I'm stumped....

[bloominonion]

So I reloaded 40 rounds of 25-06 and of them, 10 will chamber. The rest (17) will with some coaxing, and the remaining 13 won't even let the bolt move. I tried to run them through the re-sizing die numerous times to ensure proper sizing since I was necking down 30-06 cases to the 25-06.

I tried blackening them with a lighter (unloaded rounds of course) and the good rounds and bad rounds show the same points of contact. I also have tried measuring (to the best of my ability) and can find no appreciable difference in cartridge dimensions, even in the flange.

Load data:
42gn H4895
COL: 3.100"
Trim length: 2.485"
WLR primers

Addl info:
Lee FL Dies used, FCD tried to no avail

 

[68wj]

I assume you don't have a case guage but the fast that they won't chamber is probably enough. Inspect your press/die setup and make sure something didn't come loose.

 

[MtnCreek]

Are all cases same manufacturer and once fired? Just wondering if some of the cases are springing back after being necked down. Also, I assume the seater die is not applying any crimp; correct?

 

[MEHavey]

Have you considered the effect of necking-down on neck wall thickness? Is there a possibility that you have a condition where the neck of the loaded case is now in a jam fit?

What is the current neck OD of a loaded case?

 

[noylj]

Measure and report.
1) cases too long
2) necks too thick
3) shoulder not pushed back on cases fired in different rifle

 

[bloominonion]

Case Neck OD: 0.285 (Up to 0.287 on the good cases.)
All cases were trimmed after sizing to 2.485".
No crimp from seater die. LEE FCD was used after it was found a round wouldn't chamber with a light crimp to smooth out the case neck dimensions.

 

[gamestalker]

Based on something I saw in one of my manual's, this is a common problem when necking down from 30-06 to 25-06. Because the mouth is so much larger on 30-06, the displaced brass builds up in the neck or shoulder when you put them through the die. I don't know if I termed that correctly, but basically the brass that accounts for the .308" bullet has to go some where when it is forced to your 25-06 .257" neck diameter, that thickens the brass on the neck or the shoulder. In general, a lot of neck and shoulder brass is being displaced during the necking down process. Some brass from the neck is being pushed into the shoulder, but the necking down is thickening the neck brass. This is probably causing those necks to be much thicker than what will fit, and then when you seat the bullet the neck expands which is when you'll notice the problem. I'll bet you had some pretty tight neck tension when you seated the bullets too, huh? I would be careful about shooting those rounds that do fit. There may not be enough space to allow for mouth expansion when you fire then, this could cause the mouth to get pinched when the bullet is exiting the mouth. Pressures could get quite high. You probably need to turn those necks down some.

 

[gamestalker]

Also, the trim to length is supposed to be 2.494". But I wouldn't be too concerned about that.

 

[bloominonion]

It seemed like the extra brass mainly went into length. I checked SAAMI Specs, and the case neck OD is supposed to be 0.290", so I am well under that. I ended up re-running the rounds through the FCD without adjusting it, but turning the round in it. I think it was leaving a non-concentric case mouth. After I did that, they seem to chamber just fine, and the dimensions are still the same at 0.285" neck OD.

The other rounds that were very far from chambering, I ran through the FL die again and they seemed to be fine (although, some brass just would not size down). Now they all chamber very easily (pinkie finger pressure).

So, would you think it would be OK to shoot these? SAAMI shows a chamber dimension of 0.291" (pre-crimp was something like 0.287" case neck O.D.).

 

[noylj]

Again, measure everything.
Case wall thickness?
Case neck ID?
Case length from datum on shoulder?
Really expect that your case wall thickness at the neck is too thick.
Would be nice to see some pictures of the "smoked" cases. I use Magic Marker.

 

[bloominonion]

Thickness: 0.015
ID: 0.256
OD: 0.285

All other cases, as far as I can actually measure match SAAMI specs.

It seems that either they just needed an extra run through the FL die, or a spin and re-crimp in the FCD. They all chamber now.

So would these be safe to shoot, or should I pull 'em?

 

[gamestalker]

If you are getting a consistent .015" thickness your probably OK. Also make sure you measure that OD after the bullet has been seated to be sure you are well within SAMMI on that. If everything is measuring to SAMMI, everything for sure, you'll be OK. A second run through the size die doesn't seem too unrealistic considering you had to reduce that neck down from a .308 application. Maybe you were a little hasty the first time around, maybe didn't use enough lube, weren't finishing the complete stroke, or the die wasn't camming over enough. At any rate, if the rounds are chmabering with normal resistence, and everything is measuring to SAMMI spec. I would personally shoot them. But from a personal stand point I would run a little longer OAL just to help prevent any more pressure than expected on the first run through. Just my opinion. I'm an OAL nut and always seat out as far as I can.

 

[JimKirk]

You stated that you smutted the cases and they had the same point of contact...

What was that point of contact? The base of the neck, where the neck & shoulder meet or on the shoulder farther down towards the case body?

I must ask this question also... do you have all the slack out of the press linkage(die adjusted correctly) ...no gap between the shellholder and the bottom of the die when fully raised with a brass in the die?

I have been sizing down 30/06 to 25/06 for 40 years ....never had a problem with doing it. My guns may have a looser cut chamber than yours.

Jimmy K

 

[bloominonion]

This is a brand new gun, never ever been fired, so that could be part of it.

The point of contact was across the top and bottom edges of the shoulder, along with a few points of contact in the middle area of the shoulder.

I checked that all slack was removed, and i even got it to the point of a stout cam-over for lack of a better word. I also measured with feeler guages to ensure no gap from die to shell holder. I am guessing the shoulder must not have been set back properly, along with a tight case neck dimension in the chamber. Since all have been set back, and the case neck OD has been made consistent via the FCD (all at 0.285") I would assume they are OK at this point.

Now I just have to find a stinkin place to go shooting....stupid snow in the mountains...

 

[JimKirk]

Sounds like you are getting good shoulder contact... your neck diameter is within specs ... was the smut scraped away all around the the neck ?

In my opinion ... your shoulder is not being moved back enough ... the only way to fix that is to remove some material off the top of the shell holder or off the bottom of the die.

In an earlier thread I cautioned NOT to use the Redding Competition shellholders because they add thickness to the shellholder which is opposite of what you would need. Your shell holder needs to be thinner... to allow the brass to go deeper into the die.

Jimmy K

 

[bloominonion]

It showed contact most the way around the shoulder. There was a spot or two of no contact.

So, should I file material off the die or the shell holder? Since the shell holder is used for other calibers, I would assume the die should be modified.

 

[TGReaper]

I ran into the same problem,and chose to remove material from the shell holder, in spite of the fact that I use the same holder for 3 other cartridges.
A couple of reasons 1) the shell holder is softer 2) and cheaper.
The actual amount of material to be removed is very small so the holder is still usable for the other cartridges.
TGR

 

[JimKirk]

I would try the shell holder first... much cheaper to replace one of them rather than a sizing die. Like TG said go slow and take off very little at the time.

Jimmy K

 

[kingmt]

I would put a filler gauge under the head of the case in the shell plate to get just a little bump. After the first firing in your rifle they may size easy & perfect the next time.

You might what to soften the shoulder a bit also this may take the sprig out of them. If part of them chambered then I would think the die is correct & wouldn't remove any from it. It sounds like ether adjustment or to hard of brass.

 

[Pacsd]

Blooming, I'm wondering if you have tried an headstamped 25-06 brass?