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Thread: If you think so, try this.

  1. #41
    Boolit Master Plinkster's Avatar
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    As far as microgroove rifling goes I have no experience but as a machinist I understand the theory behind it. Seems to me it's similar to the difference between coarse and fine pitch threads. Sure the coarse threads look big and burly and strong but what makes the fine pitch in fact stronger is the increased surface area that actually distributes the load. So microgrooves may in fact work better than ballad, with a projectile that fits properly for the malleability and hardness of said projectile. Now we all know that the manufacturers do not produce firearms for the masses to shoot cast, the masses shoot jackets. Back to the thread theory, a fine thread of X diameter will strip in aluminum before a coarse thread of same diameter does in steel. This is obviously due to material strength, yield pressures, etc. So this probably is why microgroove is looked down upon by casters as I suspect copper is just that much bit harder to be able to function in microgrooves. That and it's cheap to put in a barrel. Let me disclaim this by saying that I do not in fact own a microgroove gun and have not even inspected the bore of one, and that the above is all pure cranial conjecture based upon hundreds of hours of gleaning knowledge from mainly this site. I will add however that I have read a post or three claiming very good accuracy with cast in microgroove barrels.

  2. #42
    Moderator Emeritus/Boolit Master in Heavens Range
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    Quote Originally Posted by DIRT Farmer View Post
    Molly, OP would be origonal post.
    I am not sure my comment here is part of the consideration here as the loads I will comment on(recovered from snow banks which here are random enough in occurance to hamper establishing results) I have noticed with standard low speed rounds in the '06 using the Lyman 311-291 ( sized to .312) from air cooled WW a slightly wider grouve impression on the leading edge of the first driving band. With the wad cutters in 38 spl from a Smith 66 the widening is more pronouched. When I learned the grease grouves did not need to be in the case neck I no longer noticed the impressions being wider on the front. As I said I don't know if this adds to the discussion but there are two ends to the projectile.
    Hi Farmer,

    Yes, what you saw has been reported in the literature for at least the early 1900's. It's not the same thing that I saw.

    What you have encountered is usually referred to as 'skidding'. This is a term used to sum up a long-winded expression that would go something like this:

    "When the bullet is seated well back from the origin of the rifling, the powder charge has a chance to get it moving at a pretty good rate before it hits the rifling. By that time, the bullet has a pretty good forward inertia and no rotary inertia at all. The forward inertia keeps it going forward without rotation until the rifling has a chance to bite into the bullet and get it turning as well as going forward. This usually happens within the first body band, though it is sometimes seen on the second band too. Sliding on the angled rifling produces a V-shaped engraving here until the bullet begins to rotate. Once the bullet is spinning, the engraving on the bullet reverts to normal width for the rest of the body length. Revolvers are particularly subject to this because the bullet has to traverse the cylinder and the forcing cone before encountering the rifling.

    This usually does not present a problem in the practical use of the firearm, but if this skidding is believed to be a problem, it can be corrected by using a harder alloy or seating the bullet closer or actually into the origin of the rifling."

    What I was reporting may seem similar, but is actually quite different. I saw a very uniform engraving over the length of the body of each bullet, but which varied in width from duplicating the bore rifling in lighter loads to considerably wider than the bore rifling in more powerful loads.

    Hope this helps.
    Regards,

    Molly

    "The remedy for evil men is not the abrogation of the rights of law abiding citizens. The remedy for evil men is the gallows." Thomas Jefferson

  3. #43
    Moderator Emeritus/Boolit Master in Heavens Range
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    Quote Originally Posted by Plinkster View Post
    As far as microgroove rifling goes I have no experience but as a machinist I understand the theory behind it. Seems to me it's similar to the difference between coarse and fine pitch threads. Sure the coarse threads look big and burly and strong but what makes the fine pitch in fact stronger is the increased surface area that actually distributes the load. So microgrooves may in fact work better than ballad, with a projectile that fits properly for the malleability and hardness of said projectile. Now we all know that the manufacturers do not produce firearms for the masses to shoot cast, the masses shoot jackets. Back to the thread theory, a fine thread of X diameter will strip in aluminum before a coarse thread of same diameter does in steel. This is obviously due to material strength, yield pressures, etc. So this probably is why microgroove is looked down upon by casters as I suspect copper is just that much bit harder to be able to function in microgrooves. That and it's cheap to put in a barrel. Let me disclaim this by saying that I do not in fact own a microgroove gun and have not even inspected the bore of one, and that the above is all pure cranial conjecture based upon hundreds of hours of gleaning knowledge from mainly this site. I will add however that I have read a post or three claiming very good accuracy with cast in microgroove barrels.
    FWIW, my understanding of the theory behind microgroove rifling differs a little bit from yours, but neither explanation contradicts the other. It's my understanding that microgrooves were originated by a desire to reduce bullet deformation in the bore to an absolute minimum. And it's only common sense that a disruption that is ~ 0.0025" deep will produce more imbalance than a disruption that is only ~0.001" inches deep. The theoretical advantge thus lies with the finer rifling. However, it's noteworthy that I know of not a single competition shooter who uses barrels so bored.

    That does not mean that the microgroove system is without merit: I understand that it works fine with jacketed or paper patched bullets, though it has been reported to wear out a lot faster than normal rifling. I have also read an occasional report of good results with regular lead bullets, but they never seem to provide enough real information like alloy, hardness, load and velocity to enable a real understanding whether something unusual is really going on.
    Regards,

    Molly

    "The remedy for evil men is not the abrogation of the rights of law abiding citizens. The remedy for evil men is the gallows." Thomas Jefferson

  4. #44
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    The comments on "stripping the rifling" interested me greatly. I've seen the term hoo hahed by some very knowledgeable people..."it just doesn't happen" etc.

    They've obviously never worked with a Japanese Arisaka before. At higher velocities I HAVE to use a very hard alloy or my groups look more like shotgun patterns. Those Metford rifling lands are great for preventing the accumulation of fouling, but being rounded they need a hard boolit!

  5. #45
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    Quote Originally Posted by BABore View Post
    One thing I would be looking hard at is the use of linotype. Sure, it's plenty hard enough at around 22 bhn. It's also extremely brittle without any give, toughness, and elasticity. The increased pressure on the leading edge of the rifling permanetly shifts the material through shearing forces. Shear forces aren't kind to hard, brittle materials. HTWW's would work slightly better, but can still suffer from the same fate if your WW's happen to HT into the 28-30 bhn range. Water dropping WW's will show a slight improvement since it's more apt to produce a slightly softer core if done right. It's also much harder to do on 30 caliber boolits than bigger diameters. Although this doesn't necessarily apply to the OP topic of rifling marks widening and gas blow-by, both lino and WW's have another fault at HV. High antimony levels. At HV you tend to pick up more grey wash in your bbl which is caused by the antimony that has migrated to the boolits exterior. That wash is a hard fouling that reeks havoc on boolits.

    A much better alloy choice would be a mix of 50-50 to 60-40 WW's and Pb, water dropped. Shoot for final hardness of 22 bhn and age the boolits at least a month. The same hardness as lino, but it will have the toughness and elasticity that will tolerate the high torque and shear forces. You also reap the benefits of the lower antimony level and reduced fouling. If even more toughness is needed, add a small portion of nickel babbit to the 50/50 alloy. The small amounts of nickel and copper will increase both hardness and toughness.

    The next step would be proper boolit fit. The OP said that the boolit was seated to touch the rifling. That's all good. What about the rest of the boolit. Is the throat filled with boolit? Is the boolit sized big enough so the expanded case doesn't leave the boolit base hanging in the breeze? That wasn't given. The boolit has to get into the bbl straight and with the least amount of damage to give it a fair chance.

    Finally, how you launch the boolit has a big impact on how it takes the rifling. High launch pressure will cause more distorsion and skidding. Getting the boolit into the bbl before it gets hammered is most desirable. The OP's use of 4831 in the 30'06 is a good start. You need a slow for caliber powder to pull it off. But, was it the right powder? Maybe. There's a whole slug of powders in the same burn rate and slower that could also be the one. You just have to try them. It's also sometimes necessary to make use of a compressible plastic buffer to further cushion the boolit base from the high pressure. Lube will also play into this to keep fouling down. Some work better than others.
    If there was one response I have ever read here that is worth its writers weight in gold, this one is it. I hope the newbies are paying attention.
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  6. #46
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    Quote Originally Posted by waksupi View Post
    More mis-information abounding. Companies like Century Arms import various firearms for refurbishing, and use a roll stamp according to federal law, to mark them. So just because something is marked CAI, doesn't mean they can't be a somewhat legitimate piece. I know I worked on around 6000 AK's from Romania, that were wearing that stamp.
    He was trying to sell it as a "bring back" that is a weapon etc that was brought back by a soldier after WW 2 around 1945, they have no import markings because the 1968 GCA did not exist.

  7. #47
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    Thanks Molly, For many years I have been in a "casting wilderness" where my info came from the Lyman book and the rare article in The Rifleman. I descovered the advantage of filling the throat when using a rifle reguired .312 to be the standard .001 over bore. Back to your point, I have recovered castings that have had the land impression that were wider than the groove impression. Basicly I had no clue why but knew they leaded and strayed from the target.
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  8. #48
    Boolit Master mroliver77's Avatar
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    I am surprised nobody else has chimed in about micro groove rifling. I have three Marlins with MG. They shoot cast very well. They are a bit more finicky about loads but with proper loading they perform as well as any other factory gun I have.

    One thing that needs to be understood is the BORE is larger due to the shallow rifling. Bore riders suffer if the nose does not fit well. Another thing is Marlin 30-30 does not have a throat per se. It is more like a funnel from the neck o.d. to the bore size. Hard boolits handle this setup much better than soft does. My best shooting boolit in my Marlin 30-30 is an LBT 150gr . It is sized .310 and cast out of WW +tin or WW/PB 50/50 with 1-2% tin and quenched. Boolit lightly engraves when chambered. I use H414 powder for this load as it is on the slow end of suitable powders and is easier on the boolit. Looks like BABore and I subscribe to the same theory!


    I fire soft lead also but with light loads. Again well fitted boolits are a must. I have a 311440 with a larger nose that shoots well in this gun. Even out of pure lead over 3 gr Bulls Eye shoots well. .313 round balls over small doses of BE is a bird bashers dream. I roll them in alox. I want to try 45-45-10 mix on them someday.

    I could go on with the other MG guns but the loading regime is the same and the outcome is also. MG barrels do shoot very well. I don't know if they shoot benchrest well or not. Now you got me thinking!

    I forgot to add that I have NEVER had the slightest trace of leading in any of my MG barrels!

    Jay
    "The .30-06 is never a mistake." Townsend Whelen

    "THESE are the times that try men's souls. The summer soldier and the sunshine patriot will, in this crisis, shrink from the service of their country; but he that stands by it now, deserves the love and thanks of man and woman. Tyranny, like hell, is not easily conquered; yet we have this consolation with us, that the harder the conflict, the more glorious the triumph."
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  9. #49
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    Hey there fellers, I wanted to show the inspiring results that I have gotten by following what I learned on this thread.
    First, I took pictures of what happens with the original groove size boolits (.358) in my .358 Malcolm wildcat. (In all of these results that I am going to show, the boolits were going faster than 2150fps with H335 powder.)


    As you can see the boolits left a lot of lead in the barrel. The patch has gobs of it all over. That was one shot from a gaschecked boolit with two coats of 45/45/10 lube. (dont laugh I used that light lube because I wanted to test what I learned on this thread.)
    The next boolit that I tried was identical to the first except that it was sized to .360 instead of .358.

    As you can see, the difference is astonishing. Im sure you all are familiar with 45/45/10, and you know that there aint much lube there. I proceeded to shoot another five shots of the .360 diameter boolits and when I pushed the patch through, I got a few speckles of lead on the patch.
    Next I tried felix lube (the best I could do anyway) on the same .360 diameter boolit and it yielded about the same result as the 45/45/10 did with one shot. So I loaded up 10 of them and shot them all with out cleaning the barrel. When I pushed the patch through, I was amazed.

    There was no lead speckles at all. Nothing. Just powder residue. I think that this proves conclusively that what the OP was claiming is true (at least its gospel for me now) Although I knew I was reading truth when I read the OP. I have shot so many boolits the wrong way, I can tell you that I have experienced all most all of those scenarios he listed as experiments, I just didn't know what I was looking at.
    Since I have taken those pictures I have continued to drive boolits very fast, and I have gotten some very good results from them.
    Here's a 50yrd group with 200gr RCBS GC boolits I was pushing them 2250fps!

    Thanks for setting me strait Molly! I got more out of this thread than any other one thread on CastBoolits. It was definitely a light-bulb moment, reading the OP.
    Last edited by goodsteel; 06-22-2011 at 06:59 AM.
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  10. #50
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    Hi again Goodsteel,

    >Thanks for setting me strait Molly! I got more out of this thread than any other one thread on CastBoolits. It was definitely a light-bulb moment, reading the OP.

    I really DO take some pride in what I've learned about cast bullets ... until I reflect on how ignorant I was when I started. I don't think there's a single idiotic mistake or notion in the field that I haven't tripped over. You can rest assured that any understanding I have is only the residue left over after making just about every possible mistake in the book, and custom developing a few new ones just for the sake of completeness.

    My very first cast bullet load consisted of a long nosed spitzer bullet cast from the cores of recovered jacketed bullets - the lead had to be a good alloy because it shot so well in jacketed loads, right? It was sized to exact bore diameter and lubed - IIRC - with either Crisco or lard. Cooking grease of some sort anyhow. And it was loaded in a 30-06 over a max load for a jacketed bullet of the same weight. Accuracy was something on the order of 30 or 40 degrees of angle. Not minutes of angle. DEGREES! And the leading was so massive that there remained not one visible trace of rifling in the bore. That - like so many of my loads - constituted a real learning experience.

    And every time I recall that experience, I am reminded of Ben Franklin's commment that "Experience is an expensive school, but fools will learn in no other way."
    Regards,

    Molly

    "The remedy for evil men is not the abrogation of the rights of law abiding citizens. The remedy for evil men is the gallows." Thomas Jefferson

  11. #51
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    I'm glad I came across this thread. It's great when the guru's "forge." Us newbies in nappies often learn a lot in the process. Welcome goodsteel!


    One thought though:

    Leading occurs when the hot gas swirls past the lead bullet and etches off tiny traces of lead alloy. This is slammed against the film of lube in the bore, which keeps it from sticking for a while. But as the load is increased, there is more force trying to make the melted lead touch the bore, where it sticks and builds up in the adherent mess called leading.
    While probably a "good enough" description, I would postulate a more accurate description is when the hot gas flows past the lead, the lead sublimates. (The vaporous lead then condenses* a moment later).

    *sublimates, technically. The term "sublimate" is used for both directions (solid to gas, gas to solid), though I've also seen the word "deposition" used in an "applied" meteorology context to describe gas to solid.

  12. #52
    Moderator Emeritus/Boolit Master in Heavens Range
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    Quote Originally Posted by Dannix View Post
    While probably a "good enough" description, I would postulate a more accurate description is when the hot gas flows past the lead, the lead sublimates. (The vaporous lead then condenses* a moment later).
    Well, my (VERY) limited experience suggests that etching of tiny molten droplets is the most likely mechanism. I don't know a whole lot about sublimation, as the ONLY experience I've had with it was ice sublimating off my steps in the dead of winter. But in that case, the surface residues were high in gloss (shiny).

    On the other hand, the surface of the gas check shank turns very dull when leading occurs. It goes from a shiny cast surface to one that looks as if it had been acid etched, which is why I used the etch terminology as opposed to sublimation terminology.

    This etching is one of the areas that still mystify me. One would expect that the gas leakage (and subsequent etching) would be least where the fit of the bullet to the bore is tightest. But that's not what I find: The etching is first evident in the very tightest spot, where the gas check is engraved by the rifling. From there, it gradually increases with hotter loads until it encircles the entire top of the gas check band. This does not seem logical or reasonable to me, and suggests that - let's put it politely - my explanation (and/or my understanding) may not be complete. I'd invite comments on the subject.
    Last edited by Molly; 07-07-2011 at 09:01 PM.
    Regards,

    Molly

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  13. #53
    Boolit Master nanuk's Avatar
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    etching, sublimation...

    just makes me wonder, if the hot gases etch the boolit, AND the GC, then they also must etch a j-word.

    also, on high round/minute or high pressure/heat rounds, throat erosion is probably etching in the same context. Gas Cutting?

    as to why it goes past the GC and around the perimeter before it cuts the next band, that could be as simple as the gas going to an area of least resistance....

    or I may be completely misunderstanding

  14. #54
    Moderator Emeritus/Boolit Master in Heavens Range
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    Quote Originally Posted by nanuk View Post
    etching, sublimation...

    just makes me wonder, if the hot gases etch the boolit, AND the GC, then they also must etch a j-word.

    also, on high round/minute or high pressure/heat rounds, throat erosion is probably etching in the same context. Gas Cutting?
    Yes, I have no doubt that the copper jacket of a modern bullet is etched. BUT ... for one thing, it's probably pretty hard to tell, as the high velocities result in bullets that are more or less shredded. And for another, the level of etching is probably quite low, as the melt point of copper jackets is FAR higher than the MP of lead alloys, and this would sharply limit the amount of etching that occurs.

    The same would hold true for the barrel steel that is involved in throat erosion. Any etching that may occur is almost certantly negligible. Throat erosion is caused by an entirely different mechanism. When a high power round is fired, the temperature of the burning nitrocelulose gas is well above the melting point of steel. Only the brevity of the exposure keeps the barrel from melting. It's sorta like flashing your hand through the flames on a gas stove. If you do it fast enough, you'll hardly feel the heat.

    But though the barrel itself doesn't melt to any appreciable extent, a VERY shallow surface layer actually does melt, and is instantly cooled back down by loss of heat to the rest of the barrel. The damage is caused by the fact that barrel steels contain an appreciable amount of carbon. The rapid cooling results in in a quench hardened steel layer just as if you had cooled a bit of cherry red steel in a tub of water. Thin though it may be, it no longer has the flexibility it did before. It's brittle. And when the next round is fired, it cracks. As more and more rounds are fired, the cracks get larger and deeper, until the passing of a bullet begins to chip tiny flakes of the brittle steel off of the bore.

    This process has been exhaustively researched and documented by the military, who has a deep and abiding interest in the longevity of their weaponry. There is absolutely no doubt about it. And the reason that the erosion is pretty well limited to the throat is because the gas cools as it expands down the barrel. The further down the barrel it is, the cooler it is, and the less effect it has, until the flame temperature is below the melting point of the steel, where the effect completely dies out.

    Hope this helps.
    Regards,

    Molly

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  15. #55
    Boolit Master nanuk's Avatar
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    Molly: I understand how you explained that

    thanks for that

  16. #56
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    Quote Originally Posted by nanuk View Post
    Molly: I understand how you explained that

    thanks for that
    You're welcome nanuk. It's no great revelation though: The better books on firearm technology have detailed it since at least as far back as WWII - or was it WWI?

    One of them (I THINK it was in 'Hatcher's Notebook') went into it in considerable detail, with illustrations of the erosion in artillery barrels after so many rounds, after so many more, and after more yet. It's quite informative, and well worth the trouble of digging a copy up somewhere. I particularly enjoyed a story of the guy who convinced someone high in raqnk, but low in firearms knowlwede that hardening the barrel would reduce wear and extend barrel life. The order came down to explore the notion.

    The ordinance boys came up with a moveable setup that could be pushed rapidly up the bore to heat the surface and followed it up with a column of water right behind to quench it, giving them a much harder bore surface than usual. When put to the test of actual shooting, lengths of complete lands were broken off because of the expansion of the barrel (from gas pressure) and the inability of the hardened bore surface to flex.

    A lot of people still don't realize that just as gas pressure will expand a rubber balloon, it will expand a steel tube (IE barrel) too. Granted, a barrel doesn't expand a whole lot, and it takes a lot fo pressure to do it. But don't ever doubt that it expands. In point of fact, it does considerably more than expand. It also whips back and forth, and up, down and sideways, much like a garden hose gripped too far back from the nozzle - and for exactly the same reason as the garden hose does it. But it's usually referred to as 'barrel vibration' by the writers.
    Regards,

    Molly

    "The remedy for evil men is not the abrogation of the rights of law abiding citizens. The remedy for evil men is the gallows." Thomas Jefferson

  17. #57
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    I just reread this thread again. Its been over a year and there is a lot of water under my personal bridge. I still got more out of this thread than any other.
    Thanks again Molly, I'm still thinking about your original post at least once a week.
    Good info here, and I'm glad I listened.
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  18. #58
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    Just a guess, but maybe the gas speed is higher as it escapes through a smaller gap causing more gas cutting at the smaller gaps.

  19. #59
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    I have been handloading for 60+ years and thought I really knew what I was doing. Then I joined Cast Boolits and learned that I didnt know squat! Have learned more here in the past couple of yrs. than in all of the previous 60 yrs.

    Larry

  20. #60
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    Major Roberts (and Haarry Pope) suggest you try this...

    Well, I realize this thread is an oldy but a goody, but having just read it for the first time, the initial discussion and the OP's focus on the effect of engraving on the bullet, disproportionate impact on the lower edge of the bullet and cutting by the lands triggered a memory of having read something relative to this.

    Sure enough, Major Ned Roberts of Schuetzen shooting fame, writing in Hunting and Fishing July 1943 addressed this very issue in describing the advantages of muzzle to breech seating bullets in the Pope rifles as opposed to straight breech seating. For those unfamiliar with the practice, in single shot Schuetzen (200 yard offhand) shooting, it was the norm with Maynard, Ballard and other rifles prior to the Pope rifles to seat the bullet (cast) into the lands at the breech, to use a single case which was decapped, primed, and charged between each shot and a card wad placed over the charge, at which point the case was placed in the chamber such that the bullet base was optimally 1/16th" or less from the case mouth, but not actually enveloped by the case mouth. This obviously exposed the bullet base and shank to combustion and supports the view of many that the bullet filling the THROAT rather than just the bore is important to accuracy and bullet stability. Along came Harry Pope and with his rifles he supplied an indexed muzzle extension (false muzzle cut from the original barrel and indexed to the rifling) and a bullet starter, so that the bullet would be inserted into the muzzle and pushed down the barrel to seat in the breech, after which the charged case was placed in the chamber behind it. The false muzzle was removed and the shot taken. Needless to say barrel overheating was not an issue. Pope's rifles were notably more accurate and took the Schuetzen world by storm.

    Major Roberts explained why this was so, in his opinion (relevant to the thread above):

    A bullet loaded from the muzzle will shoot more accurately than a breech seated one because in loading the muzzle loaded bullet the lands cutting forward into the bullet leave the base perfect without any burrs behind it . Contrast this with the bullet seated in the breech; here the lands cutting backwards into the bullet drag out burrs behind it, leaving an uneven serrated base. If this bullet is not perfectly centered these burrs will be longer on one side than on the other . As these burrs leave the muzzle, the gas escapes first first from the short side, tipping the bullet to the opposite side, in which it is assisted by the longer burrs holding the bullet back; the result is an uneven, wobbling flight. The greatest essential to perfect shooting is to deliver the bullet perfectly from the muzzle; that being done, atmospheric conditions and gravity alone govern the flight and results in accurate shooting. To so deliver the bullet, it must have a perfect base, be perfectly centered and have uniform velocity. (Bold in the original article, underline added)

    I can't say as I follow how muzzle loading the bullet to the breech will leave the base perfect inasmuch as it has been engraved on the way down the rifling and the lands will have cut and serrated the base, albeit with any "burrs" arising there from heading up towards the muzzle rather than back towards breech and combustion. I imagine his case was that the cuts were smaller, would seal better with obturation and allow little to no combustion gas to pass the bullet in its journey down the barrel. He makes no mention of gas checks in the cast bullets universally used though does reference paper patching, albeit not as universal practice.

    His remarks do however speak directly to the points that Molly was trying to articulate and, in my understanding at least, bridge the distance to the points that 45.2 and other "old hands" were making. In any event, it has most certainly peaked my interest in having a go at breech seating some paper patched (to fill out the leade) .454 bullets in my H&R single shot 45 Colt/454 Casull (below) and to keep an eye out for a 38-55 or 32-40 Schuetzen that I can afford.

    Roberts makes for very interesting reading and reaches back to an age when casting and shooting cast bullets were the norm.

    Not exactly a Schuetzen but definitely a Stutzen:


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Abbreviations used in Reloading

BP Bronze Point IMR Improved Military Rifle PTD Pointed
BR Bench Rest M Magnum RN Round Nose
BT Boat Tail PL Power-Lokt SP Soft Point
C Compressed Charge PR Primer SPCL Soft Point "Core-Lokt"
HP Hollow Point PSPCL Pointed Soft Point "Core Lokt" C.O.L. Cartridge Overall Length
PSP Pointed Soft Point Spz Spitzer Point SBT Spitzer Boat Tail
LRN Lead Round Nose LWC Lead Wad Cutter LSWC Lead Semi Wad Cutter
GC Gas Check