Different OAL with same bullet

Let me see if I can explain this so some of you can help me. I am loading 308 using Sierra 175 HPBT bullets and resized brass of different headstamps. While seating the bullets I noticed there was a different feeling on the bottom of the stroke. The first 3 bullets I seated it was a firm sold contact at the bottom of the stroke but on the next two it was a springy feeling. At first I thought it was perhaps something I had done wrong during the resizing, so I resized them again but to no avail. It did not matter who the manufacturer of the case was. Also the "springy" ones were an average of .010 longer than the other three. Now these cases are on the 4th firing and I will discard after this. Has anyone else encountered this and if so can you shed some light on what it may be.

Pssst Abe each case/bullet will be off a bit. Federals may be 2.014,Hornady 2.0155 etc. Don't fret over it.

Bullets in the same box will have varying overall lengths and Ogive lengths. A compressed powder charge may also cause varying measurements and 'push back' on the bullet during seating.

Like Dave260 said, keep rolling and don't worry about it.

Okay I get that the bullets will have varying Ogive lengths but my OAL jumps from 3.245 to 3.255, that seems way off for it to be attributed to Ogive or case length and then there is the springy feel of the handle on the bottom of the down stroke.

Thanks for the help guys

Bullets in the same box will easily vary in OAL by 0.010" or more. A more accurate way to measure your handloads is the Base to Ogive length, not cartridge OAL. You need a tool to do this. The best I have found is the Hornady Lock-n-load bullet comparator.

This.

The Hornady comparator is what I am using and I am measuring from the base to the Ogive, the bullets that I have measured and used did vary but only .001-.003, not .010, after ding a bit more reading I am starting to wonder if perhaps it has in part something to do with the thickness of the heads on the cartridge.

Head thickness isn't going to matter. OAL is OAL. Your press pushes the case into the die from that base of the cartridge and only uses the rim to extract. The case head could be 2" and it wouldn't affect the OAL.

Check your die, especially if your using RCBS. I 'have never had one of their lock rings work. Tried a piece of lead shot behind the brass set screw and still can't get the ring tight enough to keep from turning before the set screw strips.

Buy the Forster split lock rings for your dies. Much better.

Dave260Rem has it right... 100 bullets out of a freshly opened box aren't going to be exactly identical. I shoot mostly sierra bullets in all my rifles, and several years ago, I noticed that I was getting 'slightly off' ogive and OAL lengths after seating a batch of 50 bullets. After consulting with a few reloading friends, they said that I might have just gotten a bad box of bullets. When I called Sierra about it, one of the techs told me that the bullets they and everyone else makes are going to differ slightly, batch to batch and bullet to bullet. He told me that if I open a new box of whatever bullet I buy, Sierra brand or Hornady or Barnes or Berger, etc and I take the time to measure each bullet, I would get a very small range of measurements that will average whatever the bullets are supposed to be. There are *specs* that Sierra's 175 gr HPBT bullet has to be within before they leave the factory. Will every 175 gr HPBT be EXACTLY the length, weight, and shape it's supposed to be? No. But it will be very, very close. The specs are very tight, and should not matter to all but the most discriminating loader.

I have a long range shooting friend who, upon every new box of bullets he gets, pre-measures them, records the info and groups them accordingly, essentially weeding out the worst of the ones that just came in within specs from the factory. I do not worry with this tedious step, and I still shoot good groups at the range, although I try to get my ogive length when seating the bullets to be within 0.003" of my recorded optimal OAL length.

Next time you get a box of new bullets, dump 15 or 20 on the bench and measure the OAL tip to base, and the ogive length on each one. I think you'll find that slight bullet to bullet variation may account for some of what you are seeing.

Some people are very precise in measuring their bullets. I sometimes check individual bullets if I'm seeing more than normal variance in my handloads. Worst case I've seen was with Nosler LRAB 7MM bullets which had Ogive variances of up to .015.

I know an old shooter who years ago wrote a letter to Sierra and told them their dies, which swage the bullets were worn and they needed to insert new dies into their machines. They wrote him a letter and said thank you for letting them know.

That is awesome! I bet they halted production immediately and saw to the worn dies!

I was blissfully unaware of bullet variation up until the point I mentioned above. I was, and still do shoot decent groups at the range, even when I was just measuring OAL from the tip, rather than the ogive. I'd like to say since paying closer attention to the ogive and similar aspects of more precision loading, that my groups have gotten better. I have no data to support it, but I think it has gotten a little better, but I have never shot a one hole group either. I am sure there are lots of folks out there that can out shoot me and punch one hole in paper regularly, but I just don't have the patience to take those 12 extra steps to try to have exacting (to the Nth degree) ammo.

Edit: I do remember shooting a one shot ragged out hole one time last year, but when I'm doing my best, cloverleaves are usually what I get.

As components improve so does consistency. I'm sure some tool&die maker machinist could explain tolerance between die types but I'm not that smart. I do know neck tension affects groups more than we think.

Have you experimented with changing the neck tension to see the difference in group sizes? I use a bushing neck sizer for a couple of guns and have been curious about this And if I should try different bushings.

Like most things the answer is.....it depends. Never used bushing neck sizer but I've experimented light medium heavy pressure various cannelure placements fast medium slow burners light trimmed cases fully trimmed......and it ain't worth the extra steps. I have found that O'Connor,Layne Simpson,Dr.Ken Howell were right about loading say H4831&.270Win. H380&22-250 H4350&'06,4064&.35 Whelen...RL 22 and that .338 of yours.

My 338 win mag loves H4350 with 225 gr bullets.

When I switched from a FL sixer to a bushing neck sixer with my 308, my groups did improve. I'm only sizing a out 2/3 of the neck.

I try to be careful with sizing to achieve the best concentricity possible. With the bushing die, my 308 loads will typically have .001 or less bullet run out.

I skip all those steps on everything but something I would be shooting in a competition setting. The rest of the time I don't think it is worth the extra steps if the gun will shoot MOA you can kill about anything you can see with it.

As far as bullets seating with a "springy" feel my immediate reaction is compressed load.

Hard to say but could be something with the sizing I don't know if or how that would make sense if you are trimming afterwards. I'm trying to think about that there is a lot of fluff on the internet but I was taught to make the press slightly cam over and I don't think people truly understand what the feel of that is like. I see naysayers on the internet say it torques the press which is improper. No it does not, you don't cam it over anywhere near that hard. I had people that write or did for gun magazines you see on the shelf at the grocery store teach me how to reload. They all did it that way but all presses don't do this.

Could be the dies I had some Hornady Dies at one time I seem to recall loading some .223 they felt springy I disassembled and washed them out with some solvent.

Hard to say on this without sitting there at the bench.

The first step would be to pull the bullet on one that is long and get out the calipers, measure the charge, look at the depth of the charge in the case, measure relative to stated case capacity, etc. You may just be feeling a little crunch and that's ok because powder settles differently one case to the next that doesn't mean you are overcharged, etc. The length is not a concern as long as the bullet measures long, etc.

I'm thinking out loud here.

My die is a Lee and it has been set up according to their instructions, which they say to put a resized case into the press and screw the die in until it touches the shell and tighten the lock ring, this is for no crimp. I am going to disassemble the die this weekend and see if there is anything there that might cause the problem. I read last night where a fella said that he charges the case and then gently taps it to settle the charge, not sure if that would help me or hurt, he swears by it.

Lee makes 2 types of dies one crimps and is more common and the other does not crimp and you run that one down until the shell holder touches the base. Assuming you have the crimp die which is what it sounds like I would say that it does not matter that the case touches the die if you do not intend to crimp. Simply back it off half a turn ( I usually back off a full turn or two depending on case length) and adjust the seating stem down until you get the desired OAL. Run a few through there and see if anything changes.

Tapping the case lightly might not be a bad idea if you think you are compressing the powder slightly because it has not settled in the case. I've run into that on larger stick powder and thought based on the occasional slight crunch I was overcharged.

You'll get it figured out... credit to you for being careful.

I think the dies I once had that felt a little springy had some old oil on them that had dried to something like varnish. Just disassemble and wash them out can't hurt anything.

Thanks Goatkilller

I will have to check but I think it is the Lee standard die as it came in the three die set

if You are using a variety of brass, with each piece of brass having been loaded different numbers of times, you are probably dealing with over worked brass. This gives them almost a memory or rebound while sizing. Annealing or getting new brass and keeping consistent “workable” brass is what I had to do to solve my 3-4K variance. I know this a big of a variance as you have but I would bet it’s part of the issue. Would highly encourage to shoot the same type brass. There are a lot of inconsistencies within 100 pieces of brass from the same company produced at the same time, I can’t imagine a random selection of brass.

Thanks hunterturf

I don’t know yet from experience but I have purchased some competition seating dies hope this will help with inconsistent seating depths looks like just looking at how they work it will have to be dead on with the micrometer reloading is learning process you probably want ever master

No. Micrometer just allows you to make precise adjustments. The seating stem and how well it matches the point of the bullet you are using makes a big difference. For some dies, you have to buy a special seating stem for VLD bullets.