Thickside,

     Your bullet may be a nearly perfect fit requiring minimum seating pressure if it is matched to a specially cut throat in the barrel.  Otherwise, more seating force may be exerted with a plugged case or using a push seater if the bullet is close to the right taper for the throat.  If you really need some "OOMPH" on the bullet, you can use a mechanical seater, either utilizing a stud added to the side of the barrel or receiver Not a welcome addition to an original rifle) or one of the hook type seaters that are made by several of our craftsmen such as Jake Simmons.  The SSR Journal had a two part article on breech seating, the second of which came out in January and the first of which was a few issues earlier.  Modesty forbids me mentioning the name of the author,  8) but both issues are available to members at a reasonable cost from our archives...contact Rudi Prusok for details.

HTH, Froggie

PS  Our ASSRA treasurer has been known to drive his bullets in with a push seater and hammer, but it's OK, the hammer is marked "Pope."   

Thickside,

  Personally I breech seat a bullet that's .001" - .0015" lager than groove diam., But some will just size to groove diam. The feeling on the latter is that as the rifling engraves the bullet it will push out enuf to guarantee a positive gas seal.

  This gas seal is what you're looking for. I like the above .001" or so larger diam. as this will also fill the Leade....... that small taper just in front of the chamber...... that I feel will give a better and more positive seal.

  When you breech seat the bullet the idea is to push it in front of the case far enuf so that you can see the rifling on the front half of the bottom driving band.


  In any event, do not size your bullet less than groove diam. as there's a real possiblity of powder gas being able to bypass the bullet which you definitely don't want.

PETE

I'm planning a new bench rifle for breech seating and will obviously have to select a new mold and chamber combination. To make things easy for me to understand, assume a 30 caliber, .300" bore and .308" groove.
What should the bullet and "whatever you call from the end of the case mouth to full size lands" look like?
I'm guessing a tapered bullet. If the bullet tapers from .299" to .310" should the throat/leade/ball seat thingy be tapered the same? Is .299" to .310" right?
When I breech seat my guns now I'm frequently forcing a bullet in a not-very-tapered seat. However, I have and have had guns where I can drop the bullet in the chamber, push in a case over almost no resistance, and shoot small groups.
So with a clean sheet of paper, what's the best combo?
Thanks, and Hi Bob;
joe b.

Hi Joe, How are you?
Joe I cannot advise as to building a Bench gun. All my shooting and load devlopment is done offhand and so my criteria for a good load is somewhat suspect. if I call a shot a 25 and it comes up a 23 I am still satisfied. I do however often get those hail Mary shots where everything sits still and the rifle goes off and the follow thru feels real good. And when I look the bullet hole is smack dab on where I last saw the crosshairs on the target. When that happens I feel I have a good load and a good zero. Now all I have to do is string a bunch of those shots together. I will say that Pope seemed to have it figured out. I have two Pope molds, a 32-40 and a 38-55 both are tapered from under bore size to over groove size. The 32-40 actually measures .327/.3275 on the base band and .316 at the front band. Now this bullet has seated easily in every 32-40 I have tried it in and in rifles owned by others that I have given bullets to for trying. And most are factory chambers with no special throating. The 38-55 also fits everything but is slightly small and will shoot best when muzzle loaded using black powder. I have never tried my rifles on the Pope machine rest at the club as I do not want to be disenchanted. Every one who has done that has been unhappy with the results. An interesting  note. Jim Mc Dermott   from Ct. for many years shot Miller rifles with all the bells and whistles. But guess what he finally started shooting 250s with at 200 yds? A original Hiwall with a barrel 
rifled by Brezine. I do believe there are some benefits to different actions for different reasons but I have come to believe that good barrels are first, good casting second, good loading third, and good bench technique are more important than action. Not to say a Trapdoor will shoot with the best striker type action but within reason the Hiwalls, Ballards, Stevens by CPA can be made to shoot. Well enough for now. good luck on your project. Regards, FITZ.

Thickside,

     There are several breech seaters out there that sort of hook into the lip of the receiver that is exposed when the hammer and block are at their lowest position.  I bought one last Spring @ Etna Green from somebody, but for the life of me I can't be sure who it was.     I was thinking it was either Wayne Veitz or Jake Simmons, but I am really doubting my memory at this point.  I do remember that they seemed quite reasonably priced at the time, FWIW.  If anybody remembers who was selling them at the Memorial Day Match, I wish they would chime in and tell thickside and me both.

     The one I've got seems like it will work well, but is for the wrong caliber...I bought it knowing that I would have to make a new guide rod and plugged case to go on it.

     Can anybody help Mr. 'side and me?   ???

TIA, Froggie

PS  It seems that the .32-40 chamber and throat on the rebarreled Ruger #1 offhand rifle I have is the standard one, but with a Willis Gregory mechanical seater, it does well with some otherwise hard-to-seat bullets.  At last check, Willis didn't make Ballard seaters, but maybe he does now.  GF

Russ Weber makes breach seaters.

His contact information is:


18205 Hwy 141
Whitewater, Colorado
81527-9712

970-934-2863
russweber@juno.com

I'll contact Russ Weber.
In the mean time, is a gap of 0.125" too much between base of bullet and loaded case for breech seating.  Through tapping I can get the rifling approx 1/2 thru base band, and then when I use some cases on hand the gap is 0.125".  Is this too large a gap for safety?
Thanks
Thickside