micrometer seating die

P

phil evans

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any major advantages using Redding micrometer seating die versus using the Forster micrometer seatng die for .308.
The Forster is ~$20 cheaper(Sinclair).
i have used the .243 micrometer Redding seating die for seven years.
components, etc., is where my stimulus is going

several years ago i bought and used the rcbs micrometer for .243 - did not like the useage.
i like every thing else about rcbs.

you all have gone far beyond my simple question -
my head hurts with your information that i cannot comprehend.
i'll get a redding..
whew!.
 
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I use both, but as I found to my surprise, the finer tolerances of the Redding mea that it may damage the bore of the seating plunger guide when seating long bullets on compressed loads. Seems that the nose of the plunger expands & scores the bore, though Redding replaced mine when it happened by return mail.

The Forster has a tad easier tolerances & hasn't done that - yet.

I'm happy with both & use the Redding for small slugs & the Forster for the 190-220s.
 
How does the RCBS Competition Seater stack up against the two?...
 
Guys, you might get better response on the Factory/Hybrid forum. Most users of this forum are 100/200 benchrest shooters and I'd guess that 98% use arbor press type straight line seaters like the Wilson.
 
JerrySharrett said:
Guys, you might get better response on the Factory/Hybrid forum. Most users of this forum are 100/200 benchrest shooters and I'd guess that 98% use arbor press type straight line seaters like the Wilson.
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I think more and more benchresters are using the Redding Competition seater. I know that I do and got a two station Hood press that has no arbor press. If my seater die's micrometer stem is graduated in .001's then I'm not very good at using my digital caliper. It's might hard to duplicate measurements with the Davidson ogive gizzie on a caliper because it doesn't take much to jam the bullet into it. I'm thinking I might cut a leade into the ogive half of the Davidson with my reamer. I'll give it some thought today, in fact.
 
MColeman said:
I It's might hard to duplicate measurements with the Davidson ogive gizzie on a caliper because it doesn't take much to jam the bullet into it. I'm thinking I might cut a leade into the ogive half of the Davidson with my reamer. I'll give it some thought today, in fact.
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Mickey, you might have an idea there. Cut a 1.5 degree bevel on the Davidson, that way it will duplicate the chamber leade. I have never had good success in duplicating the reading on a Davidson/StoneyPoint/Whitetail/LNL. You can always face it back off to a sharp edge.
 
I actually made such a tool using my chamber reamer about a month ago and it works very well. It gives you a much more positive and repeatable stop for the bullet. The tool also gives you a good relative measurement for establishing seating depth for different bullets.

FWIW,

Roy
 
Rcbs

DeSoto, the first thing you want from a seater is for it to produce a straight round (bullet on the same axis as the case). In my experience with three different RCBS competition seaters they failed that requirement. The RCBS design has a small sliding sleeve inside the die to support the case; unfortunately, it's really loose in there and it's very short as it is designed as a universal sleeve for a given bullet diameter. The loose fit of the sleeve in the die and of the case in the sleeve add up to poor concentricity of bullet to case in the loaded round. The Redding, Bonanza and perhaps others with a close fitting, single case sleeve do a significantly better job of producing concentric ammo.

German Salazar
 
DeSoto, a little more detail for you here:

Here you can see the small RCBS sleeve in the cutaway portion of the seater die. In a .30 caliber die, for instance, you can load anything from a .300 Savage to a .300 Weatherby with the same die. While that has economic benefits, it's not the best approach for real precision. (click the link for the picture).

highresimage



Here's the Redding, you can see that the internal sleeve supports the case fully and closely (of course limiting it to a single cartridge type). This is the better approach and is the one taken by most makers of this type of sliding chamber seater dies.

compseatingdie.jpg


German Salazar
 
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JerrySharrett said:
Guys, you might get better response on the Factory/Hybrid forum. Most users of this forum are 100/200 benchrest shooters and I'd guess that 98% use arbor press type straight line seaters like the Wilson.
Click to expand...

I know of several myself included that use The Forster seaters amd I size with a harrels die in my Coax press. I concur most br shooters use arbor press dies I do with my PPC's but its no wheres near 98% in my view.
 
Minor problem. The reamer won't go into the Davidson whatsis. I may sacrifice an old reamer and just cut off some so it will go in. It appears there is a slight bevel in the Davidson thing anyway. I tried to cut one but didn't have anything small enough so I got the other one and just polished it. Works better.
 
i have both redding and bonanza micro seaters for 308( one for 308 br, one for 308 win) and use a wilson inline for my 6ppc.
 
One variable that seems to be a function of the seater is the consistency of ogive to case head of a finished round. (BTW I always use a barrel stub with the front of the chamber in it to measure bump and differences in seating depth for my PPC.) Friends who went to the Redding micrometer seaters for their tight neck 6BR varmint rifles noticed more variation in this dimension than they would have liked. We guessed that it was due to variations in part stack compression and linkage flex or spring. Who knows? Nevertheless it was/is there. I would like to hear from those who are using these seaters for your PPCs as to whether you have surveyed your ammunition for this. As touchy as seating depth can be for tune, this is too important a characteristic to let slip under the radar.
 
MColeman said:
Minor problem. The reamer won't go into the Davidson whatsis. I may sacrifice an old reamer and just cut off some so it will go in. It appears there is a slight bevel in the Davidson thing anyway. I tried to cut one but didn't have anything small enough so I got the other one and just polished it. Works better.
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Mickey, just put the Davidson bushing in a 3-jaw and put the 1.5 degree bevel with the compound. Make it so it has a flat that is about 0.050" over the bore diameter to about 0.050" less than land diameter, or if you are adapting it to use on several calibers, make it under the smallest caliber and over the largest caliber by about 0.050".
 
JerrySharrett said:
Err, would you believe 96%??
Click to expand...

Ok. in that ballpark maybe. My point is what with the advent of the 30BR lending itself to pre loading and the RCBS Chargemaster being so good for dispensing powder I know a few people who are using custom seaters made from Forster or Reading 7/8-14 seater dies and have moved away from the arbor press.
 
Boyd Allen,

Further to your comments. I have also noticed that a Redding comp seater doesn't seat with as consistent a base to ogive as a Wilson seater. I found that even more true when high neck tension was used. Also the seated length will be longer at a high neck tension than at a low neck tension.

As best I can see the threads that do the seating depth adjustment are not precise enough and with some load on them they give somewhat. The Redding relies on that thread with no locking feature for the seating depth control while the Wilson has a bigger thread with a lock screw as the control.

I seated some rounds in a 6PPC-USA Redding seater and compared them with a Wilson seater performance. Granted the seater chamber wasn't as precise a fit as the custom chamber in the Wilson but the Redding seated rounds showed around 2 thou runout and a little seating depth variation while the Wilson seated rounds where consistent in length and showed around 1 thou runout. Granted the runout might be helped by a tighter seating chamber in the sleeve.

It has been my observation with Barts Ultra's (I assume the same applies to other double radius designs) that while seating depth is important it isn't like the accuracy will all of a sudden come together with just 2 - 3 thou changes. I tune with 5 thou increments and that seems to be more than sufficient to lock into the right depth. Interestingly a load around the 29 grain range liked Ultras at 10 thou longer than just touching while a 30 grain plus load likes the same bullets seated at 20 - 25 thou longer.

Bryce
 
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Bryce, I've considered, and experimented with, running the micrometer seater down until it's tight and using Skip Otto's shims to adjust my seating depth just as I would use them on a sizing die. The jury is still out but it seems to be working pretty well.
 
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