I started the thread “Why all the lube grooves.” To see what is known about the need for multiple lube grooves so perhaps they could be eliminated. The thread has morphed into an interesting discussion about breech seat and especially breech seating with gas checks in bolt actions. Individually breech seating the bullet is an appealing idea. The known drawbacks are complicated devices and loading time at the bench. Nothing wrong with the fuss and I kinda like doing it myself but it is slow and complicated. I will be interested in the outcome of this experimentation being discussed on the Why all the lube grooves thread. However I am even more interested in doing breech seating or a close enough approximation to breech seating to get the good out of the principle but with fixed ammunition which would eliminates a lot of the fuss. It seems to me that John Ardito essentially accomplished that years ago with a system of bullet design, swaging, and fit to throat that shoots as well as the best breech seaters. Others have done it with different bullet designs and swaging bullets into a die cut with the same reamer as the throat. My interest is to find a bullet design that will approximate the benefits of BS in a factory chamber and without the swaging step or the custom chamber. What I have been shooting in competition is pretty close but limited by non-custom match grade barrels and throats, factory triggers, and my shortcomings. That is why I was trying to determine if those extra grooves were of any use. Although there are theories about what they might do that is useful as far as I know none of it has been proven. I think the main reason for them is that they were needed for black powder and now may just be customary. The only way to find out is with a bullet designed without them and with good fit at the time when only a short length bullet is in the case. It may take stepped case mouths and other tricks but progress in this direction would benefit competitive shooters in production or hunting rifle class and any of the military classes as well as anyone else wanting better accuracy in a factory rifle. How close are we coming to breech seating with fixed ammunition? And what is the best way to proceed? John
How close can we come to breech seating with fixe ammo?
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joe --ok, i gotta work y learn ... the only breech seating i have done was on a stevens-pope, 32-40 ... used just an unsized case with a card wad ... don't remember black necks, even with mild loads of #80 . hey, maybe #80 is the answer !!
i do get black necks with even case seated bullets if the load is very mild ...
ken
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joe ...by blow-back do you mean blow-back that turns the case necks black ?
or blow forward that gas cuts the cast bullet ? i thought that is what breech seating does for us ::: seals the grooves ... ( and of course doesn't leave the bullet floundering in mid air trying to find it's way into the barrel . ) .
wouldn't the same bullet that seals when seated in the case also seal when breech seated even further in when pushed by a case neck ?
thanks kenI MEANT THE GAS THAT GOES AROUND THE CASE MOUTH AND MAKES THE NECK BLACK, SOMETIMES DENTED.? Caps lock comes on by itself, is someone out there doing that?
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joe ...by blow-back do you mean blow-back that turns the case necks black ?
or blow forward that gas cuts the cast bullet ? i thought that is what breech seating does for us ::: seals the grooves ... ( and of course doesn't leave the bullet floundering in mid air trying to find it's way into the barrel . ) .
wouldn't the same bullet that seals when seated in the case also seal when breech seated even further in when pushed by a case neck ?
thanks ken
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one reason that my so-far-fantasy ” 6mm super rook ” system works so good .. in my mind ...is that it is a heeled bullet, and can be pushed into it's tight throat by the case.
if you just drop the bullet into the chamber can't you just neck size a case down a bit and push the bullet in ? run a 30-06 neck into a 270 neck sizer die. i don't see a pressure problem with cast bullet loads. or put a brass rod into the 30-06 case and seat then put in the charged case.
or use a heeled bullet.
kenKen;I can't “just neck size a case down a bit and push the bullet in ? run a 30-06 neck into a 270 neck sizer die.” because of blow by. I bell the case mouth for every shot, that stops the blow by. The handle end of the Lyman #2 or pope re-de bells just enough. When I forget, if there's blow by, the result is visible on the target. Brass rod or wood dowel works fine for me with a plugged case.joe b.
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I'd like to add that I do nothing special to my cases. Neck size with a lee NS die only. No neck flare at all. Just seat the bullet after priming and adding powder. Just last evening I took 5 loaded rounds that I had loaded, measured the oal, then chambered each and remeasured them afterwards. None of my bullets were set back in the case after being chambered. All of the bullets showed marks from the lands. I guess I'm just lucky that my bullet fits so well. That said, I also shoot this bullet in 2 more rifles both 308 with factory chambers. One a Savage I rebarreled and the other a Howa 1500 with good results. Just my $.02
mrbill2
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I find this thread very interesting since my favorite rifle and the loads for it have a lot in common with what is discussed here. It shoots best with designs similar to John Alexander's NOE 22780, but in .30 cal(311331, 311334, long nose/short body). I seat them with just a little more than the GC in the case. The throat is similar to what frnkeore suggests above, but to the extreme. It has very little freebore(.05"), but the leade is cut .6” long on purpose by the arsenal to safely chamber and shoot .311” bullets in a .308” bore. The cases don't have enough meat to make a stepped case as joeb33050 described in this chamber(I considered it though); so I only size the top half of the neck and expand with an M die to create the step. I may test putting a cannelure in some necks instead of sizing and expanding to create the step, or alter a Lee collet die to put the band there. Loaded this way the bands seal against the throat while the nose engraves just enough length to guide it, but not so much it is hard to chamber with a slightly oversize nose and/or hard alloy. I have considered testing BS vs. this method since it would be relatively easy in this rifle.
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John,
Do you have only the GC in the neck of the case?
I didn't say it my post but, I always assume that the bands will fit the freebore with at least a size for size fit and the bore ride at a min of .001 interference fit.
Frank Frank, Seating depth depends on which bullet and which rifle. With the new NOE bullet just a tad more than the gas check is in the case in my Tikka. I agree with your definition of a good fit except for hard bullets when .001” interference fit may be hard to seat. John
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John, Do you have only the GC in the neck of the case? I didn't say it my post but, I always assume that the bands will fit the freebore with at least a size for size fit and the bore ride at a min of .001 interference fit.
Frank
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Throating is allowed in Production, so, what I would suggest is to pick a bullet and throat a rifles freebore until only the GC is in the case neck.
For the hunter class, it's a uphill road but, I would try having a bullet made that is a fairly tight bore rider (maybe put a lube groove in it) with driving band/bands that only occupy what freebore and leade that the factory chamber has and a long enough GC shank to get only the GC into the case mouth.
Food for thought,
Frank Frank, I believe that is good advice because that's what I've been doing since the early 1980s as I tried to say in my last post. The only difference is I haven't monkeyed with the throat and don't think that is necessary with the right bullet for the same reasons that you say you can use any throat if you seat the bullet ahead of the case. Take a look at NOE 22780sp. It comes pretty close to that in a SAAMI chamber. I have a bullet on order that I believe will come even closer.
I don't care whether we call it breech seating or something else. My original post starting the thread was to ask how close can we get to full breech seating with fixed ammunition. I think the discussion has shown that it is possible to get pretty close with the ways Joe lists and I think I am getting about as close with my approach which relies on neck tension. . I think with a benchrest quality chamber the effect of the case on accuracy would be nil but my interest is doing it in a practical factory hunting rifle and I don't expect to every shoot quite as well as the specialized, custom made benchrest guns which is OK. it's my windmill.
John
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The actual definition of Breech Seating is to install the bullet ahead of the case so, it can not be used in any class but, PB, Unp and Unr, I believe. And one thing that should be noted about actual BSing, is that when done that way, throating plays very little to no part in the accuracy of a firearm. We in Schuetzen use any type throat and get good to excellent accuracy. Any type, includes 15, 22 1/2, 30 and 45 deg in front of the case and also, includes freebores with long leades. One of, if not the main reason that we can get accuracy with those type throats, is because when using the steep throat, we use a tapered bullet to reduce the force when BSing. The first band is usually about 1/2 the groove depth.
It's fairly easy to get accuracy BSed but, it seems that the more the bullet has contact with the case, the harder it gets, without freebores and shallow leades to obtain accuracy.
Since 1985,I've helped many people get accuracy with their rifles when getting started shooting BSed. In that time, I've only had 3 that I couldn't get to shoot. A Ruger #1 in 30/30, original Stevens 25/20 (it only had .002 deep rifling and washed out throat) and a 32/20 on a 44 Stevens. Pretty good odds for accuracy with BSing, I would say.
Throating is allowed in Production, so, what I would suggest is to pick a bullet and throat a rifles freebore until only the GC is in the case neck.
For the hunter class, it's a uphill road but, I would try having a bullet made that is a fairly tight bore rider (maybe put a lube groove in it) with driving band/bands that only occupy what freebore and leade that the factory chamber has and a long enough GC shank to get only the GC into the case mouth.
Food for thought,
FrankThe actual definition of breech seating is whatever we agree it is. You ain't in charge of my language. The CBA requires the bullet to stay in the case when shooken for fixed, and a bullet in a step necked case can be shooken and not fall out. Arguing about term definitions don't help, the object is to leap the half inch hurdle. And, nobody = zero averages were below the hurdle in 2014. and, the SS guys ain't making much progress. Time to take a new path, maybe just a few steps. H. M. agrees, he told me so.
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The actual definition of Breech Seating is to install the bullet ahead of the case so, it can not be used in any class but, PB, Unp and Unr, I believe. And one thing that should be noted about actual BSing, is that when done that way, throating plays very little to no part in the accuracy of a firearm. We in Schuetzen use any type throat and get good to excellent accuracy. Any type, includes 15, 22 1/2, 30 and 45 deg in front of the case and also, includes freebores with long leades. One of, if not the main reason that we can get accuracy with those type throats, is because when using the steep throat, we use a tapered bullet to reduce the force when BSing. The first band is usually about 1/2 the groove depth.
It's fairly easy to get accuracy BSed but, it seems that the more the bullet has contact with the case, the harder it gets, without freebores and shallow leades to obtain accuracy.
Since 1985,I've helped many people get accuracy with their rifles when getting started shooting BSed. In that time, I've only had 3 that I couldn't get to shoot. A Ruger #1 in 30/30, original Stevens 25/20 (it only had .002 deep rifling and washed out throat) and a 32/20 on a 44 Stevens. Pretty good odds for accuracy with BSing, I would say.
Throating is allowed in Production, so, what I would suggest is to pick a bullet and throat a rifles freebore until only the GC is in the case neck.
For the hunter class, it's a uphill road but, I would try having a bullet made that is a fairly tight bore rider (maybe put a lube groove in it) with driving band/bands that only occupy what freebore and leade that the factory chamber has and a long enough GC shank to get only the GC into the case mouth.
Food for thought,
Frank
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Unless we define BS as requiring the WHOLE LENGTH of the bullet in the throat and rifling, before firing there is already a lot of BS going on in CBA competition. Breech seating is a matter of degree. The use of a bullet like 3xx299 or the RCBS SIL bullets has MOST of the bullet in contact with the throat and bore so with a less strict definition of BS they qualify.
I believe I BS with either my Mos bullet or the newer NOE 22780 (both designed for this approach). I try to get a fit by luck, sizing, lapping, or beagling so chambering the bullet in my factory chamber requires about all the force I can muster and results in most of the length of the bullet in the throat or bore and only the gas check in the case. I don't think I am the only one.
If we accept this less than strict definition of BS then we should add plain old neck tension to Joe's list of ways to achieve BS. If we don't accept this less strict definition of BS then BS can't be achieved by healed bullets, or stepped cases either because both fail to have the entire bullet in the throat and bore.
At least some of the current CBA shooters in Heavy, UNR, and UNP classes use a similar method, only usually with custom throating and swaging, to fire groups with fixed ammunition comparable to the best plain base (breech seating) shooters.
Maybe we need a definition of BS that defines how much of the bullet should be in contact with the throat and bore to be called BS. 85% anyone?
John
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one reason that my so-far-fantasy ” 6mm super rook ” system works so good .. in my mind ...is that it is a heeled bullet, and can be pushed into it's tight throat by the case.
if you just drop the bullet into the chamber can't you just neck size a case down a bit and push the bullet in ? run a 30-06 neck into a 270 neck sizer die. i don't see a pressure problem with cast bullet loads. or put a brass rod into the 30-06 case and seat then put in the charged case.
or use a heeled bullet.
kenSo the “how” to breech seat includes
Heeled bullet
case mouth push in
some kinds breech seater push in
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one reason that my so-far-fantasy ” 6mm super rook ” system works so good .. in my mind ...is that it is a heeled bullet, and can be pushed into it's tight throat by the case.
if you just drop the bullet into the chamber can't you just neck size a case down a bit and push the bullet in ? run a 30-06 neck into a 270 neck sizer die. i don't see a pressure problem with cast bullet loads. or put a brass rod into the 30-06 case and seat then put in the charged case.
or use a heeled bullet.
ken
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I have never tried breach seating, and am a total newbee to this , but could you put a canalure or ridge of brass on the inside of the neck and use that to seat a bullet into the rifling from the magazine. ( I wish I could provide a illustration here, but it is beyond my technical ability.) To do so you would need a rather long neck and a bullet and chamber that are “mated” together, or at least constructed to fairly close tolerances.
Many straight sided pistol cartridges cartridges have something similar could this be applied to a rifle round. Brodie
B.E.Brickey
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Bob Fitzgerald had a rifle and bullet where he dropped the bullet in, pushed the case in, the case seated the bullet and he fired the gun. I had a Schoyen Ballard and bullet in 38-55 that did the same, breech seated with the case mouth. Breech seating effort/business is about the dimensions of the chamber and bullet. It's easier to change bullet dimensions than chamber dimensions. Less permanent too-we can always sell or throw away the mold. If breech seating, eliminating the bullet leap from case mouth to chamber, is one of the ways to increase accuracy; then we need to think about how we can do that. I suspect that reduced accuracy is partly caused by bullets being pushed back into cases on chambering, varying effective case volume. A step-necked case eliminates this, and Mike Barrett has done work on cases that push the bullet into the chamber. My method, probably not original, works because Mark made the chamber neck .326". We can try making ex .308 from 30-06 or 30-30 from 38-55 to get more meat in the neck wall, but these meet with varied success-at least for me. I did have luck forming 300 Win Mag from 300 H&H. Some better scheme is needed, maybe putting .223 cases in .308 cases? The ideal is to have the bullet held in the case mouth so it can't be pushed back and does push into the chamber and make a seal, and sits in the case mouth so it comes out with no resistance, straight.
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Joe, that's incredibly cool. I've never heard of such a setup. I'd love to see those cases some day.
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In 1993 Mark Penrod finished putting the Douglas best barrel on a 12/15 Martini action and chambering it for 30-30 with a tight neck.This rifle uses step-necked cases, turned for a distance outside, fired with COW a few times and the step moves inside the neck. Annealing is involved. The bullet goes in and is stopped by the step. The bullet won't shake out of the case with reasonable shaking. Best bullets are 311299, 314299 and 31141. Among others, a Borton Darr PB and 308403 and 311291 don't shoot as well.31X299 and 31141 are lubed now with Lyman Super Moly and sized ~3095.The case making process, lengthy and fiddly, sets the inside neck step to push the bullet first band edge against the ball seat stop, for a seal. The case neck is AROUND the bullet, not behind it. This gun will shoot any of the 3 bullets into small groups all day long, with boring regularity.The range doesn't allow loading at the bench from a powder measure, so recently I've shot by breech seating the bullet with a plugged case-up to the stop-then putting in a charged case, 14.5/IMR4227 for example, and a plastic wad, the cases charged behind the line.So, it ain't breech seated as far in as the SS wizards, it's GC bullets sans GCs, and the case goes around the bullet base. But i<size=t shoots, and has since February of 1993.> 
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Today I had time to try a procedure for making fixed breach seating cartridges. I removed the seating stem from my junk box 30-06 seater and adjusted it to make a hard roll crimp on the 06 case mouth. I belled a case with my Lyman M die to take the whole gas check of the bullet into the case mouth. I set the bullet and case under the die and crimped the bullet to the case mouth. It worked like a champ and chambered in two different rifles with .312” throats. I used the Eagan US30 first because it is tapered from.298” to .312” It chambered fairly easily in the 03A3 and the model 70 target rifle. I next tried the Lyman 314291 and it was too big and got shoved into the case. Both of these bullets were cast of a moderately hard alloy a little softer than lyman no.2. I didn't load any with primers or powder. I just wanted to see if the process could work. They de-bulleted every time and I was able to measure bullets for size change and get a look at engraving. I didn't see much engraving on the fronts of the tapered bullet but got a nice scuff all around the back driving ring indicating a seal. The bullets were as cast with the hornady gas checks seated but not crimped. Crimping the case mouths also crimped the gas check.
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That's fine Frank, call it what you want.
LMG
Concealment is not cover.........
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