive
I am brand new to reloading and am loading my first batch of rounds, 200 grain Nosler Partitions in 30-06. I am using a Lee Classic Turret Press kit, although I added a few additional tools, to include headspace gauges, bullet comparator gauge, digital calipers, and a digital scale that compliment my Lee safety powder scale. I have gone through a number of processes for measuring cases, bullet seating depth, etc. and just want to run numbers by everyone here out loud before I actually load everything down with powder in the cases. I have used various data from both the Lee manual that came with my loading kit and I have the Nosler loading manual as well. I trust the Nosler manual a little more just because the Lee manual is not bullet specific.

First up, cases. Both Lee and Nosler manuals have the distance from the head to the first point on the shoulder at 1.948", and to the other end of the shoulder at 2.109". This tells me that my headspace gauge, which I am using the Hornady gauges on a digital caliper, should run somewhere between these numbers, 1.948" – 2.109". I also have a Lyman headspace gauge, that does not really measure anything, you just put the case into it and verify it is at least within SAAMI specs.

What I did is I went to the range and I shot off about 40 rounds, in three different bullets. I shot Barnes X, Winchester Super X, and some super-cheap-on-sale PPU rounds. I measured every case with the Hornady headspace gauge to see what the headspace is for a fired round in my rifle. The Barnes and Super X all measured at 2.0385", and the PPU mostly measure right around 2.039", with one of them coming in at 2.040. Based on this data, I decided I would adjust my resizing die to 2.0385" so that I know I didn’t go too far out on the headspace. Once the dies were adjusted, I resized 25 cases that I got from friend to this spec. I then cut all of the cases to length with the Lee case length gauge specific to 30-06, and then chamfered/deburred the case mouths, and then double checked each case in the Lyman gauge as well.

Next up, figuring out seating depth for this specific bullet. I’ve done a couple of different methods here to figure out my distance to the lands. First, I took a fired cased, slightly dented the mouth and then set a bullet into it. Then, I slowly and gently put the round into the chamber, and closed the bolt slowly. I then carefully withdrew the round and measured it with the Hornady bullet comparator. This tool effectively measures to the ogive rather than cartridge overall length. The measurement I got with this method came to 2.778". I believe this means that 2.778" is my distance to the lands at the ogive for this particular bullet under this particular test.

I then did another test. I inserted the bolt and closed it down in the chamber without dry firing it (firing pin is back). I then took an old piece of fishing rod blank (was going to go get a dowel rod but I had this around already instead) and ran it up the muzzle to the bolt. I placed a clip on the rod right at the muzzle so that it was flush with the muzzle.

Then, I removed the bolt from the rifle and inserted a bullet without a case into the chamber. It dropped to the lands, and I held it there with a long screwdriver against the lands. I then took the fishing rod blank and ran it up the muzzle again until it hit the tip of the bullet. I then placed another clip right at the muzzle. I now had two clips on the rod which to measure at. The problem was I would be measuring from the outside of one clip (the bullet clip) to the inside of the other clip (bolt clip). So I took a third clip and set it right up flush against the bullet clip, so now I had two clips to measure the inside distance on. That distance came to 3.276” – this, I believe, would be my COAL if I placed the bullet right up on the lands.

One I had this COAL for this specific bullet, I then seated it into a dummy case at this exact distance. Then I measured it with my Hornady bullet comparator as I had done earlier, to the ogive. I got 2.665” under this test. This is different than I got on the test above where I simply pushed a bullet that was snug in a case into the chamber, as that was 2.778”. But, this is essentially off by only .013”. I feel like this amount of difference could come in having pushed the bullet further into the lands in one test over another, my replacing clips in the second test, etc.. It seems to me that the test where I pushed a cased round into the chamber could have pushed the bullets into the lands by this much, as opposed to the bullet “just touching” the lands on the second test. I don’t feel like .013 here is a significant amount. My plan was to seat this bullet .020 - .030 off the lands anyway. If this .013” is a significant amount, please let me know, and please let me know how to get a more accurate reading?

So this is where I am at. My plan is to seat the bullet so that on my bullet comparator it comes in at 2.750" at the ogive. This would put it off the lands .028" under the one test I did, and .015" off the lands under the second test. This should give me a COAL of 3.261”. Should I go any further than that? Maybe another .005" so that I am at least .020” off the lands in the second test? This would only be .033” off the lands from the first test. By the way, I did measure my magazine length, which is 3.372", so no matter which way I go above, my rounds will fit and feed from the magazine just fine.

In comparison, a factory 220 grain Remington Core Lok on my bench measures at 2.746" to the ogive, and has a COAL of 3.250". Obviously a different bullet, and set to SAAMI specs by the factory, but I feel like I am close to on par with where I need to be.

The only thing that even makes me hesitate on these numbers at this point, besides the .013" difference in my two measurements to the lands, is that my Lee book says that my minimum COAL on a 200 grain jacketed bullet should be 3.295” when using RL 19 powder (which I am). My COAL is going to be significantly less than that - .034" under. I am not sure this is a significant problem because I think the Lee book covers all bullets, and my understanding is that this distance can change dramatically by bullet because of design, ogive distance, etc.

So, at this point, my plan is this:

1.Resize cases to 2.0385” on the Hornady headspace gauge, and then double check all cases with the Lyman gauge to verify they’re within tolerances. Then cut mouth with case length gauge.
2.Load three cases with 52 grains of RL 19, and then 3 more cases each at .5 grain intervals up to a max load of 56 grains, per the Nosler book data.
3.Seat the 200 grain bullets at 2.750” to the ogive on my bullet comparator, which should give me a COAL of 3.261”.
4.Go out and do round robbin shooting on all of these, checking for pressure signs, to find the most accurate load. Then maybe play with the seating depth after that?


Does anyone see any issues with anything I’ve done here, something I’ve missed, something I should have done differently? Should I seat bullets in step 3 at 2.745” instead of 2.750”?

I know this was a long post, but this is my very first batch of loads that I’m putting together and I really don’t want to mess up my rifle, or, well, blow myself up. This entire post is essentially just about everything I have learned about this hobby over the course of the last 3-4 weeks. I've read my loading manuals, many websites, including here, to learn all I can about this hobby so I can be as safe as possible. If you’ve made it all the way to the end here, you are awesome, and thank you so much for any assistance or advice you can provide.
 
You are trying to reload to to much precision. What you are doing will fit your rifle BUT what happens when you are out in the field and you buddy needs a few rounds so you toss him a few and then they do not chamber in his rifle?

You are a new reloader KISS. Yes you are using your own brass but your chamber will be different which is why I always full size. Yes it does shorten case life but it aint like you are shooting some rare caliber. I full size everything so if I am hunting with some one and they need some rounds hey NBD it is a carma thing you just might need them to drag your deer out.

Yes It does cause the cases to wear out a bit faster but I would bet that you can probably find once fired 30-06 brass as cheep as me which is $5.00 per 50. I am still reloading cases that my Uncle loaded with head stamps prior to WWII. I am down to 80 of those pre WWII head stamps.

For OAl it has to fit in you mag well so I just use SAMI specs.

I do not use a 200 grain bullet I use 160 grain Nozzlers, Sierras, Herters but mostly my own hard cast and gaschecked. 2700 fps and no leading.

I would also suggest you purchase a broken case extractor and keep it with you in the field as it sure can save you a bunch of heartache.
 
What you're doing will work fine, but there are some steps that you could skip. I assume this is a bolt action rifle? What I do (and this is just me...not saying this is the only way of doing things). Pick a piece of brass and use it as a "dummy load". Next take your bullet of choice, seat it with your die but do so obviously long. Now, chamber you dummy round (hopefully the bolt wont close due to the bullet seated too shallow). Use your bolt to try to chamber the round and press the bullet into the case as it's nose is engaging the rifle lands. A little force is best, and if it wont go pull the case out and use your die to seat it a few thousandths and try again. Eventually you'll get it sized so the case chambers with the bullet right off the lands. Now use this dummy case to set your seating die, and mark the length, bullet, etc with a sharpy on the case itself. Now you can start loading different powder charges and see whch one shoots the best, watching for pressure signs, etc. Even if you have to adjust your seating die you can use the dummy round to return to what that bullet seats at when just touching the rifling lands. As an aside, since you're new...I trim my .30/06 cases to 2.484 after each firing and neck size a few times between full length depending on how they chamber in my gun. My brass never sees another gun, so I dont worry about loaning to others. Nobody should be taking another's reloads for use in their gun. If you can, try picking up some H4350 and some 180 grain bullets...and work up to 55 grains if you can safely get there without obvious pressure signs. I shoot a lot of 180 grain Nosler partitions and Sierra Game Kings with that load...it's accurate in both my 06 rifles, and it's taken many deer over the years. Good luck and be safe!
 
If you are shooting Nosler bullets, buy their reloading book and load your rounds to their suggested COAL. Then do your load work up, and after you find that good load, then tinker with the COAL.

I've been reloading for decades and have the good loads for a number of rifles. It wasn't till just recently that I noticed that many of my favorite and most accurate loads (and powders used) are the same as what Nosler suggests. That can't be a coincidence, so buy the book and save some time.
 
Sounds like a lot of work for an easy job. Fire your brass. Back die way off so all you get is neck tension. keep firing case till bolt starts to close hard on empty fired case. Now start setting your die down .002 at a time till bolt closes firm but easy. You now have your case length set. Seat a unprimed case with said bullet,set the length long. Flame bullet or use a marker, chamber round, look at bullet for marks, keep setting till no marks are seen. From there you can start your testing to find out what your gun prefers. Some like a jump, some don't. Same with brand of bullet, some like a jump( Serria) some dont( Bergers).
 
I'm new to rifle reloading also, but I've studied the subject sounds like as much as you, and here's my thoughts:

Precision is why some of us reload. Ignore remarks that you're overdoing it. Some things may only give a CH of more precision and the trouble may not be worth it, but it sure is better to go a little overboard on making sure things are a good as you can rather than be sloppy.

Here's the best idea I've found (thanks Zero333) for finding your lands. It is for bolt action rifles. I've searched hi and low and this makes the best sense to me. It involves removing your firing pin (you need to know how to do this if you don't already) and removing the ejector (very simple - it is in these videos).

http://www.wheeleraccuracy.com/#!information/p62ad
 
K2man- Why would you want to go through all that work?. Let the gun tell you what length it likes. That is the best way. With new brass it will most times take 4 to 5 firings before the bolt will get sticky ( depending on your load). At that point in time you now have a case that is to long for your chamber. With the die set up and slowly being turned down on the case you can achive a .002 set back
( That is the best setting for 90% of all guns). Finding the Lands, while is importat,in the end really has nothing to do with what your seating depth is going to be. The bullet in most cases will dictate that. And in case your wondering-Yes I do shoot comp. out to 1400 yards. I have been down the road the OP is traveling and am just trying to save him some steps that will gain him nothing but time.
 
4Runnerman's approach to finding and setting the brass shoulder is the method I use. As for bullet seating, for years I loaded the bullet slightly off the lands for load work up. But, not all bullets or rifles shoot best with the bullet seated like that. Now I go with a factory COAL for load work up and then adjust COAL. Both methods work fine, and which is best is a guess.
 
Thanks 4runnerman, I appreciate your experience and sharing your knowledge. So you are saying that we can fire new brass, then neck size it the next 4 or 5 times we reload? And at that point, we should just bump the shoulder back .002" or so?

You also raised a few more questions. You stated: "Finding the Lands, while is important, in the end really has nothing to do with what your seating depth is going to be. The bullet in most cases will dictate that". Can you explain this further?

How do you determine your seating depth if you don't determine it by how far off the lands the bullet is?

What distance off the lands do you end up with in your loads?
 
k2man- Yes to your first question. Now 4 or 5 firings is a starting point. It depends on your load, if a stout load might only need 3. The point is-You want to let your brass expand to YOUR chamber. When the bolt get sticky you are there.
Simple place fired brass in press, with the die way up, slowly lower your seating depth in very small increments. Run die down, take case to rifle and chamber, if still sticky, lower die a smidgen more, continue this till brass chambers with, here is the part you need to play with, the bolt will close with very little resistance, Now set die down .002 more. That number might change once you fire that round. If after firing it, the bolt opens with resistance, set you die down .002 more. Now keep in mind as one other stated-This round will be for your rifle only. The point here is-You want the least amount of brass stretching possable to extend brass life.

As for seating depth- You do need to determine the depth, but only for a starting point for each different bullet you shoot. Once that is determined it is used as a starting point only. Seat your bullet ( depending on bullet) Bergers like to be jamed and Serria's like a jump. If your playing for acuracy, while all steps are important, this one is (To me) the most important. Load in groups of 5 changing seating depth .005 at a time, from (Berger in lands to Serria .005) off lands. Each bullet will shoot best at a distance off lands that you will need to find. One cant say that this bullet likes to be .005 off the lands and think the next brand bullet will be the same. each will be different.

My seating depth for my 6BR is .008 off the lands. That is with a 107 Serria Match bullet. My Bergers-Which I don't really shoot anymore were jammed .002 into lands.
Keep in mind now-I trim brass after every firing and Anneal every 4th load.
 
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Thank you 4runnerman! A very clear, step by step explanation that totally makes sense to me. Gotta print that out and paste in in my reloading manual.
 
Glad I could help k2man- But there are many people on this forum that make me look like an idiot. Uncle Nick is one of them. I heed most everything he says.
I also ( if memory works) Think he has posted a pattern that you can print, cut out and apply to your die that will tell you how much to turn to seat your bullets.
maybe he will read this and re post it. There are lots of things you can do to increase your accuracy, but that is all up to you and how far you want t push it, Me-I am never satisfied. Makes the game never end, which is fun for me.
 
I load one round as long as possible and still fit in the magazine. I then chamber the round. If it chambers without jamming the bullet into the lands I'm good to go. If it is a little too long I bump it back until it fits. Once I get the depth figured out I load the rest.
 
jmr40 brings up a great point that I missed. All my rifles have sled beds in them. I have removed the magazine box. They are all single load rifles as all I do is Target shoot.
jmr40- How many times have you run into the Mag box being long enough that your bullet will hit lands?. Now I run all Savages and they are know for deep throats, so I have never had that happen.All my loads are to long for the box.
 
There are really two approaches to reloading, and you need to decide what your goal is:

Do you want to wring the last bit of accuracy out of your rifle?
Do you want to make ammunition that has acceptable accuracy for your application.

If the former, keep doing what you are doing.

I fall firmly in the latter camp. I started out chasing the last tenth, but after I figured out how many rounds I fired and range trips I made trying to make already good groups smaller, I stopped.

For some people, reloading is as much or more of the hobby than actual shooting, and there is nothing better than tinkering with different powders, and charge weights, and seating depths to try and eek out the best possible performance from your load and rifle. I am not that person.

For seating depth, I make a OAL gauge by taking a sized case, and with a hacksaw cut a slit in the neck, from the mouth down to the shoulder. The neck should hold a bullet firmly enough that it will not move on it's own, but loose enough that it can slide in with a little pressure. Put in a bullet so that it is really long, barely held by the case, and chamber it in your rifle. When the bullet reaches the lands, it will push the bullet into the case. Gently remove it and measure with your calipers. This is your max OAL for that bullet in your rifle.

Do that several times, make sure you are getting a consistent measurement.

Take the same gauge, with the same bullet, and use it to set your bullet seating die. What I do is set it so there is about .020" jump to the lands, assuming I can get that long and still fit in the magazine. If I can't, I use the max that will fit the magazine and still feed reliably.

I then tune the load to the rifle with the powder charge. I have never had a problem finding a load that has acceptable accuracy for the application.

Yes, I admit I am leaving some potential accuracy improvements on the table. For me, it is not worth the extra effort and time, plus wear on the barrel to find that last couple tenths.
 
That's a pretty complicated way of measuring distance to the lands. No need to do that or to mess with custom gages, magic markers, or cases with slit necks.


Seat a bullet long in a sized case. Stuff it into the chamber with your thumb. Keep seating the bullet a smidge deeper until the round drops out from gravity alone when you point the muzzle up; at that point it just clear of the lands.

This is a pretty idiot proof way of getting a perfectly good answer that is highly repeatable (unlike all the other ways of doing it).
 
30Cal- That would work pretty good. As I stated- It is only a starting point anyhow. I will have to give your idea a try. My concern on this method would be that the brass is only set back .002 so it might be the brass sticking also to a point giving you a false reading. I think if you have more then .002 setback the brass would fall right out. I think if you have your brass sized to your rifle with only .002 shoulder bump and you put a case ( with out bulet) in your chamber it is going to stick already.

I will take one of my sized brass and see how that works.
 
I would suggest one tool if you are going to shoot the 30-06 much.

Get a Gerrard Tri Way trimmer, its about $108 shipped (takes a couple of weeks sometimes)

It indexes off the shoulder (resized), its accurate, its easy (drill needed) and it chambers and deburs in the same operation.

I trim every round but you could do every 3.

If you want better checks the Hornady compactor gauges works well. It has a fixture that has two types of adaptors (package with both maybe). One is for measuring shoulder (something like 6 adaptors that fit most cartridge out there). the other is for the OGIVE of a bullet for COAL.

the lands one is easy, run it in, push set the hold screw, push out the bullet and measure the length with a micrometer (you need a good one , metal that measures to .001 , it does different bullets it simplifies it. I have two, both were for work but now at home, dial type and digital. Digital I used for the shoulder setback and the COAL and lave the device on it

The Hornady should is the easiest way to ensure brass longevity. Check the length before re-size (it also does it on the shoulder) and note it, then start setting your re-size die. Start loose form (i.e don't'; have the press cartridge adaptor touch the die) You work it down until you get about .003 shorter. As long as shot in same gun works fine.

While you can get into the super detail those items get you going and then you can decide how much attention to detail you want.

Using that setup I got a .250 group at 110 yds recently, a couple of groups under 1/2 inch and out of 12 targets 11 were sub MOA. I was also testing a variety of loads and lengths. Normally I am about a 1 1/4 shooter. So I had a gun that can do it, loads that were pretty good if not optimized and the shooting mechanics. Shooting mechanic on next session may not be there and all goes wild. It takes all 3 and the loads done decently are the least factor (assuming you find a node that the load is consistent in

As noted once you have some baseline established you can move up to more precision.

Until you are stable though, you won't know if its you, the load or the gun .

I have shot some great groups only to fail to do so again.

There is a lot to the mechanics of shooting that are far more important than the precision of the rounds themselves.

Once you have that down then you can see what rounds are doing.

Mechanics mean trigger pull consistent (straight back and squeeze and here a good trigger helps a lot) as well as consistent sight picture (scope or irons) as well as consistent pressure into your shoulder as difference in recoil makes a significant difference in where a bullet leaves the barrel and hits the target.
 
k2man - How far are you trying to shoot?

The reason I ask is recently my father wanted me to start reloading for his 30-06 he just got. I know he would love to hit steel at 300m but secretly I think he hoping for 500.

I have learned quite a bit here, good thread.
 
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