Same Setup, different ogive measurement. Need Help

[jeo556]

Just finished loading some .243 Win and I'm having a problem that I cannot seem to figure out. I am using a Redding comp seating die to seat 105 lapua scenars and the measurement to the ogive isn't consistent. I'm looking to seat them to 2.288" and 34 outta 50 were right on the money. However, the other 16 are measuring anywhere from 8 to 4 thousands shorter. This is the second time that I've reloaded with these specifics and the first time everything was fine.

Here is where I'm really confused. So I pulled some of the bullets from the shorter rounds figuring that maybe there was something with the ogive measurment. Nope, all the bullets measure 0.704" from base to ogive and are consistent with the rest of the box as well as one bullet pulled from a correct length round. What gives?

Is there something wrong with the bullet seating stem? I've heard that Redding makes a stem for VLD bullets but don't know if that will help.

Also of importance, I didn't trim the brass as the sample that I measured were all spot on, is this my problem?
Any and all advice appreciated. Thanks

<span style="font-weight: bold">Other info</span>
Lapua Brass
Lapua 105 Scenar
Redding comp seating die
RCBS rock chucker
Using Hornady lock n load bullet comparator with calipers for measurement

 

[aron]

Re: Same Setup, different ogive measurement. Need Help

Are you compressing the load or varying the charge?

I've noticed when doing load tests that the compressed loads require turning down the redding type s seater die.The greater the charge, the more I need to turn down the die.

 

[TRAAV]

Re: Same Setup, different ogive measurement. Need Help

Are these compressed loads?
How many firings on the brass since anealing?
What kind of neck tension are you running?

 

[jeo556]

Re: Same Setup, different ogive measurement. Need Help

No and No. I'm using 40 grains of H4350 and there is plenty of room in the case. The brass is virgin and I believe .003 neck tension IIRC. I just used the standard method of determing the correct bushing and went with that.

 

[mtang45]

Re: Same Setup, different ogive measurement. Need Help

Any chance primers may be slightly protruding on some of your cases and flush on others?

 

[TRAAV]

Re: Same Setup, different ogive measurement. Need Help

Is the bullet maybe sticking in the seating stem.

 

[LARMIKE]

Re: Same Setup, different ogive measurement. Need Help

Maybe the bullets are just a bit off. Measure the bullets first, Base to ogive. Then load from the largest lot you have.
I get 12-14 different boxes from a box of 500 SMK and less than 6 from Nosler. That is why I make my own bullets. Hope this helps.

 

[jeo556]

Re: Same Setup, different ogive measurement. Need Help

I have measured the bullets alone from base to ogive and all of them are 0.702". I'm starting to think that it has something to do with the seating stem. I'm going to email Redding techincal staff and see if they can shed some light on the problem. Till then, I'm still all ears. Thanks for the responses guys.

 

[doc76251]

Re: Same Setup, different ogive measurement. Need Help

With .008 - .004" and only 16 I would say the operator has changed how he operated the ram when seating. If nothing else changed, the bullets are the same, the brass is the same the only other variable is the operator.

FWIW I find that loading the rounds .010" long and then do a final seating via the knob to be beneficial. I also load to a compressed charge so on occasion I get "push back". This technique alleviates that issue also.

Cheers,

Doc

 

[jeo556]

Re: Same Setup, different ogive measurement. Need Help

I also thought that I may have done something wrong. So I pulled some of the shorter rounds and re-seated them. Came back 0.004 short again. I try to make sure that I'm consistent with my press operation, maybe I'm not.

 

[JimGnitecki]

Re: Same Setup, different ogive measurement. Need Help

It is possible for the threaded micrometer to come entirely "out" internally, if you accidentally adjusted it out too far. This would give you the symptoms you are experiencing, as the threaded rod moves around or gets jammed at the correct height but not threaded (I have done it

).

I have also seen this ahppen when a tiny piece of debris gets into the seater, and itnermittently affects the seated height as a result.

I would:

- Disassemble and clean the entire die
- Re-assemble, being careful to thread the micrometr in a fair bit - not bottoming it, but say 2/3 in
- Re-install in the press to rough correct height using an already seated cartridge
- Fine tune with the micrometer

Jim G

 

[milo 2.0]

Re: Same Setup, different ogive measurement. Need Help

Pull your die apart, see if a bullet sticks in your seating stem.
If it does you can do two things, buy the vld seater, or remove some material from the stem.
While it is apart, clean the stem, and where it rides in the die. Before assembling it put a light coat of oil on it.

I've seen this before too, when I'm seating a bullet, I never seat it all the way on the first stroke. Get it close, then rotate the case 1/4 turn and seat, then rotate 1/4 turn again and repeat. I think it helps with concentricity also.

 

[former naval person]

Re: Same Setup, different ogive measurement. Need Help

I agree with the suggestions so far...one other I received and tried out really helped...seat the bullet as you normally do, then leave the ram up with pressure on the bullet while you get the next round ready to seat...give 20 seconds or so on the ram. Seems to let the tensions settle out. JMHO

 

[jeo556]

Re: Same Setup, different ogive measurement. Need Help

Update, I disassembled the comp seating die and took a good look at the seating stem. I cannot say that this is the standard or VLD stem but looking into the cavity in the bottom there is no way that the tip of the bullet is contacting the stem, so I doubt that this could be the culprit.

I also cleaned out the interior of the die and there were no obvious signs of debris. I still gave it a once over and applied a small amount of lube before reassembling it.

So I'll try to give the 16 that ended up short another go and see what happens.

As a side note I emailed Redding's techinal staff at the onset of this problem and have yet to recieve a response.

Again, Thanks for all the advice you guys offered.

 

[X-fan]

Re: Same Setup, different ogive measurement. Need Help

You have not mentioned how you are measuring the overall length?
Base of brass to tip of bullet with calipers??
If so, that would be your problem.

just as the bullet tip should never touch the seating stem so your calipers cannot do the same? Make sense?

You need something like this.

Hope that helps.

 

[jeo556]

Re: Same Setup, different ogive measurement. Need Help

X-fan, I am using something similiar but thanks for the suggestion.

 

[jcallan]

Re: Same Setup, different ogive measurement. Need Help

I had a similiar experience and found out that my primers were not all the same depth. I now uniform the pockets and it cured it for me. Its hard to look at the primer and see if its .005 difference. I have a Hornady comparator set and what I did to verify that the primers were the problem was use the normal size comparator for the bullet your measuring then stick the comparator used for measuring the shoulder on the other end so that the primer doesnt touch it and it will give you a correct measurement

 

[JimGnitecki]

Re: Same Setup, different ogive measurement. Need Help

Berger King raises a great point.

I recently was given 50 primed once-fired 338 Lapua cases by a friend, who got them from another friend. When I tried to emasure the case length, to see if they needed trimming, I was shocked to find a huge variance in length. I examined the primers, and found that many (most?) were aactually protruding out of the case rim! Some of them up to .010" !

Primers are supposed to be proeprly seated so that they fire consistently and so that slamfires do not occur if using them in a semiauto rifle. They should be at least .033" below the rim surface, and I typically seat them to .006" below the surface.

If the OP's priemrs are indeed soemtimes not seating properly, due to inconsistent or dirty primer pockets, this could be the cause of the variation in apparent (but not really due to the bullet)bullet seating depth.

Jim G

 

[jeo556]

Re: Same Setup, different ogive measurement. Need Help

Another good suggestion guys, I'll take a look at the primers this evening and see if they aren't seated properly.

 

[gvanhyning]

Re: Same Setup, different ogive measurement. Need Help

I would switch to the VLD seating stem. It could be the difference in MEPLAT length if it is contacting your current seating stem. I buy Lapua bullets by the 1K and usually don't have issues with that box but I recheck everything when I start a new box. Same for Berger.

 

[jeo556]

Re: Same Setup, different ogive measurement. Need Help

Any chance that someone could take a picture of a VLD seating stem side by side with a standard one? I've never had a Redding Comp Seating die in the past so I don't know what stem I currently have(I bought the dies used).

Alternately, I'll see if I can get a good pic of the stem that I currently have and see if you guys can identify it for me.

 

[X-fan]

Re: Same Setup, different ogive measurement. Need Help

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Jeo556</div><div class="ubbcode-body">X-fan, I am using something similiar but thanks for the suggestion.
</div></div>
One more scratched off the list.

On a hunch I looked at my Redding 6mmbr die set and the standard seating stem was in the die box. With that seater some bullets do make light bullet point contact...Perhaps yours is different, but I would have another look if you are not positive.
I will pull it out tonight and look, but I suspect the VLD seater grabs the bullet a lot further down.

Interesting comment on the primer protrusion.

 

[jeo556]

Re: Same Setup, different ogive measurement. Need Help

Primers were all seated correctly. I did however get the remainder of the rounds reloaded to the correct length.

Here's the funny part. The last time that I loaded some ammo with this setup(die/bullet/seating depth) I zero'd the micrometer seating stem. When I started this latest reloading session, the first round was long, so I adjusted the micrometer stem for the difference. This gave me the 34 rounds at the length I wanted, the other rounds were shorter. When I went back today I figured that I'd load the bullets long, measure with calipers and adjust accordingly again. Guess what, when I adjusted accordingly the micrometer stem was back at zero, where it should have been the whole time. In hind sight I guess that I should have realized that this was the culprit right away.

I'm assuming that there was something gumming up the interior of the die and not allowing it to work as is designed, and the light cleaning and lube that I applied freed it all up.

Thanks for all the help guys, I appreciate it.