Redding Micrometer Seating Stem on Lee or RCBS

[rcoody]

I'd sure like to know where in the Berger loading manual they state to seat 0.001 or 0.002 into the lands... I have it right here on the desk and I cannot find that.

You must jump a pill or you'll overpressure the case, but then, thats what the cross drilled holes are fot...lol

no not thousandths but hundredths

you have an old one

seems berger is more worried about pressure from deeply seated bullets than jams

Berger Tips for Loading VLD Bullets

The folks at Berger Bullets have just released an interesting technical bulletin that describes methods for optimizing bullet seating depths with Berger VLDs. The document explains how to find the OAL "sweet spot" for VLDs in your rifle. Interestingly, while VLDs commonly work best seated into the rifling .010″ or more, Berger's research indicates that, in some rifles, VLDs perform well jumped .040″ or more. This is a significant finding, one that's backed-up by real-world testing by many shooters.
The key point in Berger's report is that: "VLD bullets shoot best when loaded to a Cartridge Overall Length (COAL) that puts the bullet in a 'sweet spot'. This sweet spot is a band .030″ to .040″ wide and is located anywhere between jamming the bullets into the lands and .150″ jump off the lands."
CLICK HERE to download Berger VLD Tuning Tips
Writing in the report, Berger's Eric Stecker observes: "Many reloaders feel (and I tend to agree) that meaningful COAL adjustments are .002 to .005. Every once in a while I might adjust the COAL by .010 but this seems like I am moving the bullet the length of a football field. The only way a shooter will be able to benefit from this situation is to let go of this opinion that more than .010 change is too much (me included)."
For target competition shooters (for whom it is practical to seat into the lands), Berger recommends the following test to find your rifle's VLD sweet spot.
Load 24 rounds at the following COAL:
1. .010″ into (touching) the lands (jam) 6 rounds
2. .040″ off the lands (jump) 6 rounds
3. .080″ off the lands (jump) 6 rounds
4. .120″ off the lands (jump) 6 rounds
Berger predicts that: "One of these 4 COALs will outperform the other three by a considerable margin. Once you know which one of these 4 COAL shoots best then you can tweak the COAL +/- .002 or .005."
OBSERVATION and WARNING
Berger may definitely be on to something here, and we applaud Berger's testers for testing a very broad range of seating depths. However, we want to issue a STRONG WARNING to reloaders who may be inclined to try the 4-step method listed above.
Be aware that, as you load your cartridge progressively shorter, putting the bullet deeper into the case, you will be reducing the effective case capacity dramatically. With smaller cases, such as the .223 Rem and 6mmBR, moving from .010″ into the lands to .080″ and .120″ off the lands can CAUSE a dramatic pressure rise. So, a load .010″ into the lands that may be safe can be WAY OVERPRESSURE with the bullet seated .120″ off the lands (i.e. .130″ deeper in the case, the difference between .010″ in and .120″ out).
To illustrate, using a QuickLOAD simulation for the 6mmBR cartridge, moving the bullet 0.130″ deeper into the case can raise pressures dramatically. With the Berger 105 VLD seated .010″ in the lands (with 0.220 of bearing surface in the neck), and a charge of 30.0 grains of Varget, QuickLOAD predicts 60,887 psi. (This is using ADI 2208 data, and a 5500 psi start initiation value). If we move the bullet back 0.130″ further into the case, QuickLOAD predicts 64,420 psi (even after we drop start initiation pressure to the "default" non-jammed 3625 psi value). The 64,420 psi level is way higher!
Cartridge & LoadCOALJam/Jump*Start PressureMax Pressure6mmBR, 30.0 Varget
Berger 105 VLD2.354″+0.010″ in lands5500 psi60,887 psi6mmBR, 30.0 Varget
Berger 105 VLD2.324″-0.20″ JUMP3625 psi59,645 psi6mmBR, 30.0 Varget
Berger 105 VLD2.264″-0.80″ JUMP3625 psi62,413 psi6mmBR, 30.0 Varget
Berger 105 VLD2.224″-0.120″ JUMP3625 psi64,420 psi* As used here, this is the variance in OAL from a load length where the bullet ogive just touches the lands (first jacket to barrel contact). Loading bullets to an OAL beyond that point is "jamming" (seating bullet into lands), while loading to an OAL shorter than that is "jumping" (seating bullet away from lands).

NOTE: This is only a software simulation, and the real pressures you encounter may be different. But, the point is that moving the bullet 0.130″ further down in a 6mmBR case can raise pressures more than 3,000 psi! Therefore, you must employ EXTREME CAUTION when moving your bullets that much in a relatively small case. Remember that going from .010″ jam to a very long jump will probably increase pressures in your cartridge so you MUST adjust your load accordingly.
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[SidecarFlip]

I didn't have that but now I do....Thanks

 

[rcoody]

I didn't have that but now I do....Thanks

I was at work when I sent you that but I just checked my manual. It is on page 100 and 101 in my book. Berger goes into a little more detail in the manual.

 

[Trickymissfit]

out in the garage on the second shelf are three or four boxes of Bergers, plus a pair of Bergers that are flat based. The flat based ones shot best, but needed another inch or two of twist (contrary to what Berger refuted). When they did shoot, they shot well. Yet for every group they shot well, there were two more that didn't. I also saw problems with the bullets breaking up in coyotes, and even with reduced loads. Anyway, life is too short to have to jump thru a half dozen hoops to get them to shoot as well as the other brands.
gary

 

[rcoody]

out in the garage on the second shelf are three or four boxes of Bergers, plus a pair of Bergers that are flat based. The flat based ones shot best, but needed another inch or two of twist (contrary to what Berger refuted). When they did shoot, they shot well. Yet for every group they shot well, there were two more that didn't. I also saw problems with the bullets breaking up in coyotes, and even with reduced loads. Anyway, life is too short to have to jump thru a half dozen hoops to get them to shoot as well as the other brands.
gary

If you shoot the target VLD's and jam them 0.010 to 0.20 into the lands they will shoot bugholes. Far from mag length though. You have to single load them.

They changed the target VLD's to a thicker jacket. Many people were complaining about flyers. Berger found that the thin jacket was actually letting the lead core get hot enough to melt and the bullet lost all stability

The hunting vld is the old target vld with the thin jacket.

I was talking to a gunsmith the other day at the range. He is a long range shooter. He said he had a reamer made to fit the secant Olgive of the berger bullets and it shot really well. He said all rifles throats are designed to fit the Tangent olgive of all the other bullet manufacturers and that Is the real problem in getting bergers to shoot.

 

[ta406]

Got to be careful with no jump far as powder content is concerned. When the propellant first ignites, it pressurizes the case and with no jump, the pill cannot move freely so pressure increases way past what the case with wirhstand (if you load full house) Thats what jump is about, letting the pill move out of the neck and the initial pressure spike to recede.

Interestingly, with Berger 168 30 cal VLD hunters in my 2 308's 0.012 yield the best groups too.

I tend to caution newbies not to start with bergers and especially discount the chapters on case fill as it relates to jump (in the Berger reloading manual) If you are inexperienced.

Esperience has also taught me to only use bushing dies when trloading. I can dontrol the initial movement and integrity of a round in your pocket by altering the resistance the neck imparts to the pill.

I machine my own bushings btw. You can make a ton of bushings from a stick of drill rod.

Not to get off track but if you don't mind me asking, how to you machine the inside of the bushings? I'm a novice on a lathe and was always curious on what would work best. I have a small boring bar that might get down to .300 or so but any smaller than that I'm out of luck.

 

[Trickymissfit]

Not to get off track but if you don't mind me asking, how to you machine the inside of the bushings? I'm a novice on a lathe and was always curious on what would work best. I have a small boring bar that might get down to .300 or so but any smaller than that I'm out of luck.

normally done with a Sunnen hone with very fine stones. If you know what your doing, you can actually cut them on a lathe, but they also will be junk when your done. To make bushings, buy a piece of A2 drill rod, and turn the bushings leaving about five to eight thousandths in the I.D. Have them full hardened, and then hone them to size in a three step process. If your good, you can get by with three thousandths in the I.D.
gary

 

[barefooter56]

Hello

Does anyone know if the Redding micrometer seating stem fits on the Lee or RCBS dies. I know the Hornady Microjust only fits Hornady New Dimensions dies. Not so sure about the Redding.

Thanks
Sam

CleanShot,
As long as the threading is 1/2-20 where the seating stem assembly screws in on the die . You are ok.

 

[CleanShot]

CleanShot,
As long as the threading is 1/2-20 where the seating stem assembly screws in on the die . You are ok.

Yeah but how do I know that. I couldn't find it in the specs for either die.

 

[barefooter56]

Yeah but how do I know that. I couldn't find it in the specs for either die.

CleanShot,
Do you have or can you get a 1/2-20 tap?

 

[CleanShot]

CleanShot,
Do you have or can you get a 1/2-20 tap?

Sure. I can't imagine why I couldn't buy one. Are you suggesting I should tap the Lee/RCBS dies or just use the tap for just use it to determine the existing threading?

 

[rcoody]

Sure. I can't imagine why I couldn't buy one. Are you suggesting I should tap the Lee/RCBS dies or just use the tap for just use it to determine the existing threading?

It seems to me the whole reason for using the redding micrometer seating die is to load more accurate loads. I am not sure using the seating stems on dies they weren't made for much less modifying them is the proper path to follow.

 

[CleanShot]

Yeah I would agree but I'm assuming it's to check the existing threading.

 

[Garycrow]

Putting that micrometer seating head on a regular redding die doesn't turn it into their competition die, all it does is make it easier to make consistent seating depth adjustments. The redding competition dies, like the forster benchrest and ultra micrometer seating dies, have an internal sliding sleeve that is the key to their operation. it's what makes them better than standard seating dies. The micrometer head has nothing to do with how straight they'll load. I tend to use forster dies whenever they're available and any more I just skip the micrometer head. I just get the non-micrometer bullet seater, it works just as well and I've found any benefit from the micrometer head to be greatly exaggerated.

Here's a link to a redding page where it says the micrometer head can be put on a die with 1/2-20 threads. I assume they're talking about their own dies but it might work with other brands if they have that thread. It really wouldn't interest me though because it's still just a standard seater with a micrometer head, it doesn't give any of the advantages of the competition seater die or the Forster seating dies.

Micrometer Seat Stems for Standard Dies - Redding Reloading Equipment: reloading equipment for rifles, handguns, pistols, revolvers and SAECO bullet casting equipment